Endondonticsdd2011-2012 dr ghadeer

lDstrumerts/Materials/Techniques

ENDODONTICS Access Preparations,

Imagine the access preparation for a maxillary c€ntral incisor.

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Copyrigh e l0ll-2011- Dental Decks

IIarillary Central IncisorAccess Opening

Maxillary Lateral IncisorAccess Opening

Maxillary CanineAccess Opening

Reprinted liom liglc. J l, dd B ak1^nd LK. Endodontics Fourth E.litian O I 99i1. s irh pennission from Williams & Wilkins.

2Cop:/right O ml l-412 - Dcd.l D.ct8

3Cogyrigh O 201 l-2012 - D.dl Drck

Mandibular CentralIncisor

Access Opening

Nlandibular LateralIncisor

Access Opening

Nlandibular CanineAccess Opening

Reprirted arorn lngle. JI. a.d Bakllnd LKEnd.,lanti.s Fat h E.lition .t l1)t)1, *\thlennisron ftinn \\rllams & Wilkins

Maxillary First PremolarAccess Opening Maxillary Second Premolar

Access Opening

Rctrin!.d tion fngle. Jt- ind B^ll^..1l,K E,l.)tldnns. FottthO 199.1, wilh lremission tionr $illiam\ & $llklns

One canal

Onc canalOne fbnmen

One canalOne foramen 15%

Two canalsTwo lbramens 21o

Three ca.als 1Yo

4Cop)'right O 20 I I -20 l2 - Denhl Decks

Cop).righr O 201l-2012 - Dental Decks

R.pn n'ed riofr lngle. Jl. and Btkland LK. Lrtlodontu s. Fourli td,rt,, q I 994. wnh pemission from u illiams & willins

Mandibular First PremolarAccess Opening

Maxillary First MolarAccess Opening

Mandibular Second PremolarAccess Opening

Maxillary Second MolarAccess Opening

One canalOne foramen

Two canals

One foramenTwo canals

'I wo foramens

One canalOne fommen

Two canalsOne foramen

Two canals

MB 19.9 mmDB 19.4 rnmPalatal 20.6 mm

MB 20.2 mnDB I9.4 mmPalatal- 20.8 mm

Three 54%Fused 46%

Reprinred frcrn Ingle, Jl. and aakl^ndLK. Etulo.lontns. r'auth Etlition A 1994. vith penission rion willians & willins

Coprighr O 201 l-2012 - Dental Decks

. A persistent periodontal defect

. A radiolucent halo surrounding the root ofthe fracture

. A radiopaque lesion at the sight ofthe fracture

. A visible fracture when transillumination is used

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Coplrigh O 201 l-2012 - Dental Decks

Mesial 20.9 mmDistal 20.9 mm

Two canalsThree canalsFour canals

]lesialTwo canals

One foramen 4l%Two canals

T\r'o foramens 59olo

DistalOne canal 72%Two canals 28%Two canals

One fommen 62%Two canals

Two foramens 38olo

Mandibular First MolarAccess Opening

Mandibular Second MolarAccess Opening

Repnnred |Ion fngle.Jf.and B nkt^nC,I K. End.danti.s Fnurthfdt!,, g 199.1, silh pe.misstu. fion Willilns & Nilklns

Often times transillumination is used to see the defect, but ofcourse, this cannot be diag-nostic on tooth structure that is under bone. Also, persistent periodontal defects are oftencaused by vertical root fractures; however, this is not radiographic (read the questioncarefu I I1') .

Important: Radiographs lwltlrout.lirst wedging the lootiT rarely will show veftical frac-tures.

Vertical fractures will often be recognized radiographically by their effect on the bonyattacirment apparatus that is seen as a diffhse radiolucency or "halo" surrounding theroot. This can be differentiated from other periapical radiolucencies because it surroundsthe tooth uniformly ratherthan being located at the portal ofexit ofthe apical foramen orlateral canal.

l. A tooth with a vertical fracture through root structure has a poor progno-\otes sis.

';q:.:,.r', 2. Studies have indicated that most vertical root fractures are caused by toomuch condensation force during obturation with gutta-percha.

Therapy for horizontal fractures of the root always involves considerable difficulty.Root canal treatment is not indicated if the fracture sites remain in close proximity and

ifthe pulp retains its vitality. However, ilclinical symptoms develop or the segments ap-pear to be separating according to the x-ray, some treatment is necessary.

Remember: Root fracture can only be visualized on a radiograph if the x-ray beam passes

through the fracture line. As the fracture line could extend diagonally, an additional radi-ograph is taken with a 45" (steep) vertical angulation in addition to the conventional 90".

Mesial 20.9 mmDistal 20.8 mm

Ong canalOne fommen l3Yo 92%

Two canalsOne foramen 49vo 590

Two canalsTwo foramens 38% l',,

. #19 - virgin

. #15 - primary cavitation on occlusal

. #3 - fulI gold crown

. #30 - occlusal amalgam

8Copyrigbr O 201l-2012 - Dental D€cks

coplrighr O 201l-2012 - Denral Decks

. Same

. Opposite

EPT checks the sensibility of a tooth by stimulating ncrvc cndings with a low current and highpotential difference in voltage. Although manufacturers ofthis device give normal relerence val-ucs ofcurrent, the best way to check "nolmal,/baseline" values is to use it on adjacant t"ron-patho-iogicai) teeth. This is then compared with the values obtained on the looth being questioned. TheEPT uses electrical excitation to stimulate the A-delta sensory fibers in the pulp. A positive re-sponse does not provide any information about the health or intcgrity of the pulp: it simply indi-cates that therc are yital sensory fibers present. lmportant: The EPT fails to provide anyinformalion about the vascular supply to the pulp, which is the truc determinant ofpulp vitality.

Note: EPT is not considered reliable in the following conditions.

1. A pus-fillcd canal -

t'alse positivc

2. A nervous patient -

false positive

.1. Recent dental trauma -

lalse negatire4. hsulating rcstoration

- false negative

5. Sccondary dentin deposits -

falsc negative

6. Moisturc (ontaminalion -

[alsc positir c

7. lmmature tooth t'open apex) -

false negative

8. Patient who has taken analgesics -

false negative

lmportant: Never wear gloves while using the EPT as this impcdes conrpletion and results in a

false-negative response. Also, ifa paticnt's medical history reveals that a cardiac pacemaker has

been implanted, the use ofan electric pulp tester is contraindicated.

Response to EPT:. Acute pulpitis: lower than normal current, as acute inflammation mediators lowcr the painthrcshold. Hlperemia: lower than normal, but higher than that seen in acute pulpitis. Pulp necrosis/abscess: no response at any currenGlevel

ln other words, wc can say that the cone image shift technique separates and idenlifies thc facialand lingual structures. Noter The cone shif-t technique is also known as thc buccal object rule,SLOB rufe (Saae Lhgual, Opposite Buccaf, Clark's rule or Walton's Projection.

As the conc position moves lrom parallel either towards horizonlal or vertical, the objcct on the filmshifts away from the dircction ofthc cone (i.e., in the direction ol the central beatt).

Note: ln order to apply this rule, you must have a reference object.

Important: A disadvantage of the cone shili technique is that it results in blurring of the objectuhich is directly proportional to cone angle. The clearest radiograph is achieved by thc parallelingtcchnique so when thc central beam changes direction rclativc to thc object and the film, the ob-ject becones blurry.

\\'hen trearing multicanaled bicuspids and molars. it is ol'ten difficult to ascertain on theradiograph $hich canal is more toward thc buccal. When a straight-on exposure is taken ofa bi-canaled tooth. thc canals become supe mposed on the filnl, and visualization of each canal is im-possible. Ifthe x-ray cone is moved to give an angled exposure, the roots will bc separate on the

film.By'applying the cone image technique you will be able to determine which canal is thc buccaland rvhich is the lingual.

Explanation of SLOB (Same Lingual, Opposite Buccal) rule; the object toward the lingualside (closer to the liln) will appear to shift on the film to the same direction as the reposi-tioned x-ray cone. For example, ifthe x-ray cone is mesially angulated, the lingual/palatal ob-ject (root) will shilt toward the same (nesiql) side in the resultant radiograph film, and thuswill be easily visualized.Note: Uring this technique you can determine:

l Working length of superimposed canals.

2. Curvatures of root/canals.3. Facial-Lingual orientation ofinstrum€nts, or other anatomical objects.

. Soft tissue exam

. Hard tissue exam

. Radioglaph

. vitality test

. Percussion test

. Mandibular first molars, maxillary first molars

. Mandibular first molars, maxillary second molars

. Maxillary second molars, mandibular first molars

. Maxillary first molars, mandibular first molars

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*** This test is contraindicated. The pcrcussion test is usually not performed bccause ofits paini

however the vitality test will givc you a truly falsc reading, bccause oftcmporary paresthesia in the

area-

For teeth that have becn recently traumatized the dental examination should include:

. Soft tissue exam: observc the lips, face, tongue, etc.

. Hard tissue exam: visually look and then palpate thc injured tooth and alveolus to reveal thc

extent oftooth mobility as well as alveolar fractures and area of inllammation. check for occlusal

disharmonies to hclp detcct tooth displacements andjaw fractures. Radiographic examination; x-rays reveal tooth displacsment and root fracturcs as well as

other important facts (previous rc,ot canal, periapical radioluce cies, elc.).

. Observe the adjacent and opposing tceth for injury'

Teeth that have been traumatized n,lay bc fine for a long tine. however, nany rvill develop radi-

olucencies. Do not indiscriminately do root canals without first checking pulp vitality' and perform

root canal thcrapy only in those teeth that do not rcspond to pulp testing Example: Trauma to

maxillary anterior tcclh. A fcw years latcr x-rays rcveal radiolucencics around the region of thc

apices ofthe incisors. Check the pulp vitality ofall anterior teeth before performin-q root canals'

Note: Trauma tc4r., iry deep intnrsion) to a permancnt tooth will most likely result in necrosis of

the pulp and conventional root canal therapy will be necessary.

Pulpal necrosis: ifcaused by inflammation that started in the pr.rlp /e 81., cdrie.t/, it most probably

will spread to the periradicular tissues; ifcaused by trauma that severs the blood supply to the tooth,

a dry necrosis rnay result that may not spread to the pcriradicular tissues. [t rnay be partial or total:

partial necrosis may present with somc of the symptoms associated with ireversiblc pulpitis

(e.g., a fito-.anale.l tooth could hare an inJlamed pulp in one canal and a necrotic pulp itl the

otrer. Total necrosis is asymptomatic before it affects the PDL, and there is no rcsponse to thcr-

mal or clectric pulp tests. Note: The inflammation will eventually spread beyond the apical fora-

men. which rvill lcad to thickening of the PDL. The clinical manifestation of this presents as

tendemess to percussion and biting

Mandibular molars are characterized by a trapezoidal outline of the pulp chamber. This

outline is formed by two canals in the mesial root and one oval canal in the distal root. lnapproximately 287o (offrst molars) ofthe cases the distal root may have a second canal

(burth canal overal1). The pulp chamber is located in the mesial two-thirds olthe crown.Important: You must look for the fourth canal ifthe first-found canal in the distal root

lies more toward the buccal, instead ofbeing located in the center

I . The lingual wall ofmandibular teeth is most easily perforated when prepar-

ing an access opening due to the lingual inclination ofthese teeth.

2. The mandibular first molar requires endodontic treatment more frequentlythan any other tooth in the oral cavity.

Maxillary molars have a triangle outline of the chamber:. The base of it is formed by the buccal canals, the apex by tlte palatal canal. The line connecting the mesial with the palatal canal is the longest. Ifa fourth canal is present, it is usually located lingual to the orifice ofthe mesiobuc-cal canal. and in the mesiobuccal root. lt is much more common than previouslythought.

.: . ,. 1. The mesiobuccal of the maxitlary molars is the most complex root in the

/l\odr entire dentition because 90o% have either second canals or major fins leading off.a4,^ of the mesiobuccal cana..

2. The maxillary first molar is the posterior tooth with the highest endodon-tic failure rate. The lingual or palatal root is the longest, has the largest diam-eter, and offers the easiest access. The clinician should always assume there are

two canals in the mesiobuccal root until it is proven there is only one.

most oft€n refer prin to the temporal region,

. Maxillary second premolars, mandibular molars

. Maxillary molars, mandibular molars

. Maxillary second premolars, mandibular premolars

. Maxillary molars, mandibular premolars

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Which of the following teeth is most likely to hsve two canals,in facL it has two canals most of the tlme?

. Tooth /14

. Tooth #12

. Tooth #20

. Tooth #28

Coprighr O 2011-2012 - Denlal Decks

Ifcaref'ul diagnosis does not reveal the afl'ected tooth, other teeth and related anatomic struc-tures become suspect. Pulpitis in one tooth may cause pain in other areas

- the pain is re-

ferred.

Slte of Prin Referril Pulp ofTooth Causing Prin

Vcrillrry canincs, rrcrnolJ6

Maxillary sccond prcmola.s

Ear. angle ofjaw, or postelior

Mtrl3l rc8ion ofmandiblc Mrndrbular incisors, canrncs. and prcmolr6

ZygoMtic, par'cral, and occipir.l

Opposing quadmnl or 10 olhertect) in tle sarne quadranl

Maxillary and mandibuhr molari

Important: The nerve endings of cranial neryes Vll, lX, and X are widely distributedwithin the subnucleus caudalis ofthe trigeminal (V) newe. A profuse intenningling ofthesenerve fibers creates the potential fbr the referral ofdental pain to many sites.

Orofacial pain can be the clinical manifestation of a variety of diseases involving the headand neck region. The cause ofthe pain must be differentiated between odontogenic and non-odontogenic. Characteristics of nonodontogenic involvement:

. Fpi:udrc pain with pain free remissions

. Tdgger points

. Pain travels and crosses the midline ofthe face

. Pain that surfaces with increasinq stress

. Pain that is seasonal ar cyclic

. Pain accompanied by paresthesia

Maxiffary first premolars: Approximately 78oh have two roots, one buccal and the otherpalatal, each rvith a single canal. The two roots rnay be completely separate or merely twinprojections rising from the middle third ofthe root to the apex (this is nore comrD,?). The tworoots are usually equal in iength from apex to cusp. However, the lingual root and canal may

be wider.

ln approximately 229lo of maxillary first premolars, only one root is present. there may eitherbe one or trlo canals with one foramen. A cross section at the cervical line shows a canal

shaped like a figure eight /e//rpse). The access opening is a thin oval. Be careful not to per-forate on the mesial (the concavii, on the mesial makes perforation reD'conmon).

The apical foramen ofthe maxillary first premolar is usually close to the anatomic apex, and

rhe apical ponion ofthe roots often taper rapidly, ending in extremely narrou and curved rootrips. The buccal root can fenestrate through the bone, leading to problems such as inaccurate

aper location. chronic post-operative sensitivity to palpation over the apex, and increased riskofan irrigation accident. This tooth is also prone to mesiodistal root fractures and fiactures at

rhe base ofthe cusps, especially the buccal cusp.

Nlarillary second premolars: The most common configuration in this tooth is a single root,occurring approximately 75%o ofthe time. Approximately 25%o ofthe time, two separate rootsare present, each \\,ith a single canal. The access opening is exactly the same as that for max-illary first premolars (thin oval).

Remember: Maxillary second premolars have a higher incidence ofaccessory canals (60'%),

than do maxillary first premolars.

, .. f. When onlyonecanal is present (frst or secotld premolar), it is usually found inrNolce.i fis center ofthe access preparation. lfonly one canal is found, but it is not in the

'*i4d;i center ofthe tooth, it is probable that another canal is present

2. Overfilling either tooth may force materials directly into the maxillary sinus.

. You failed to locate a second mesiobuccal calal

. You failed to locate a second distobuccal canal

. You failed to locate a second palatal canal

. Nothing, it takes more than 12 months for the bone to heal

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Cop)'right O 20ll-2012 - D€nhl Decks

. \{axillary central incisor

. Vandibular central incisor

. \{axillary lateral incisor

. \{andibular lateral incisor

Coptrighl C 20t 1,2012 - Lr€ntat Decks

*** Not only is the mesiobuccal canal the hardest canal to find on tooth #3 and # 1.1, butit also olten splits into t\,'o.

Canal orifices ofa maxillary first molar are arranged in the shape ofa triangle. Tlie ori-fice to the mesiobuccal canal is usually the most difficult to locate, since it is under themesiobuccal cusp and must be entered frorn a distolingual position. This canal is the

small canal and often splits into two canals. lt may be calcified and difficult to instru-ment. The palatal canal is the straightest, widest, and most tapering canal. The most com-mon curvature ofthe nalatal root is to the facial. The distobuccal canal is also small andtapering. The orifice to this canal has no direct relation to its cusp. The distobuccal ori-fice is usually located by means of its relation to the mesiobuccal orifice, t\.'ith the disto-buccal found approxinately 2 to 3 mm to the distal and slightly to the palatal aspect ofthe mesiobuccal orifice.

Note: In approximately 587o ofmaxillary first molar teeth, a fourth canal is present withits orifice being just lingual to the orifice ofthe mesiobuccal canal. The canal is locatedin the rlesiobuccal root and may join the mesiobuccal canal or exit through a separate

fbramen. lf a lesion is present on the mesiobuccal root pior to root canal therapy anddoesn't heal in the usual amount of time (6-12 month.s) following treatrnent, il is rnostlikely due to a missed canal (nesiolingual).

Fracture ofthe maxillary first molar is usually through the central groove or at the base

ofthe buccal cusp. These fractures can extend into the furcation, creating an untreatableperiodontal det'ect.

Remember: The U-shaped radiopacity commonly seen overlying the apex ofthe palatalroot of the maxillary first molar is most likely the zygomatic process ofthe maxilla.

The base ofthe triangle lvill be the f'acial. The apex will be the lingual. llit is not triangular, then rtwill be

oval,

Over 607o olmaxillary ccntril incisors show accessory canals, and thc apical foramen is found apa11 flonrthe apex in .157o of$ese tecth.

ldeal access preparation ofnlaxillary central incisors is ovxl-triangulrr on rhe lingual surface oflhe tooth\\'ilh a sli!ht cune lingually to avoid reducing the incisal edge.

The cenical cross sections below olthe maxillar] permanent teethsho\r the relationship ofthe crown outline to the

pulp chamber and the root canal.

@@@/7-\ ,6,\\0\l \,\0 )l'a\l/ \r'

Firn Prcmohr Second Prcmolar

./=-\ F:ltl nl\ll /1 llu u l) U U il\-/ \r'

First luolar S.cond ltol.r

.5%

.20%

.45%

.65%

. The first statement is true, the second is false

. The first statement is false, the second is true

. Both statements are true

. Both statements are false

t5CopFighr O 20ll-2012 - Dent.l Decks

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Copyrighr O 201 l-2012 - D€ntal Decks

*** Almost one fourth ofall mandibular first oremolars mav have two canals with two foram-ina.

The treatment of mandibular first premolars can really be tricky! At least 27oA may havetwo canals with either one or two fommen. This is quite different from the mandibular secondpremolar

-867o are found to have one canal with one foramen.

The second premolar has fewer variations than the fimt premolar, usually having one root andone well-centered canal. The access opening is oval. Consideration must be given to the men-tal foramen which lies in close proximity to the apex. Avoid overinstrumentation and over-fill. When viewing an x-ray ofthis area, the mental foramen is sometimes misdiagnosed as a

premolar abscess. Therefore, before performing root canal therapy, make sure all diagnostictests confirm your finding.

Note: Ifa straight-on preoperative radiograph ofa mandibular first premolar shows the pulpcanal disappearing (or goingfrom dark lo /r'g@ in midroot, this is an important indicationthat two canals are present

Other diagnostic tests:. S€lective anesthesia test: can be used when other tests have not determined which toothis the source ofpain.. Test cavity: only done in cases where a strcng suspicion ofpulp necrosis is present andconfirmed with other tests and radiographic findings, but a definitive test is requircd.

Remember: A radiolucency will not begin to manifest until demineralization ofbone extendsthrough the cortical plate ofthe bone

-Key point: You should not rely exclusively on x-rays

in an anempt to anir e at a diagnosis.

lmportant: Because an x-ray is only a two-dimensional image, two films ofthe tooth or teethin question should be taken at the same vertical angulation but with a 10- to l5-degree changein horizontal ansulation.

Mandibular canines usually have only one root but in rare cases may have two separate

roots. The access opening is a large oval with the greatest width placed incisogingivally.

This tooth usually has a slightly labial axial inclination of the crown, therefore the ac-cess opening needs to be directed towards the lingual surface.

The canal ofthe mandibular canine is somewhat ovoid at the cervical area but it becomes

rounder at the apex.

\ote: The root canal for a mandibular canine is thin mesiodistallv but wide labiolin-guall)'.

. Maxillary central incisor

. Maxillary lateral incisor

. Maxillary canine

. Mandibular central incisor

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Coplright @ ?01 1-201? , Denial Decks

. Control the hemonhage with hemostatic agents

. Apply formocresol with cotton pellets at the amputation site

. Irrigate the canal with sodium hypochlorite then apply calcium hydroxide

. Perform the amputation at a more apical level

. Stop the procedure and close the tooth with an interim restoration

. All of the above

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Coplright O 20ll-2012 - Denral Decfts

The maxiiJary lateral incisor ahvays h{s f99.9Zo) one root with one canal. The root is more slender thanin the maxillary central incisorand frequently 1557,y' has a distal and/or lingual curvature or dilaceration.The access opening is oval.

Maxillary central incisor: The maxillary central incisor always has one root and one canal. The rootis bulky, with a slight distal axial inclination but rarely has a dilaccration. The access opening is oval-triartgular.Maxillary canine: The maxillary canine always has one root and one canal. This tooth is the longestin the arch. The access opening is o\al.Note: The maxillary central, lateral, and caninc roots and hence, canals all have a distal axial inclina-tion. This mcans in pcnetrating along thc long axjs ofthe tooth, the bur must be slightly angled towardthe distal surface. Failure to do this may lead to perforation ofthe mesial portion ofthe root.

Remember: The mandibular incisors (latemls and centrals) ha're only one root which is narrowmesjodistally but relatively wide labiolingually and may have a distal and/or lingual curvature. Twocanals may be present. When there are two canals, the labial canal is the straighter one. The access

opening for a orandibular central or lateral is a long oval, with the greatest width placed incisogingivallyand the incisal extent very close to the incisal edge.

Perforation: Although many errors can potentially occur during acccss preparations, the most deictcri-ous is perforation ofthe pulp chamber space into the oral cavify or periodontal tissues. Ifthe perforationoccurs above the osseous crest in the gingival sulcus or above the free gingival margin, consider thefollowing measures: (l) Control hemorrhage with a dry cotton pellet or some hemostatic agent, do notuse formocrcosol (2) Scalwidl a temporary cement, such as Cavit orZOE, (3) Procccd with RCT (4) Planto restore perforated area separately or make such restoration part of the final tooth preparation. Ifthepedoration is at or below the osseous crest or into the furcation region, thc following steps can bc con-sidered; horvever, the prognosis for thcse cases is very poor (l) Seal the perforation immediately (2) Ifthe pcrforation is close to a canal orifice, place a file, gutta-percha cone! or silver cone into thc canal toprcvcnt the placement ofmaterial in the canal during the repair (3) Control the hemorrhage, if it can notbe controlled due to size the[ use a pulp capping agcnt, such as Dycal, if it is controllable, use Cavit orZOE to seal perforation (4) Try to avoid pushing any sealing materials into the periradicular tissues.

*** Uncontrolled bleeding is a sign ofinflamed pulp tissue. The radicular pulp must beuninflamed for the success ofthis procedure. It is not uncommon to find uninflamed pulpat a more apical level, especially in cariously exposed teeth. If bleeding does not stopeven after more apical amputation, hemostatic agents are used as a compromisetreatment. These are closely monitored and if vitality is lost, apexificatiorr (pulpectomy)

procedures should be instituted.

Pulpotomy is the surgical removal of the coronal portion of a vital pulp to preserve the

vitality ofthe remaining radicular pulp. The common indications include:. Cariously exposed deciduous te€th

-with healthy radicular pulps

. Traumatic or carious exposure ofpermanent teeth with undeveloped roots

. An alternative to extraclion when endodontic treatment is not available

. Emerg€ncy treatment in permanent teeth with acute pulpitis

Unfortunately, pulpotomy procedures performed in fully developed permanent teethare not found to be successful. For this reason it is regarded as a temporary procedure inthese teeth.

. Accidental exposue of the pulp

. Pulp ofa middle-aged person

. Carious exposure ofthe pulp

. Pulp ofa young child

. Lack ofan apical stop

. An abnormally large apical portion of the canal

. An inegular apical portion of the canal

. After an apexifrcation procedure

. All of the above

20Coptriglt @ 201l-2012, D€nral Deck

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Coplright O 20ll-2012 - Dertal Lrecks

Pulp capping is the placing of a sedative and antiseptic dressing on an exposed healthy pulp inorder to allow it to recover and maintain normal function and vitalit),. The dressing most com-monly used is CaOH2 (Dycal). Pulp capping is overuscd in dcntistry today. ln reality it has onlyvery l-ew indications for its use. Young pulps are morc vascularized and. therefore, more amenableto repair. Pulp cappjngs are more successful if the exposure was acc idental (trduma or \r ith a de -la1Dr, as opposed to carious. ln addition, the exposure should only be pinpoint lo expecl succcss.Repair is accomplishcd by the formation ofa dentin bridge at the site ofexposure. Evcn a snallcarious cxposurc should have root canal therapy for thc best long-term prognosis.

Note: Direct pulp capping is indicated ifthere is a small mechanical exposure for.snall traLtmaticexpo.\ure), an asymptomatic vital pulp, and no coronal or periapical pathology. A hard tissuc bar-ricf (repuratlw dentin bridge) may be visualized as early as 6 weeks postoperative.

Atooth may stay asymptomatic for scveralweeks after pulp capping has bccn pcrformcd. However,this may be only tenrporary. Unfortunatcly, if pulp capping I'ails and the tooth becomes sympto-matic, it may be difficult, ifnot impossible, to treat with routine endodontics because oflhe severccalcifications in the root canal. Perforations may occur during attempts to follow the obliteratedcanal to gain palency to the apex. Note: Perfo.ations into lurcations ofmulti-rooted tecth havc thepoorest prognosis.

Indirect pulp capping involves removing infccted dentin almost up to the point ofpulpal expo-sure. Calcium hydroxide is placcd and then a resin modified glass ionomer cement is placed overthat. Formation of secondary dentin should occur and then a final restomtion is placed alicr rcmovalofthc internlediate restoration and rcsidual carics. Thc goal ofindirect pulp capping is to havc thctooth participale in ils own recovery. Indications for indirect pulp capping include deep cariouslesions that encroach but are not actually in the pulp, no history ofchronic pain, no radiographicpathology'. r'ital pulp. and normal looth mobility and color

Ifthe preparation is properly flared, fitting the master cone is not a time-consuming pro-cedure. A gutta-percha cone the same size as the file used last durin gpreparation (MAF)is selected and placed as far as possible into the canal, but not beyond the working length.Once satisfactory tugback and apical positioning appear to be obtained, a radiograph istaken to verify cone positioning. If an accurate determination and careful enlargementhave been performed, the x-ray will show that the master cone reaches the most apicalposition of the preparation or extends to a point just short of that ( I nm). When thecone is slightly short, the pressure ofcondensation plus the lubricating action ofthe sealer* ill be sufficient to produce complete seating of the cone.

L If the cone is more than I mm from the radiographic apex, discard the cone\rl3es and fit a smaller one or instrurnent more in the apical third.. 2. Remember: The main reason for recapitulation lirirgl,our MAF after eqcll

inct euse in .;file size) during instrumentation of the canal is to clean the apicalsegment ofthe canal ofany dentin filings that lrere not removed by irrigation.3. Common solvents used to soften gutta percha are chloroform, methylchloro-formate, halothane, rectified white turpentine, and eucalyptol.4. Studies show that solvent softening does not ultimately result in a better api-cal seal.

5. Slight resistance to dislodgement is refened to as 'itugback.r'6. The cone should also have a delinite apical seal - it should not be able tobe pushed further apicall,.

. Continue with obturation, the anesthetic is simply wearing off

. Continue with obturation, this is a normal complaint during this part ofthe procedure

. Consider looking for an accessory canal and re-filing, there is likely pulpal tissue thathas not been properly debrided

. Inigate furtheq the Sodium Hlpochlorite should take care ofthis problem

. Temoorize the tooth and obturate at a later date

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\

. Urea peroxide (Gly-Oxide)

. Hydrogen Peroxide

. Sodium Hypochlorite

. Calcium Hydroxide

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*** This indicates inadequate debridement, as a pulpless tooth should not respond to anystimuli.

The most important consideration before filling a root canai is prop€r cleaning (debride-ner, and shaping (instrumentin&) ofthe canal. Once the canal is obturated, any organismsthat have entered the periapical tissues from the canal are eliminated by the natunl defenses

ofthe body.

Objectives of root canal obturation:. To develop a fluid-tight seal at the apical foramen. Complete filling ofthe root canal space. To create a favorable biologic environment for the process oftissue healing

ln endodontic treatment the importance ofcanal obturation (/i//,rg) is second only to canaldebridement friic h is the ke! to succe$. Approximately 40% offailures are believed to be

caused by incomplete obturation ofthe root canal. lfthe canal is not filled, tissue flr,rid and mi-croorganisms from the periapical tissues are able to enter the voids, with failure as the ultimateresult. Howeyer, if an accessory canal is not totally filled during obturation, the appropri-ate treatment is to observe the tooth and evaluate every three months.

Remember: The presence of a periapical lesion before root canal treatment will reduce thesuccess rate of the treatment by 10%-20%.

Note: After endodontic therapy is completed on a tooth with a periapical radiolucency, it nsu-ally takes 6-12 months before marked reduction in the size ofthe radiolucency is evident onan x-ra.v. Desired periapical tissue changes include regenention ofalveolar bone, depositionof aoical cementum. and re-establishment ofthe PDL.

preparation for many years. A 5.25olo solution provides excellent germicidal solvent ac-tion, but is dilute enough to cause only mild irritation when contacting periapical tissue.

NaOCI is a good tissue solvent as well as having some antimicrobial effect. It also acts as

a lubricant for root canal instrumentation. Note: lt is toxic to vital tissue; always use rub-ber dam. Note: To date there is no agreement on any single concentration-value ofsodium hypochlorite Q"taOCl) as being the most effective while being the safest.

H"vdrogen peroxide (396 solution) is also widely used in endodontics with two modes ofaction. The bubbling of the solution when in contact with tissue and certain chemicalsphysically foams debris from the canal (efJbnescent eflbcf. In addition, the liberation ofoxygen uill destroy strictly anaerobic microorganisms. The solvent action of hydrogenperoxide is much less than that ofNaOCl. However, many cljnicians use the solutions al-temately during treatment.

Urea peroxide is available in an anhydrous glycerol base, as Gly-Oxide, to preventdecomposition and is a useful irrigant. It is better tolerated by periapical tissue thanNaOCl. yet has greater solvent action and is more germicidal than hydrogen peroxide.Therefore, it is an excellent iffigant for treating canals with normal periapical tissue andri,'ide apices. The best use for Gly-Oxide is in narrow and/or curved canals, utilizing theslippery effect of the glycerol.

Note: Irrigants perform the important biologic function of destroying bacteria duringendodontic therapy. Their action is unquestionably more significant than that supplied bythe use ofintracanal medicaments. Irrigants should be used copiously throughout the in-strumentation phase ofroot canal procedures.

*** Calcium hydroxide is not an irrigant.

Sodium Hypochlorite is the most widely used irrigant and has effectively aided canal

. Rotary files

. Chloroform

. Glass bead sterilizer

. Ultrasonic

. Heated instruments

24Coplrighr O 201 l-2012 - De al Deks

. It is a chelating agent with the capability to remove the mineralized portion ofthe smearlayer

. It can decalcifu up to a 50 pm thin layer ofthe root canal wall

. Normally it is used in a concentration of l7o/o

. RC-Prep and EDTAC are other preparations of EDTA

. The decalcifying process induced by EDTA is selfJimiting

. It is also an excellent irrigation solution

25Coplrighr C 201l-2012 - Dental D€cks

Techniques to remove gutta-percha include:. Rotary removal. Ultrasonic removal. Heat removal. Heat and instrument removal. File and chemical removal

Chloroform is the reagent of choice to dissolve gutta-percha. [t is very effective butshould be used with caution. Its vapor is potentially hazardous, so it is dripped directly inthe canal avoiding excessive flooding.

Other chemicals which can dissolve gutta-percha to a varying degree include: xylol,halothane, benzene, carbon disulfide, essential oils, rrethyl chloroform and white rectifiedturpentine.

If a gutta-percha cone has passed beyond the ap€x then a file must be used beyond theapex in order to avoid breakage ofthe cone. A broken cone in the periapical area may re-sult in an orthograde re-treatment lailure.

,'Notes,

l. Gutta-percha points may be disinfected by placing them in a 5.25% NaOCIsolution for one minute.2. A glass bead sterilizer can sterilize endodontic files in l5 seconds at 220'

c u2n F).

*** This is false; it has a limited value as irrigation solution. The decalcifying process in-duced by EDTA is selfJimiting and stops as soon as the chelator is used up.

Chelating agents are used to aid and simplify preparation for very sclerotic canals afterthe apex has already been reached with a fine instrument. These agents act on calcifiedtissues only and have little effect on periapical tissue. Their action is to substitute sodiumions, which combine with the dentin to give soluble salts for the calcium ions that are

bound in less soluble combination. The edges of the canal are thus softer, and canal en-

largement is facilitated.

EDTA will remain active in the canal for 5 days if not inactivated. For this reason, at thecompletion ofthe appointment the canal must be irrigated with a sodium hypochlorite(NTOCl) containing solution. Note: Rinsing for I minute with EDTA eliminates thesmear laver, opens dentinal tubules, and provides a cleaner surface for gutta-percha

and sealer to adapt.

EDTAC is EDTA with the addition of Cetavlon, a quatemary ammonium compound. lthas greater antimicrobial action than EDTA. However, it has greater inflammatory po-tential to tissue as well. The inactivator for EDTAC is NaOCl.

RC-PREP combines the functions ofEDTA plus urea peroxide to provide both chela-tion and irrigation. The foamy solution has a natural effervescence that is increased by ir-rigation with NaOCI to aid in the removal oldebris.

. To obtain clean shavings of the canal

. To attain a clean irrigating solution

. To achieve glassy smooth walls of the canal

. All ofthe above criteria are reliable

. None ofthe above criteria is acceptable

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cop)righr O 20ll-2012 - Dental Decks

While cleaning and shaping the canal, an instrument seperat$ in the canal.As you rttempt to retrieve it, the broken instrument passes partiallythrough the rpex, tbus partly protruding into the periapical lesion.

How do you manage this case?

. Use a smaller H file to bypass it and try retrieving it

. Use Gates Glidden drills to widen the canal and then try retrieving it

. Raise a flap and remove the instrument surgically followed by gutta-percha filling thecanal

. Extract the tooth as irreparable damage has occurred to the apex

. Just inform the patient, fill the canal with gutta-percha and monitor

27Coplright O 20l l-2012 - Dental Decks

*** Clean shavings are difficult to see on a file. The attainment of a clean irrigating so-lution is considered an inaccurate way to determine the end point ofdebridement.

Debridement is defined as the removal offoreign material and contaminated or devital-ized tissue from or adjacent to a traumatic infected lesion until surounded healthy tissueis exposed. Chemomechanical debridement of the root canal system is the most crucialaspect ofroot canal treatment.

Complete debridement of the canal is the most effective means to reduce root canalmicroorganisms. It can be carried out in various ways as the case demands, and may in-clude instrumentation ofthe canal, placement ofmedicaments and irrigants antVor surgery

Remember:. The most common cause ofroot canal failure is incompletely and inadequately disin-fected root canal systems.. The second most common cause of failures ol root canals is leakage from a poorlyfilled canal. This is common even after apical curettage. Example: Root canal treat-ment performed on a tooth with apical curettage ofa lesion that was found to be a cyst.Three years later the lesion is even bigger than it was before. The most likely cause ofthis lailure is leakage from a poorly filled canal.. A ledge is an artificially created irregularity on the surface ofthe root canal wall whichprevents the placement ol instruments at the apex ofan otherwise patent canal. Ledgingis caused by insertion ofuncurved instruments sl'lort ofthe working length with excessiveamounts ofapical pressure. The canal wall is gouged or a false canal is created which re-

sults in ledge formation. The effective use ofcircumferential filing, especially with Hed-strom files, will ensure smoothness and occlusal flaring ofthe canal walls and prevent thederelopment of steps or irregularities.

Cenerally, when a broken instrument protrudes past the apex, surgery should be

performed. This constant iritant must be removed.

Note: It is relatively easier to retrieve an instrument if it is wedged coronal to thecurvature or at the curvature ofthe canal but verv difficult if it has Dassed the curvature.

When an instrument breaks off anrvhere in the canal and a periapical radiolucency ispresent and rninimal canal enlargement has been performed before the accident, surgeryis indicated since the periapical tissues have had little opportunity for h€aling to be

stimulated. You would prepare and obturate to the point of blockage and then performan apicoectomy and retrofilling.

However, rvhen an instrument is broken off in the apical third and is lodged tightly withno periapical radiolucency evident, the remaining root canal space can be filled. Thepatient should be informed ofthis and placed on a 3-6 month recall.

Important: Prognosis ofa tooth with a broken instrument is best if the tooth had a vitalpulp and no periapical lesion.

. Push and pull stroke

. Reaming motion

. Engine-driven rotary motion

. All ofthe above

. Non-staining property

. Fast setting time

. Adhesion

. lnsolubility

. Long history ofsuccessful usage

2a

Coplriglt @ 201 1,201 2 - Dmral Deck

29

Cop)'ri8hr e 201 I '2012 - Dental Decks

*** The engine driven instruments, however, use only the reaming motion. Nickel tita-nium instruments can be both hand operated and engine-driven.

Generally, hand instrumentation is done by either filing (push and pull) or reaming 6e-peated rotqtions).

Filing is a push-pull action with emphasis on the withdrawal stroke. Its efficiency is great-est with fil€s than with reamers for removing dentin because of the greater number offlutes in contact with the canal walls during the rasping motion of removing the instru-ment. Filing action produces an irregularly shaped canal and therefore must be filledwith gutta-percha in a condensation procedure.

Reaming is defined as the repeated clockwise rotation of the instrument, particularlyduring insertion. Reaming produces a canal that is round. Reaming is recommended ifusing a silver cone to fill canals.

Circumferential filing is a push-pull action with emphasis on scraping the canal wallsto create a smooth, tapered preparation. It is a method of filing whereby the instrumentis moved first towards the buccal side ofthe canal, then reinserted, and removed slightlymesially. This is done all the way around the tooth until all the dentin walls have been

planed. This technique enhances preparation when a flaring method is used.

Remember: The primary function ofa root canal sealer is to fill in the discrepanciesbetween the core-filling material and the dentin wall. In fact it is said that it is more im-portant than the core filling material.

Other purposes or functions ola root canal scalcr includc:. To act as a lubricant, facilitating placement ofthc gutta-pcrcha. To form a bond between the filling material and the dentin walls. To exert antibacterial activity (some exert more than others). This activity is thehighest in the period of time immediately aft€r its placement.

Most root canal scalers are some type ofzinc oxide-eugenol cement and are capablc ofproducing a seal whilc bcing well-tolerated by periapical tissues.

All sealers display some degree of radiopacity (caused by metollic sahs in the sealer);thus are visiblc on a radiograph. This helps disclose the presence of accessory canals, re-sorptivc arcas, root fracturcs, and thc shapc ofthc apical foramen and other structurcs oflnterest.

Note: After filling a tooth with gutta-percha, if you see a horizontal line of firaterial(gutta-percha or sealer) extending both mesially and distally from thc canal to thc pc-riodontal ligament space, this is indicative of a root fracture.

ZOE disadvantages: staining, slow setting time, non-adhesion, solubility.

. Maxillary first premolar - mesial concavity

. Maxillary molar - proximity of canals to mesio-buccal line angle

. Mandibular molar - mesioJingual tilt of tooth

. Mandibular incisor - small buccal-lingual dimension

30

Cop)'righr e 201 l'2012 - Dental Decks

. The first statement is true, the second is false

. The first statement is false, the second is true

. Both statements are true

. Both statements are false

31

Coplright O 201 l-2012 - Dental Decks

Major objectives ofthe access preparation:

l. StraighGline access

2. Conservation of tooth structur€3. Unroofing ofthe chamber and to remove pulp horns

Access to the root canal is the initial step in canal preparation. It is necessary to estab-Iish straight-line access to the apical foramen to ensure free movement ofthe instrumentduring debridement and preparation ofthe canal. A1l the treatment that follows hinges onthe correctness ofthe access preparation. All access cavities are made through the lingualon anterior teeth and through the occlusal on posterior teeth.

Note: A facial approach is recommended for an access opening on maxillary primaryincisors.

Remember: Mandibular incisors and maxillary first premolars require the most careto avoid perforation during preparation ofthe access opening. This is due to the narrowmesio-distal dimension ofthe rnandibular incisors and the mesial concavitv ofthe max-illary first premolars.

Important: During access preparation on mandibular molars, lhe following two re-gions tend to be "overcut" which results in the undesirable over preparation ofthe tooth:

. The mesial aspect under the marginal ridge

. The lingual surface under the lingual cusps*** Mandibular molars tip mesially and lingually. Ifa bur is directed straight inferiorit may cause unnecessary loss oftooth structure ftom the these areas.

Studies have shown that the action of using thc instrunent, rather than the instrument used, de-termines the general shape ofthc canal preparation. Therefore, a reaming action produces a canal

thal is relatively round in shape while a filing action produces a canal that is irregular in shape.

Important: A canal should be instrumented and shaped so that it has a continuously tapering fun-nel shape. The widest diameter would be at the canal opening and the narrowest at the dentinoce-mental j unction aJ I o L0 mm from the radiographic aper). This is where all teeth should be filedto and fillcd to fideal/r.

The common methods for sterilization uscd in cndodontics are:. 2 1/o Glutaraldehyde:

- Cold or heat-labile instruments such as rubber dam frames. etc.- Generally, 24 hours are required to achieve cold sterilization.- Least desirable mcthod.

. Autoclave:- Instrurnents should be wrapped and autoclaved for 20-30 minutes at 250' F ( I 2 I' C) and 15

psi.

- This *ill kill all bactcria, sporcs and viruscs.

. Dr-v heat sterilization:- Is supcrior for sterilizing sharp-edged insltruments (hand instruments, fles, reamers, broaches,D&ri. etc.l to best preserve their cutting edges.- Temperature is 320" F (160" C) fbr a minimum of I hour- Dry heat is effectivc as a stcrilizing agcnt becausc the resistancc ofproteins to heat denatFration decreases as they dry.

. Hot salt {or beads):- Bead sterilizers are receptacles that heat contents to approximately 45O" F (232" C).

- lntracanal instruments (iles, reamers, broaches, etc.) shouldbe stcrilized by immersion in thesalt for 5 seconds.

. Both the statement and the reason are correct and related

. Both the statement and the reason are correct but NOT related

. The stalement is correct, but the reason is NOT

. The statement is NOT correct, but the reason is correct

. NEITHER the statement NOR the reason is correct

32

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. Plasma cells

. Vacrophages

. Lymphocyes

. Polymorphonuclear (PMN) Leukocytes

Copj,right O 20ll-2012 - D€nral Decks

*** The rcason broaches are not used for canal cnlargcmcnt is not becaus€ they are made ofstainless stccl.it is lheir design.The barbs are notchcd out of the instrument shaft and rcpresent a weaken€d point. If thebroach is not used with the utmost of car€ or il it is forced apically, the barbs will be bent and will engagethe walls, making removal difficult. It is not used for canal enlargemenf.

K-type instruments:. Files are lhe most uscful instruments in eDdodontics fbr the removal ofhard tissue in canal enlargements.They arc manufactured by t$isting a blank, which is a square rod. producing a series ofcutting fluies. Theaction uscd for placing this type offile into a canal should rescmble a clock \1 ise-counierc lock*,ise motionwith pressure dircctcd apically (tan he a.filing or reaning action). Note: These files are the strongest ofall files ancl cut the least aggressiv€ll. A modification to this tlpe oftlle is the K-fl€i file.

. R€amerc are manut'actured in a manncr similar to files. only they have fe*er flutes. They are used incanal preparation to shave dentin and enlarge cmals \r,ith a rcaming action only, They remove intracanaldcbris with clockrvise reaming action. They arc also uscd to place materials into the apical ponion of thecanal by using a counierclocklr'is(] rotatlon.

H-type instruments:

. H€dstrom files are manufactured by using a sharp, rotating cutter to gauge triangular s€gments our ofaround blank shaft. This produces a very sharp edge and thereforc an cffective cuiting insrument. Ifused care-tully, lvith filing action only, it \\'ill successtully planc rhc deniin *alls much faster than K-rype files orreamcrs. A modification oflhis filc is the S-file.

\ote: All ofthe above are made ofsteinless st€el.

File dimenrions: The position at which the cutting bladcs begin on an instrument is called Dl, aDd thc flutcs.\tcnd up rhc shafl fbr 16 mm to stop at D2. The remaining portion ofthe shaft extendiig io the handle has nollutes. and its length is the difference between 16 mm. and the lotal lcngth from lhe tip to the handlc. Theleneth of cunin.e edgcs lthe distance beteee D t a d Dt remains l6 mm, regardless ofthe lcngth or style ofIhc i:sirument. The numbcring svstem for instrument identification is based on the diameter at Dl, stated inhurdredths of millimeters. Therefore the name ofeach instrumcnt givcs considerable inlormation about its di-merioni Asjzel0fleisindicatedtobe0.l0mminwidthatDt and . l0 mm plus 0.30 mm (or 0.10 mn) ar

3 lornt 16 mm f'arther up the shaft fDr, etc.

The onset ofpulpal inflammation is an insidious process and is characterized by a chronic cel-fufar response fplasmq cells, macrophages and l,vmphoq'tes). There is no direct exposure ofthe pulp to dental caries and the response, therefbre, is not acute. After pulp exposure, theacute inflammatory cells (nainly PMN celA, are chemotactically attracted to the area. Histo-logicalh, the tissue is likely to show signs ofacute inflammation near the site ofthe exposureand a band ofchronic inflammatory cells between the acute inflammation and the underlyingnormal pulp.

The response ofvital pulp to microbial invasion is very resistant. Based on the observationIhaI e\ en alier t$,o weeks of tmumatic pulp exposure, only 2 mm of coronal pulp may "givein" to microorganisms. Non-yital pulp, in contrast, is a "fertile ground" for the growth of mi-croorganisms.

Remember: Carious exposures in permanent teeth generally require root canal treatment. Im-matld(e (open qper) pennanent teeth with carious exposures can be treated by pulp cappingor pulpotomv procedures.

Important: Pulp capping is not recommended in primary teeth with carious exposures dueto its high failure rate and because pulpotomy, having similar time requirements. has shownto be very successful. Pulp capping can be done, however, in mechanical exposures.

1. Calcium hydroxide has a high pH of 12.5 which cauterizes tissue and causessuperficial necrosis.2. This necrotic zone encourages the pulp to induce hard tissue repair with sec-ondary odontoblasts laying down reparative dentin.

. Condensing osteitis

. A vertical fracture ofthe tooth

. Periodontal abscess

. Secondary occlusal trauma

34CopFigh O 201 l'2012 - Dental Decks

. The first statement is true, the second is false

. The first statement is false, the second is true

. Both statements are true

. Both statements are false

35Copltighi o 20l l-2012 - Dental Decks

Radiographic examination seldom reyeals the fracture because the crack is usually parallelto the x-ray film. One of the most puzzling and frustrating dental conditions involving thepossible need for endodontic treatment is the cracked tooth syndrome. Symptoms from thiscondition usually are characterized by a sharp but brief pain occurring unexpectedly onlywhen the patient is chewing. Having a patient bite forcefr.rlly on a bite stick and noticing thecusps that occlude when the pain occurs will aid in the location ofthe olTending tooth.

In most cases there is an isolated probing defect at the site offracture. An important diagnos-tic sign is a radiolucency from the apical region to the midline of the root (J-shaped orteardrop-shaped). Vertical fractures through rcot structure, however, have an almost hopelessprognosis. lfthe fractured segment can be removed and gingivoplasty and alveoloplasty per-fbrmed, treatment can be successful. However, unrealistic or overambitious case selectionleads to a high degree offailure.

When an anterior tooth fractures, it generally occurs in a more horizontal plane and mayshow up on the x-ray. The cause is usually accidental tnuma such as a blow to the jaw orteeth. If the fracture line is not too far down the root ofthe tooth. it mav be able to be savedwith a root canal and a crown.

lmportant: Inlays have been shown to be a cause offractures. lfa patient complains ofpainon mastication since the placement ofan inlay, suspect a fractured cusp /asltg n b ite stick willhelp detemtine v'hiclt cusp may be fracnred).

Itiote: Chronic focal sclerosing osteomyebtrs (condensing oJleillt is excessive bone mineral-ization around the apex ofan asymptomatic, vital tooth. This radiopacity may be caused by alo$.erade puip initation. This process is asymptomatic and benign and does not require rootcanal therap!.

*** Hydrogen peroxide is the most effective bleaching agent; used in concentrations of30-50%. lt is best delivered in an alkaline medium.

Superoxol is a 307o aqueous solution by weight ofhydrogen peroxide in distilled water.It is potent oxidizing agent whose bleaching effect results from direct oxidation ofstain-producing substances.

Chairside technique: Application of heat to Superoxol-saturated cotton pellets in thetooth chamber Repeat until tooth is lighter Note: The heat liberates the oxygen in thebleaching agent.

Important:. Cervical root resorption relating to bleaching is a potential side effect; usually itdoes not manifest for at least 6 months. This is a reason why recall appointments are

lmponant.. The most probable postoperative complication of bleaching a tooth that has notbeen adequately obturated is an acute apical periodontitis.. Tooth bleaching causes a color change in both enamel and dentin.

\lalking bleach technique: uses a mixture ofsodium perborate and water and may beutilized ifthe chairside results are inadequate or ifyou prefer to avoid the possibility ofahigher chance ofcervical root resorption. Place a thick paste in the tooth chamber with atemporary restoration for four to seven days. Several repetitions of this procedure canwork quite well. The sodium perborate when fresh is 95olo perborate giving off 9.9% ofavailable oxygen. This material is more easily controlled and safer than Superoxol; there-fore, it is the material ofchoice.

Tooth # 9 requires root-end surgery. Whichllap design is generally lr'Ol indicated?

. A submarginal curved flap (semilunar)

. A submarginal scalloped flap (Ochsenbein-Luebke)

. A fulI mucoperiosteal flap (triangular, rectangular, trapezoidal, horizontal)

. None of the above

Copyrighr Q 2011'2012 - Dmral Decks

In which of the following cases could a dentist choose not toperform root canal th€rtpy rlthough it is advised?

. On a non-restorable tooth

. On a periodontally insufiicient tooth

. On a tooth with a vertical root fracture

. On a asymptomatic tooth with a calcified chamber

. On a tooth that is not in occlusion

. On a tooth that has massive extemal resorption

Cop)right O 20ll-2012 - DentalDecks

This half-moon shaped flap is raised with a curved horizontal incision in the mucosa or attached gin-gival with the concavity towards the apex. Although it's simpie and does not impinge on the surround-

ing tissuc, thc disadvantages outweigh its advantages. These include:. Limited access and visibility. Tcaring of comeN ofthe incisions when an attempt is made to improve accessibility by stretchingthe flap. Ifsomehow a lesion is found to be bigger than anticipated, the incisions come to lie over the bonydefect. Its extent is also lirnited by anachments 1/e.g.,.fienum, muscles etc.)*** Tlterefo.e, this tcchnique is not used for anlerior root end surgery.

Surgical flaps on the basis ofhorizontal incision can bc classificd into tr}o major typesiL Full mucoperiosteal flaps:

. Triangular (one vertical releasing inci.sion) . Trapezoidal (brctal hased rcctanguldr)

. Rectangular /ano t,erlical reledsing incisior.t . Horizontal /ro rcfiical rcleasing incisions)

2. Limited mucoperiosteal flaps:. Strbmarginal cuned (Senihnar). Submarginal scallopcl ( Oc hsenbei n- Luebke)

The submarginaf scalloped (Ochsenbein-Le!6te, tlap requires at least 3-5 mm ofattached gingiva anda hcalthy periodontium. It is raised by a scalloped incision in the aftached gingiva with onc or two ver-tical incisions. Less risk ofincising over bony defects and no post-surgical recession ofgingiva. Its dis-advantages includc hcmorrhagc from the cut margins and scarring. Access and visibility is better fdrdacceptoblel than semrlunar flap but not as good as full mucoperiosteal flap.

Full mucoperiosteal flaps allorv maximal access and visibility. They are raised from the gingival sul-c\rs (ele\!ting gingirdl crest and interdental glrg,?,/. This wide outliI1e ofthe flap prccludes any inci-sions o\'cr bonv defects and allows various periodontal procedures including curettage. root pianing andbone re-shaping. A large flap may be difficult to reposition, suftrrc and makc alterations. Posr surgical gin-si\ al recession is also a oossibilitv.

*** ln all thc othcr sccnarios. root canal therapy is contraindicated.

Other contraindications include:. A non-strategic tooth

-a tooth not in occlusion

. A tooth with massive internal or external resorption

.A tooth that has a canal unsuitable for instnlmentation or forsurgery /i.e., broken instnrnents,dentina l sc lerosi|;, s hat p d[l a. erations, etc..)

A medical condition such as hcmophilia is not a contraindication to convcntional endodontic ther-apy. However, it is strongly recommended that a dcntist obtain clcarance from the patient's physi-cian prior to trcatmcnt. Thc only systemic conlraindications to endodontic thcrapy are

uncontroffed diabetes or a very recent myocardial infarction (v,ithin tlte post 6 months).

Note: Example of a special case: A previously traumatizcd looth may show complcteobliteration ofthe pulp chamber and canal. The periodontal ligament may appear non'nal. The pa-tient will be asymptomatic and the tooth will not respond to pulp vitality testing. The trcatment ofchoice is to obsene as long as the tooth remains asymptomatic and no periapical changes arc cv-rdent.

Fracture injuries:. Infraction: an incomplctc crack ofenamel wilhout thc loss oftooth structluc. Enamel fracture frIis Class I)t involves enamel only: no pulpal involvemcnt. Enamel and dentin fraeture (Ellis Cla.t,r 1/): involves enamel and dentin; no pulpal involvc-tnent. Enamel and dentin fracture with pulpal involvement ft1lr.r Class III): pulpal trcatment de-pcnds on stage of developrnent oi' tooth (immatrre $ msture) and ti]me after traumatic injury/lfter 21 hours the chances ol direct bacterial contdmii.ttion increase). Root fractures: prognosis dcpcnds on location; coronal root liactures ha!c a poor prognosis,n]idroot fracturcs havc guarded prognosis and apical root fractures havc the bcst prognosisImportant: Prognosis improves as liacturc approaches apex: horizontal is better than vertical;nondisplaced is bctter than a displaced fracturei and oblique is bettcr than transversc.

. A conical shaped probing

. A narrow sinus tract type probing

. A blow-out type probing

. None ofthe above

38

CoDriglr O 201 I -20 12 - Dental Decks

. A major disadvantage of posts/dowels is that it does not reinforce the tooth structure,

in fact, it weakens it

. All post designs are predisposed to leakage

. At least 4 mm ofgutta-percha must remain to pr€serve the apical seal

. Threaded screw posts are preferred over parallel sided and tapered posts

. Pins add to stresses and microfractures in dentin and should not be used

. Cusps adjacent to lost marginal ridges should be restored with an onlay

39

Coplai8hr o 201 l-2012 - Dental D€cks

*** In "blow-out type" and "sinus tract type" probings, another clue for diagnosis is a non-vital (necrosed) pulp

- these two lesions can completely heal after root canal treatment.

Acute or blow-out lesions: a tooth with this type oflesion will show normal sulcus depth allthe way around the tooth until the area ofthe swelling is probed. At this point, the probe dropssuddenly, to a level near the apex. The probing depths in all other areas are within normal lim-rts.

Periodontal lesions characteristically show bone loss which begins at the crestal bone leveland progresses apically. Hence probing defect would be conical in shape. This type of lesionmay not be amenable to root canal treatment alone even if it is associated with a pulpless tooth.However, endodontic treatment must be completed prior to tackling the periodontal problem.

A narrow sinus tract type lesion: the probing reveals nomra) depths al) around the tooth ex-cept at one very narrow area. Here, the probe can pass down the root surface to some distanceand sometimes even to the apex. The tooth is pulpless (non-itel.). Once the root canal treat-ment is completed, the lesion heals within one week. i'r"ote; All sinus tracts should be tracedrvith a gutta-percha point by radiograph.

Remember: A perio-endo abscess is a combined lesion. The lesion usually demonstrutes ra-dioeraphic involvement ofthe periodontium and the apex ofthe involved tooth.

Important: To distinguish a periodontal lesion lrom an endodontic lesion, pulp vitality tests

alLrng $ ith periodontal probing are essential.

\ote: A common clinical finding ofa periodontal problem is pain to lateral percussion on atooth rrith a wide sulcular Docket.

*** Thesc may actually increase the chance offracture. The parallel-sided posts are prefened.

Options availablc whcn restoring endodontically treated posterior teeth:

. R€storation ofocclusal opening only: in rare instances thc access opcning and ca es destnrctiondo not encroach on the cusps and marginal ridges. These teeth may be restored with an occlusal amal-garr; however, a cuspal coverage restoration would provide protection from fracture.

. Onlay restoration: in most cases it is imperative that root canal treated t€eth b€ protected fromfracture by a cusp-coverage qpe ofrcstoration. The minimum (ra ost conserwtiv) preparation should

be for an onlay' covering the cusps and marginal ridges.

. Cro$n: a full-coveragc crorvn is prcfcrred whcn the rcmaining coronal tooth strucrurc does not af-ford sull'icicnt tooth structure for an onlay.

. Cro$n $ith post and core: to reinforce the treated tooth and provide suitable coronal tooth strxc-mre for an optimum crown prcparation, thc usc of a post and corc is often indicared. Be very careful$ hen placing posts. Perforations and vertical root fractures can occur. Important: The primarypurpose ol the post is to rctain a corc in a tooth whcn thcrc is an cxtcnsivc loss ofcoronal tooth struc-

rure Posrs do not reinforce the tooth, but further weaken it. At least 4 to 5 mm ofremaining guna-per-

cha is recomnended.

1. Ifyou arc performing a pulp chamber-retained amalgam, you need to placc amalgam 3

\otes mm inro each canal for retention.

.., l. Endodontically trcatcd postcrior tccth arc morc pronc to fracturc than Llntreated postedor_i::!_': teeth due mainly to the destruction ofthe coronal tooth structure

-they have reduced struc-

tural integrity.3. More endodontically treated teeth are lost because ofrestorative factors than failure oftheroot canal treatment itsclf.4. Pemanent restorations arc bcst placcd ASAP after obturation to seal the intemal aspeot

of thc tooth from contamination.5. Endodontically heated teeth do not become brittle. The moisture content ofcndodonti-cally treated teeth is not reduced even after l0 years. Key pointi Tccth are weakened by thcloss of tooth structure.

Misc.

Retreating a tooth with a post is the most common reason for anapicoectomy and retrograde filling,

Whenever a reverse lilling procedure is to be used, apicoectomy is mandatory toprovide a table into which the preparation and filling will be placed.

. The first statement is true, the second is false

. The first statement is false, the second is true

. Bolh statements are true

. Both statements are false

40

CopFight C 20ll'2012 - Denral Decks

ENDODONTICS Misc.

Endodontic procedures involve taking multiple radiographs. How should

)ou protect yourself or your staffwhile taking radiographs if there isno barrler available to stand behind?

. Stand at least 4 feet away anywhere around the patient

. Stand at least 5 feet away exactly opposite the x-ray bearn source

. Stand at least 6 feet away and in the area that lies between 90 to 135 degrees to x-rayDeam

. Stand at least 7 feet away and in the area that lies between 60 to 90 degrees to x-raybeam

. Never take an x-ray without a barner

41

copyright () 2011-l0l: - Denrll Decls

An apicoectomy is thc prcparatior ofa llat surfacc by thc cxcision ofthc apical portion ofthc root and any subsc-qucnt rcmoval ofattached soft tissucs.

Ifa toolh has had previorrs endodonlic lherapy and becomes reinfectcd, il is usually bcst lo try and .etreat it con'vcntionally remove filling marerial, debride the canals, and rcfill. However, iltbe tooth has bccn restorcd $ith a

post, corc. and crown thcn apical curcttagc, apicocctomy, and a rclrotill should bc pcrformcd. Note: Rctrcaling a

tooth with a post is the most common rerson for an apicoectomy and retrograde fllling.

Indications for apicoecaomy (root-e n d rc se c tion ) |

. A rcvcrsc filling nccds to bc placcd

. ll is ncccssary to gain acccss to an area ofpathosis

. Thc poorly fillcd apical ponion oflhc root is to be rcmoved to the levcl ofcanal obliteration

. Non-ncgotiablc canal, blockagc or scvcrc root curvaturc in wbich non-surgical trcatrnc t is impossiblc

. Complications arising fiom proccdumi accidcnts (e.9., separat ion of instrumentt, ledsingai /or pertrrruliot$)$hich cannot bc handlcd withoul surgical cxposurc ofthe sitc. Failcd rcatmcnt duc to inetricvablc posts or root fillings. Horizontal apical liacturcs in which apical cnd ofthc pulp bccomcs necrotic. Biopsy . to diagnosc non-odontogcnic causcs of symptoms &.9., p.rlient *ilh a histotr 4 pre|ious nalig-nancr, Iip paresthesid or anesthpsia)

Contrsindications for api.oectomy (rcol-end rcsection):. Anatomic factors that limit acccss . Mcdical or systcmic complications . Toolh is nonrcstorablc or has a poorcrown/root ratlo

Procedure:. Radiographs are taken to determine the length ofthe root and ils proximity to adjacent structurcs. Administer anesthesia. On th€ labial surfacc ofthe tooth, witb the help ofa pcriostcal elcvator. locatc the root apex, so that an incisioncan bc madc. Flap designs used: submarginal scallopcd fO. ltsenbein- l,uehke) ,

^nd t! I I m ucoperiosteal flaps t ? r"Jr/

. Reflect the flap

. Root apex is exposed, thcn apcx is cut olf with a lissure bur about one-third of its lcngth

. Curette the surrounding pathologic tissucs and round ollthc end of thc cut rool

. For retrograde filling, a bevel of0-10 dcgrccs is grvcn

. Retrograde filling to I mm is donc

. Irrigate the wound Nnd ruture the llap in position

Notes rclated to radiation safety and diagnostic radiographs:1 . A fast (se sitive) filfir, lor example E-speed (Ektaspeed or Ektaspeed phts) film is preferredo|cr D ltlm (Ultraspee.l) as laster films require less radiation faboal /rallJ exposure while pro-viding quality image. r-ote: A newer F-spced. (Insigh, filrnhas been recently introduced that re-quires 20% to 25% lcss cxposure than E-speed film but more studies need to be donc to accesslhe usefulness ofthis new filrn typel. Dental units should operate at 70kV or higher. The higher the kV, the lower the patient's skindoses. \ote: The optimal setting formaximal contrast between radiopaque and radioluccnt struc-turcs is 70 kV.L Collimation fi.e., restfiction ofthe x-rq) beam size so that iL does not exceed 2.5 inches at thepurient! skin, reduces exposure).J. Patient should be protectcd with a lead apron and a thyroid collar for each exposure.5. If there is no barrier for thc clinician to stand behind while exposing films, hc/shcshould stand in an area of minimal scatter r^diztiorr ( i.e., 6.feet otrat and i the area thot liesb, n'een 9(P to 135" to x-ray beam)6. DeIltal personnel who may gct exposed to occupational x-radiation must wear fiLn badgesto record exposurc and must never exceed the maximum permissible dose IMPD) of50 mSv peryear/whole body.7. An operator should never remain in the room holding an x-ray packet in place for a patient.lffilm must be held in place by somcone else (i.e.,lor a child.1, drape the patient and have him,/herhold the film.8. The most accurate radiographs for endodontics are made using the paralleling technique.Remember: When using the paralleling technique, you must ccntcr the X-ray film packetbehind, and parallel with the long axis ofthe tooth bcing X-rayed. The tube head must be posi-tioned so that the ccntral X-ray beam is projected perpendicular to the tooth and the lilmPacket.

. Porphyromonas species and Bacteroides melaninogenica

. Eubacterium and Fusobacterium

. Actinomycetes and Spirochetes

. Wolinella and Veillonella species

12copyrighr O 201l-2012 - Detual Decks

the cemento-enamel junctionreYeals that probing depths are

. Extensive periodontal treatment followed by vitality re-assessment

. Endodontic treatment only

. Endodontic treatment followed by periodontic treatment

. Root end surgery

. Periodontic treatment followed by endodontic treatment

43copyrighr O 201 l-2012 - Dental Decks

Predominant bacterial species isolated from infected root canals include:. Porphyromonas species. Bacteroides melaninogenica. Eubacterium species. Peptostreptococcus species. Fusobacterium species. Prevotella species*** Note: Strict anearobes predominate

Virulence factors which play a role in periradicular pathosis include:. Lipopolysaccharide (LPS): found on the surface ofgram negative bacteria. Enzymes: neutralize antibodies and complenent components. Extracellular vesicles: involved in bacterial adhesion, proteolytic activities, hemag-glutination and hemolysis. Fatty acids: affect chemotaxis and phagocytosis

A vital pulp resists bacterial invasion. Even ifthe pulp is exposed to microorganisns for2 weeks, the penetration ofbacteria may extend no more than 2 mm into the pulp. In con-trast, a non-vital pulp is a fertile ground for the growth of microorganisms and leads tonecrosis.

Remember: Streptococcus species may be more important in the initiation ofrather thanthe progress of a carious lesion leading to a pulp exposure. Strict anaerobes are foundto play a significant role in periapical pathoses.

*** In a combined perio-endo lesion, endodontic treatment generally takes precedence

over periodontal management.

Combined endodontic-periodontal therapy is widely used because the anatomic andclinical connections between the pulp and periodontal structures are close and numerous.In most cases ofthis nature, endodontic procedures are preformed first and, when nec-essary, are followed by periodontal measures.

In these cases, the value ofprecise pocket probing and correct appraisal olthe vitalityof the pulp is crucial. In some doubtful cases, the better part of wisdom is to wait untilafter the completion ol the root canal therapy to see whether spontaneous resolutionlpocket closure and osseous ./ill-in) will occur before surgical periodontal procedures are

begun.

Periodontal therapy should be initiated first only in the case ofa primary periodontal le-sion rvith subsequent secondary endodontic involvement.

Remember: A common clinical finding ofa periodontal problem is pain to lateral per-cussion on a tooth with a wide sulcular pocket.

Note: The combination lesion (perio-endo) is dorninated by gram-negative anearobicbacteria

. Reticulin fibers

. Collagen fibers

. Unmyelinated nerve fibers

. Myelinated nerve fibers

. Proprioceptor nerve fibers

. Mantle dentin

. Circumpulpal dentin

. Predentin

. Secondary dentin

. Tertiary dentin

44

Coplright O 2011,2012 - Dmral Decls

45

Copfight O 201 1-2012 - Dfrlal Deck

: trote*:

*** Proprioceptors fwhich respond to stimuli regarding mot'ement, are not found in the pulp.

The pulp contains both myelinated and unmyelinated nerve fibers. They are afferent and sympathetic.The myelinated fibers are sensory and the unmyelinated fibers are motor

-they play a role in the reg-

ulation ofthe lumen size ofthe blood vessels.

Important: The only type ofnerve ending found in the pulp is the free nerve ending, which is a spe-cific rcceptor for pain. Regardless ofthe sourcc of stimulation fl,eat, cold, pressurc), the onl,v rerponsewill be pain.

Afferent N€rve Fibers found in the Dental Pulp:. Large myelinated A-delta tibers: enter at tl')e apical foramcn, follow thc path ofthe blood vessels,and then branch to form tl,c Plexus ofRaschkorv beneath the cell rich zone. Within thc plexus, thefibers lose their myclin shcath and proceed to the cell-free zone where they form a subodontoblasticplexus. The free ne e endings then pass into thc odontoblastic layer and the predentin. A-delta fiberpain is immediately pcrceived as a quick, shar?, momcntary pain that dissipatcs quickly on removalofthe stimulus. Note: The intimate association ofA-delta fibers with thc odontoblastic ccll layer anddentin is rcfcned to as thc pulpo-dentinal complex.. Small unmyelinated C fibers: enter at the apical foramen within thc A dclta fibcr bundlcs; distrib-uted throughout the pulp. They are associated with burning, aching, throbbing q?cs ofpain. Charac-terized by having a high threshold of stimulation. These fibers are true nociceptivefibers pain-conducting fibers that respond to stimuli capable of injuring tissuc. They rcmain cx-cilable even in necrotic tissue. Nole: These fibers are stimulated by hot liquids or foods.Important: When C fiber pain dominates, it significs irreversible local tissue damage.

i. As the pulp ages there is a decrease in rettc.ulin f$ers (the pulp becomes less cellular andmore fibrous).2. The sizc ofthe pulp also decreases because ofthe conrinued deposition ofdentin.3. As thc pulp ages thcrc is an increase in the number ofcollagen fibers and calcificationswithin the pulp (ca11ed denticles or pulp stones).4. Pulp stones are associated with chronic pulpal discasc - tiom advanccd carious Icsions orlarce restorations.

Immediately adjacent to the odontoblast layer in the pulp, l0-47 pm ofthe dentin matrixremain unmineralized. Ifthis unmineralized layer ofdentin is lost 1e.g., due to taLtmct orinfectious process) it predisposes the dentin to internal resorption by odontoclasts.

. Mantle dentin: is first-formed dentin which is laid before odontoblast layer gets

organized. Hence the pattern ofdeposition and size ofcollagen fibers is different fromcjrcumpulpal dentin.

. Circumpulpal dentin: represents most of the dentin which is formed.

. Secondary dentin lorms after eruption of a tooth and throughout life resulting in a

Sradual but asymmetric reduction in pulp size.

. Tertiary dentin or reparative dentin: is an irregular and disorganized layer ofdentinlaid dorvn in response to any injurious/irritant stimuli.

Note: Dentin lormation is the primary function ofpulp.

Other functions include:. Induction: forms dentin which in turn induces enamel formation. Nutrition: dentinal tubules are linked to the pulp which maintains its hydration and

formation of peritubular dentin

i .. .. l. Once bacteria enter the pulp with sufficient quantity or virulence, complete

,/Noq: pulpal necrosis is imminent and ireversible.?&i Z. Bacteria from dental caries are the main cause of more serious pulpal injury,

and the main cause ofpulpitis.

f :' .: The

,.,.,r,.. , uN.

. Collagen, pulpectomy

. Network ofcapillaries and nerves, pulpectomy

. Collagen, pulpotomy

. Network ofcapillaries and nerves, pulpotomy

. The permanent maxillary right first molar

. The permanent maxillary right second molar

. The permanent maxillary right third molar

. The permanent maxillary right first premolar

46

Coplright @ ?01 1,2012 - Denlal Deck

17

Coplright O 201 l-2012 - Dental Decks

Reprinred frm Bdh Balogh. Maryand Ma.garet J. F.hrcnbach.. D""talEnbdoloe;, Hislolog, and AnotonttSecond e.litionA 2006. wit\ pennis-sion frcm Elsevie. Saundes.

Mainly, Type I and Type III collagen is present in the pulp in a ratio of557o : 45%. TypeV is found in small amounts. In dentin, Type I collagen predominates. Odontoblasts syn-thesize Type I while fibroblasts in the pulp synthesize both Type I and Il.

The central zone or pulp proper contains large nerves and blood vessels. This area islined peripherally by a specialized odontogenic area which has three layers (from inner-most to outermosl).

l. Cell rich zone: innermost pulp layer which contain fibroblasts.2. Cell-free zone or zone of Weil: is rich in both capillaries and nerve networks. Thenerve plexus ofRaschkow is located here.3. Odontoblastic layer: outermost pulp Iayer rl,hich contains odonroblasts and liesnext to the Dredentin and mature dentin.

Cells found in the dental pulp include fibroblasts (the principal cell). odontoblasts, his-trocyles (mocrop haset, and lymphocytes.

Note: In a diseased pulp, the following cells are present: PMN's, plasma cells, basophils,eosinophils. lymphocltes, and m ast cells (contain histantine and heparin).

Important: The pulp lacks collateral circulation, which severely limits its ability tocopc rr ith bacteria. necrotic tissue. and inflammation.

jwi\A'A{twV

Wa0o

M]/(Fryl\ea2

$:rodl€t3l

Att Bllv

Pulp cayity of the permanent maxillaryrisht second molar

Pulp cavity of the permanent maxillaryrisht first molar

Retirlnred iion B.tl}B.lo8h, Mrrt and Margar.l J F.htcnb^cb Dolal Enh\ ol/4r, Hisloln$ .h,l ,lnd1o,tr 5..a,1.d/to, :o 2006- * lrh permi$ron liom Ekevier SaundeF

fr) 0v

. The permanent maxillary right first premolar

. The permanent maxillary right second premolar

. The permanent maxillary right first molar

. The permanent maxillary right third molar

Reprinted from B8rh-Balosh, M6ry and MaFgarei J. Fehrcnbach..Dental Enbryologr, Hn'toloEr, ahd Anolon,Second edition @ 2006.wnhpemission from EI-

. The permanent marillary right first premolar

. The permanent maxillary right canine

. The permanent maxillary right lateral incisor

. The permanent maxillary right second premolar

4E

coplright O20ll-2012 - Dental Decks

,t9

Cop]'isht O 201l-2012 - Dental Decks

Reprinted fron Bath-BdloSh, Mary ard Margaret J. febrenhch.DentalEnbryolog, Hktolog,, ond Arcto8r,Second etlition @ 2006.wiih pemission from El'

i secti(

&e.@ &e*&llaalodletal

Pulp cavity of the permanentmaxillarf- right first premolar

Csrvlealcroea aectlon

l*aalodblrlBrrccolingrrel

R::rl.'n]n.ttJl1jBiogh'v.rand\,argar.t.]F.h|!nbaclrDe,/rl/E,lna,l'9'}|i'kn.g'ant1:1hlltont|:St.r .. ..r :i.I FL.\re. SaLnder

/\

(rt\t\tl\yLoblollngual

aoclloB

A\1//

\il/\l

Meslodistalagcllon

A

@Lablollnguol

sectlon

Repnnred froD BadlRalogh. Vary and Nrargarel J. Fehrenbach D.hkn Fhbtlolo*: Hinnlo'at: tnJ lntbht) 5..ot1.tlitn'n a.r2006,*irhrm,$'on frenr tts!ier Srundes

Pulp cavity of the permanentmaxillary right canine

Pulp cavity of the p€rmanentmaxillary right second premolar

Cervtcalcrosa Secllon

Pulp cavif"v of the permanentmandibular right canine

Mesiodi3lalsectlon

. The permanent mandibular right third molar

. The permanent mandibular right second molar

. The permanent mandibular right second premolar

. The permanent mandibular right first molar

. The permanent mandibular right camne

. The permanent mandibular right lateral incisor

. The permanent mandibular right first premolar

. The permanent mandibular right second premolar

50

Cop,riSht O 201 l-2012 - De d Decks

51

CopFiehr O 201l-2012 - Dental Decks

Rep.inted from Bqth-Balogh,Mdry 6nd Ma€!rci J. Fcbren-beh.. Deabl Enht?ologr', Htt-tolos, and Analoity. Secon.l

"dtor @ 2006, with pemivsion frcm El*viq Sadd€ls.

R€?nnted from Bath-BaloehMary and Margarci J.

Fehc.beL. D.u ral t'rlr-olosr', Histolog, drdAndtoh!, Second edition @

2006. with pe.nission fiofr

ATWI\qf/\V'::lls*'

/-\a)tlj ty

/A-.)\/wrIWI\H/\[i

tuerollngual

W@

rn\Bi\H/\d)

/r-\l\ffi/\q H/

W

ArAtg] \-/

Atny\HIW

Euccollngurl

P-'?\tr--1/

\ffijuo3Lglrt l

F^r\\ @]lU=:

.A\t]I/\\l/

WL.slodlrt.l

Re|nntc.jti.n]B3th-B3L.8h.\larlndN1argarelJ,Fehrenbtc\'DentllEh1ht|.bg'HisbI.e\'a"1l.1hdant's..a"d..Lm i;.'r hr) llie\rersaunde^

C€rvical

Pulp caYirJ* of the permanentmandibular right first molar

Pulp cavity of the permanentmandibular right first premolar

Pulp cavity ofthe permanentmandibular right second molar

Pulp cavity of the permanentmandibular right second premolar

(three-cusp \'pe)

Rqrrint.d fron Brth-Brbgh, Mary and VargareiJ. Fchrcnbacn D.ntal l:nh\.artEr, H5lDlo.i, an,l A"atanr, S..an.l .drbh a,2006. {nh aJeFftrsno. lionr Ehevier Saunden

. The permanent maxillary right canme

. The permanent maxillary right first premolar

. The permanent maxillary right central incisor

. The permanent maxillary right second premolar

. The permanent maxillary right third molar

. The permanent maxillary right second molar

. The permanent maxillary right first premolar

. The permanent maxillary right first molar

52

copyrighr O 20ll-2012 - Dental De.ks

53

Coplrighr O 20ll-2012 - Dental D€cks

Reprinied frcn Bath-Baloeh. Mary and Margaret J. Fchenbach..Dertal EhbrloloAu l-lis-tologr', dad Arolon!, sec-

on.l e.lition A 2006, wnhp€mission fro'n Elsevier

A 4Nml A/ll\ @ /A\ 1r1 q fil\I A i\",.:T::xl"" tP/ \ltl ",*"Ir=J v \l tU

Meslodistal Lablollogual Moslodlstal Lablotinguslaoclion seciion iici6n- sectton

m\i\w/)\a,A(t 1\ tl)\| Iilv

@Svc.ollngt al

(I,lql0l

W'ffi.x'"'

/F^\t{ @)

@

.....|l:.::;.[I3]l1]t]]trah'\J!rmdV!rga'elJ.Fehrenblch'D.n|dlEh|h|v|ap'||^1o'r :. r -. r Fli.lre. SrLrdcrs

Pulp cavity of the permanentmarillary right central incisor

Pulp cavity ofthe permanentmaxillary right third molar

Pulp cavity of the permanentmandibular right central incisor

Pulp cavity of the permanentmandibular right third molar

Reprinted lionr Bath-Baloeh. Maryand Vargarel Jmbsio. fio'n Ehevier S.uide^

Fehrenbrcla D.,r"/ E r/,1,h lt, HtttolDir, d,d .1ad t.ntt, 5..,,a .drr., ! :006. $rh ncF

. The permanent maxillary right central incisor

. The permanent maxillary right lateral incisor

. The permanent maxillary right canme

. The permanent maxillary right first premolar

Rep.inred ft om Bath-Balogh.M.ry and M$garet J.

FehrcnbetL Dentot Enbd-ologl Histologj lnrlAnatory', Second edition <)

2006. with p€mission rroD

54

Cop)'right O 201l-2012 - Denral Decks

Copltighr O20ll-2012 - Dental D€cks

. \{ilk

. \later

. Saliva

. Saline

AItI\ili

Lablollngualsection

l.1l

lYrtil/\il1

\tMeslodlstql

s€ct,on

/l\

/u\

VLsblolingual

Ssctlon

t\\\lltttnlIil\

/&ib:JMesiodlstal

secllon

!:]l.::.::i.,J:BJd]BJl.gh'\hr]ndva.ea|.tJF.hrnbrchD.,l.lE'ln,r,14]r- .. r i.ri: Flr.lre. SaLnders

Csrvlcalcr0s9 Secllon

The pulp cavity of the permanentmaxillary right lateral incisor

Celvlcatcaoss secllon

The pulp cavitl of the permanentmandibular right lateral incisor

Important: Thc first priority oftrcatmcnt ofavulsion irturics is 1o prorecr thc viabilir)--. of thc pcriodontal ligamcnt.

Five factors thnt arc critical lo Ihc managcnrcnl oftraumatic avulsion injurics lo tccthl

L Timei thc time intcnal from injury ro rcplacemcnt ofrhc looth is a major lactor in rhc maintc|ancc of liga-mcnt \ irbility and subscqucDl rft)t rcsorption. Tccth rcplantcd \l ilhin l0 mimurcs have been rcportcd ro cxhibil vcrylittlc rcsorpiion, u hcrcas most oflhe tccth rcplantcd aficr 2 hours sho* a lot ofcxtcmat roor rcsorprion ,,r,r,(, r,Ih" nail uus? ol fui1uft 4 rcpla r?d teeth).L Storage mcdia: ii thc toolh cannot bc imm€diatcly rcplanlcd, thc prcpcr sloragc ofthc ioolh c?n favorablvinfluence thc viabilitv ofPDLcells. Milk is considcrcd bcst fbrlhis purposc bccausc ofils ncarn€utralpH /6 j-6 lr rnd osrrolality. conducilc ibr the sur,"jval otcclls. Othcr storagc mcdia.rre physiologic salinc and snliva.I -lboth

socket: should not bc dam.rgcd by curctlttgc or fbrccful rcplantarion. Replanl slowly $i1h slightd:!rta nr.sLrrc.l Splint stabilization: a splint that allo\rs drc physiologic movcment is placcd fbr a maximum of I \\,ccks /Z n-'l,.L/r.irxl.rr.Thistimcpcriodallowslbrthcinitialrcarrachnrcntofrhcpcriodontat tigamcnt ilbcrs.j Root surfacci should not bc sc.apcd. dricd. or manipulatcd with causlic chcmicals.

Imporianti. T.n drvs ro n\o *ccks rtlcr rcplartation. tbc roor canal is prcparcd (Lleunrd utkl rr.rp€././ and a catcium ht,dro\ide paste is placcd into rhc cdnals. This rastc rs replaced ev€rv three montbs for onc ycar. If after one tear, it appcars that rcsorption has rcvcrscd or stoppcd. a pcrmancnt gurta-pcrcha Ulling can bc

\ote: The abovc informalion changes *hcn a tooth has bccn oul of thc mouth for more than 2 hours --mainly the trcahcnt ofthc looth sockct and root surf-aces. Changcs rrc as follows:

. Ankvlosis and erternal root resorption x'ill probably resulr withln hvo vcars. Ank]lojis rcsuhing iiom rc-placcrrcnt would give a bcttcr prognosis than external resorption, which u ill lcad ro farture.. Root canal thcrapy is pcrlbrmed in irs cntircty prior to rcplantatjon. Thc looth is soaked in a 2.470 fluoride solution acidulat€d at pII 5.5lbr t0 minutcs or nrorc. Thc fluoridc \rislow the resorpli\c proccss.. Gentll curctte blood clot out ofthc alveolar sockc( and irrigate with saline. RcplaDt slo*4y wi(h slighl digital pressuru. Stabilizc wjlh splint for a maxin]um of2 wccks (7 b lA ddrs is irteal)

. Both the statement and the reason are correct and related

. Both the statement and the reason are correct but NOT related

. The statement is correct, but the reason is NOT

. The statement is NOT correct, but the re:rson is correct

. NEITHER the statement NOR the reason is correct

. Vaintenance ofa normal anterior dentition

. To relieve parental guilt

. To maintain child's self-esteem

. To maintain child's social acceptance

56

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Intentional replartation implies that a tooth requiring cndodontic therapy is purposcly removedftom its socket, son]e type ofcanal or apical preparation and/or filling is perfonned, and thc toothis returned to its original socket.

Indications lbr intentional replantation falso called replant vugery);. When routine endodontic therapy of a tooth is impractical or impossible. When an obstruction of a canal is prcscnt. such as a broken instrument or a calcification, andperiapical surgery is impractical (e.g-, a lower molar w'ith the mandibular canal in close pro*inin. When perforating internal or external resorption is present, yet surgery is impractical. When a previous lreatment has failed but nonsurgical treatment or surgery is impractical

Note: lntentional replantation should be considered only when there's no other alternative treat-ment to maintain a "strategic" tooth. Long term follow up is required to monitor for complicationsincluding periodontal defccts and ankylosis with replacemcnt rcsorption.

Other surgical endodontic procedurcs.. Bicuspidization: is a process in which a tooth is divided into mesial and distal halves withoutremoval ofany. Endodontic treatment is done and two separate crowns are fixed on both halves.It is perfomred on mandibular molars with furcation involvement. Better stability ofthe toothis achieved when their roots are divergent.. Hemisectioni is the division of a mandibular molar buccolingually into two single-rootedtceth: the defective root is extracted. Hemisection requircs root canal therapy on all rctainedroot sesments. Note: When possible, it is prefcrablc to complete the root canal trcatment andplace a pemranent restoration into the canai odlices prior to the hemisection.. Root amputation: ref'ers to the removal ofa rcot from any molar without sectioning throughthc crown. Root amputation requires root canal therapy on all retained root segments.. Surgical removal of the apical segment of a fractured root: performed on a tooth when a

root fractwe occurs in the apical portion and pulpal necrosis results. Note; The coronal looth seg-ment must be restomble and functional or else this procedure is worthless.

*** The question ofwhether to replant primary teeth has been a focus of debate and contro-versy in the dental literaturc. However, most dental textbooks uniformly recommend that pri-mary teeth not be replanted. Replantation ofa primary tooth is not recommended because ofthe potential danger to the permanent successor from sequels of trauma fe.&, infection, anlglosis, or damage dtrc to uqnipulqtion during procedure itselfl.

Proper management of an avulsed permanent tooth that has been replanted within twohours ofthe accident:

. Ten days to two weeks after replantation, the rcot canal is preparcd (cleaned qnd.\hqped)

and a calcium hydroxide paste is placed into the canals. This paste is r€placed every three months for one year. Ifafter one year, it appears that resorption has reversed or stopped, a permanent gutta-per-

cha filling can be placed

lmportant: Ifa tooth is out ofthe mouth for more than two hours:. Ank)"losis and external root resorption will probably result within two years. Ankylo-sis resulting from replacement would give a better prognosis than external resorption,u hich rvill lead to failure.. Root canal therapy is performed in its entirety prior to replantation.. The tooth is soaked in a 2.47o fluoride solution acidulated at pH 5.5 for 20 minutes ormore. The 0uoride will slow the resorptive process.. Gently curette blood clot out ofthe alveolar socket and irrigate with saline.. Rinse tooth with saline, replant into socket, and splint for a maximum of2 weeks.

Note: Resorption is the most frequent sequela to replantation. Three different types of re-sorption have been identified: surface, inllammatory and replacement (qnlg'lotic resorption).

Replacement resorption refers to resorption ofthe roat surface and its substitution by bone,resulting in ankylosis.

Internal resorption of a tooth is generally believed to be caused byinllammation due to an infscted coronal pulp.

. The first statement is true, the second is false

. The first statement is false, the second is true

. Both statements are true

. Both statements are false

58

CopFighr C 201 l-2012 - Dental Decks

. Surface resorption

. Infl ammatory resorption

. Replacement resorption

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lnternal (in;flammalory) resorption is usually asymptomatic and is discovered on routineradiographic evaluation. The anatomic configuration of the root canal is altered and in-creases in size with intemal resorplion. It will appear as an inegular radiolucency any-where along the canal space. The tooth involved may respond to pulp vitality tests. Whenintemal resorption is detected, a pulpectomy should be performed. Once the pulp tissueresponsible is removed, all resorption ceases. To "wait and see" may result in sufficientdestruction ofthe tooth to create a Derforation ofthe root.

Internal resorption of maxillaryright lateral incisor.

\ote: Although, intemal resorption can occur only when some of the pulp tissue is stilllital. a negative sensitivity test does not rule out this etiology. Also remember that some-times on a radiograph, an extemal resorptive lesion can superimpose the canal space tomimic intemal resorption. In such cases, another radiograph should be exposed at anangle to the tooth. The radiolucent lesion inside the canal space will not shift.

Bowl-shaped areas ofresorption involving cementum and dentin characterize external inllammatoryroot resorption. This type ofresorption is rapidly progressive and will continue iftreatment is not insti-tuted. Since both a necrotic pulp and the presence ofbacteda are necessary components ofinflammatoryrcsorption, the process can be arrested by jmmediate root canal beatment. The tooth is opened and thecanal is cleaned and shaped. A calcium hydroxide paste is placed in the canal. This is replaced everythree months for one year If after one year, it appears that the resorption has stopped, a permanent rootc nal filling (gutta-percia) can be placed. A calcium hydroxide-based root canal sealer is strongly rec-

ommended.

Surface resorption is caused by acute injury to the periodontal ligament and root sulface. It is verycommon, self-limiting, and reversible. Ifinjury is not repeated, healing takes place with new cementumand PDL. Root surface resorption is limited to cementum, may heal itself, and is not radiographically vis-ible.

Replacement resorption refers to resorption ofthe root surface and its substitution by bone, resultingin ankylosis. Replacement absorption accompanies dentoalveolar ankylosis due to extensive hauma tothe tooths aftachment

^ppafifis (peliodontal ligament damage).The tooth is often in infraocclusion due

to progressive submergence with growth. There is a metallic sound on percussion.

Rememberi This is often seen in unsuccessful replant cases.

Remember the etiology ofextemal and intemal resorption:. Erternaf resorption: periradicular inflammation, dental trauma (/erultihg in dafiage b attachhentapparatut), excessive orthodontic forces, impacted teeth, intemal bleaching ofnon-vital teeth.. Internal resorption: dental trauma (resulting in loss of vitalit)' and subsequent i fection), dentalcaries, pulp capping with calcium hydroxide, cracked tooth.

Note: Invasive cervical resorption is a clinical term used to describe a relatively uncommon, insidiousand often aggressive form ofextemal tooth resorption. Cha.acterized by its cervical location and inva-sive nature, this resorptive process leads to progressive and usually destructive loss oftooth structure.

Resorption of coronal dentin and enamel often creates a clinically obvious pinkish color in the toothcrown as highly vascular resorptive tissue becomes visible through thin residual enamel.

ImportantiThe majority ofmisdiagnoses ofresorptive defects are made between intemal root resorp-tions. cervical caries. and cervical resomtion.

. Lack of mobility

. Lack ofPDL on x-ray

. Pinl Appearance

. Infra-occlusion

. Apical scar

. Cementoma

. Traumatic bone cyst

. Globulomaxillary cyst

. Radicular cyst

. Cfuonic dental abscess

. Chronic periapical granuloma

60Copyright O 20ll-2012 - Dcnlal Decks

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*** Traditionally pink tooth has been considered pathognomonic ofinternal resorptionand is sometimes a feature ofcervical root resorption. lt is characterized by a pinkish ap-pearance of the tooth due to the grofih of granulation tissue undermining the coronaldentin.

Replacement resorption, which accompanies dentoalveolar ankylosis resulting from ex-tensive trauma to the attachment apparatus ofthe tooth is characterized by progressive re-placement ofthe root by the bone. Note: Histologically, it shows direct contact befweendentin and bone with no intervening PDL or cemental layer.

Remember: Replacement resorption's pathognomonic signs are:

1. Lack of mobility2. Metallic sound to percussion3. lnfra-occlusion of the involved tooth in the developing dentition

Important: Tooth mobility is directly proportional to the integrity of the attachmentapparatus or to the extent of inflammation of the PDL. Other causes oftooth mobility in-c Iude:

. Horizontal root fracture

. Recent trauma

. Bruxism

. Ovezealous orthodontic treatment

An apical scar is represcntcd by a periapical granuloma. cyst, or abscess that heals with scar tissuc.Well-circumscribed radiolucency resembling a granuloma. Tooth is non-vital.A radicular cyst usually occurs in a pre-cxisting granuloma. Scldom is painful. Radiolucency at apcxofnon-vital tooth.

A chronic dental abscess is often a result of a periapical granuloma. Radiolucent area at apex ofnon-Iital tooth. Fistula is often found leading from an abscess caviry Once drainage is establishcd, thc toothstops being painful. Note: A chronic periapical abscess is often the cause of a sinus tract in the gingi-ral trssucs of childrcn.

-\ chronic periapical granuloma is the most common sequelae ofpulpitis. It is asymptomatic and as-

iLrcialed wiih a non-vital tooth.

.\ cementoma occurs most frequently in the ant€rior region ofthe mandible. It starts as a radiolucentleritrn and then calcifies. The cementoma does not affect pulp vitality. Also called periapical cemen-tal dlsplasia.

.q, traumatic bone cyst is not a truc cyst sincc thcrc is no epithclial lining. Found mostly in young pco-ple. asymptomatic. Radiolucency which appears to scallop around the roots ofteeth. Teeth are usuallv\itel.A gfobulomaxillary cyst (developmental cys, is found at the junction of the globular and maxillaryprocesscs ofthc maxilla, between thc lateral incisor and the canine roots. Teeth are vital.

Alateral periodontal cyst occurs on a lateral periodontal location and it is ofdcvclopmental origin aris-ing fiom cystic degeneration ofclear cells ofthe dental lamina. Tooth is vital.An ameloblastoma is a benign, locally aggressive tumor arising from the odontogenic ectodem.Lesionsoccur as multilocular radiolucencics and frequently cause extensive root resorption. Thc mandible is af-fected four times more frequently than the maxilla.

A cementoblastoma is an odontogenic tumor characterized by the proliferation offunctional cemen-toblasts that folm a large mass ofcemennrm or cementum-like tissue on the tooth root.

. Radiopaque

. Easy to manipulate

. Hydrophilic

. Biocompatible

. Not toxic

. Short setting time

. Induction ofhard tissue formation

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coplri8ht o 20ll-2012 - Dental Decks

. A dull thobbing pain on masticatlon

. Sensitivity to hot, and/or cold stimuli

. A persistent feeling ofdiscomfort

. Vild bleeding

. Pail on percussion

Coplrigh O 20ll-2012 - Dental Decks

The main ions found in MTA are calcium and phosphorus. MTA has a high pH so it induceshard tissue formation. MTA has superior sealing ability and is not adversely affected by bioodcontaminants. [t also causes only low levels of inflammation because it forms fibrous con-nective tissue and cementum when in contact with the pe odontium. Note: MTA is difficultto manipulate and has a long settilg time. Despite these disadvantages, it's the material ofchoice today.

A retrofif ling falso called a reverse f lling or retrograde qmalgam.filling) rs placed to seal theapical portion ofthe root canal. This procedure is used when an apicoectomv alone will notyield a good result. Whenever there is any chance whatsoever that an apical seal may befaulty, a reverse filling material must be placed. For example, if the root canal appears cal-cified. it would be impossible to obturate most ofthe canal and get a seal. Ifjust the root apexwere cut off faplcoectoatl, the incompletely filled canal might act as a source ofreinfection.To prevent this after the root tip is resected, the foramen is found, enlarged, and filled with a

zinc-ftee amalgam to create a seal.

An apicoectomy lro ot-end rcsection) is a procedure where the buccal tissue is flapped back,the buccal bone about the apex is removed, the root apex is removed, and the area is curet-ted out. Indications for apicoectomy: l) A reverse filling needs to be placed 2) It is neces-sar] ro gain access to an area ofpathosis 3) The poorly filled apical portion ofthe root is tobe removed to the level ofcanal obliteration. Note: A retrograde amalgam hlling should al-$ a1s be done after an apicoectomy. Teeth that have posts in them and need to be retreated arerhe most common reason for an apicoectomy and a retrograde filling.Remember: Periapical curettage is the same procedure as an apicoectomy (as far os fap andremotal ofbuccal hor€) but without removing the root apex. Removal and examination ofthediseased tissue and determination ofthe extent ofthe lesion are the objectives ofapical curet-Iace.

*** Thermal sensitivity is thc earliest and most common symptom ofan inflamcd pulp.

As caries entcrs thc dcntin it bcgins with a lateral sprcad al thc DEJ. This is duc 1o thc incrcascd orSanic conlcnt andthe involvcmcnt ofmany dcntinal tubulcs. Thc Tomcs fibcrs rcact, causirg fa(y dcgencnttion, thcn latcr dccalcifica-tion /.!.'/.,forrt. As caries progrcsses. destruction ofdentin is followcd by rhc bactcrial invasion ofrhe hrbules and complclc destruction ofdcntin. Once odontoblasts arc involvcd, pulpal changcs occur. Initially thcrc is vascrlar dilationand local cdcma. Tlc carliesa common slmptom ofthis edema fz./rreprlrth.) is thcrmrl sensitivity (us ullr it1-

o?used and persistent puin on upplirution oJ rcld).

Rememberr Thc only rcliablc clinical cvidcncc thal sccondary dcntin has formcd is decreased tooth sensitivitl_tuvnllr seen a lev vteel.s dlter place e t oIa li ing. whcn dcntinal tubulcs bccomc complctcly calcifrcd. thc dcntinis ins.nsitivc

L Thcrmal tcsts arc cspccially valuablcwhcn thc paticnt dcsc.ibcs fic pain as dillusc. Thc cold test can

\trtes bc Lionc w irh cold r s ter bal h s, sticks of icc, €thyl ch loridc, dich lorod ifluo rcnerharc / DDM , Eh.lo k e )

:. Thc heat test can bc donc wilh wann slicks oflutla pcrcha, using a rubbcr whecl mountcd on a man-drcl revolving at a polishing speed io gcncratc hcat, or a hot rvatcr bath.3. Thc bcst mclhod to clicit a most sccurute thcrmal rcsponsc is to individually isolatc thc suspcctcdtccth \r'ith a rubbcr dam and thcn balhc cach toolh in hol or cold water This is donc bccausc all othermcthods mav stinulate the iooth at only onc scction ofonc surfacc.

ResDonses to thermal tests:. \o response: indicates a nonvital pulp or a false negative responsc. Mild-fo-mode.ate response: slight pain that subsides within I to 2 scconds; }1ithin nor-mal limits. Strong, momentaay painful response: subsidcs within I to 2 scconds; indicates reversiblepulpitis. Moderate-to-strong painful response: lingers for scvcral scconds or longer; indicalcs ir-reversible pulpitis

,1. Thermal tcsls may be falsc-ncgativc in immature, recently traumatized lccth or bccausc ofpre-mcdicstion with an analgcsic.5. Although the percussion test docs not indicatc thc hcalth oflhe pulp, thc scnsitivity ofthc proprio-ccptivc tlbcrs does reveal inflammation ofthe apical PDL.6. A positive response to pcrcussion indicatcs not only thc prcscncc of inflammation ofthc PDL. bu!also thc cxlcnt ofthc inflamrratorv Droccss.

. An acute apical periodontitis

. A suppurative apical periodontitis

. An asymptomatic periapical granuloma

. An acute exacerbation ofa chronic apical periodontitis

. A chronic state ofan acute apical periodontitis

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. CAA is asymptomatic

' CAA is s;.rnPtomatic

. Only histological examination can differentiate

. The border ofthe radiolucent lesion

65Cop)'righr @ 201| -2012 - Denial Dcks

A phoenix abscess is also known as a recrudescent abscess. lt develops as the granulo-matous zone becomes contaminated or infected by elements from the root canal. Diagnosisis based on the acute symptoms fparn /o perc'ussion) plus radiographic examination, whichreveals a large periapical radiolucency. Note: A phoenix abscess is always preceded bychronic apical periodontitis. Signs and symptoms are identical to those of an acute peri-radicular abscess, but a radiograph will show a periapical radiolucency that indicates thepresence ofa chronic disease. Not€: The term "Phoenix Abscess" is becoming obsolete.The term replacing it seems to be "an acute exacerbation ofchronic apical periodontitis"(yes, the delinition is no\r the term).

A granuloma is defined as a growth of granulomatous tissue continuous with the periodontal ligament resulting from pulpal death with diffusion oftoxic products into the pe-riapical area. ln most cases a granuloma is symptomless. Radiographically, one sees awell-defined area ofrarefaction with some inegularities, while clinically the tooth is notsensitive. A massive invasion of pulpal contaminants will result in the formation of an

acute abscess (Phoenix abscess).

A cl st is an inflammatory response of the periapex, which develops from preexistinggranulomatous tissue (granuloma). It is characterized by a central, fluid-filled, ep-ithelium-lined cavity, surrounded by granulomatous tissue and peripheral fibrous en-capsulation. It is often associated with a chronically infected tooth. The tooth may bemobile. On radiographs. one will see a well-defined area of rarefaction (radiolucency)ivhich is limited by a continuous radiopaque, sclerotic border olbone. It is usually asymp-tomatic.

Important: A granuloma or a cyst can only be diff€rentially diagnosed by histologicaleramination.

The chronic apical abscess (also calletl suppuralire apical periodonltlr,/ is somctimes so painlcss that it nraygo undetected for years until revealed by an x-ray. It is a long-standing, low-grade infection ofthe periapicalbone with the root canal b€ing the source ofthe inf'ection. This condition may follow an acule alveolar abscess

or unsatisfactory root canal lherapy. Radiographs will reveal a diffusc radiolucency and PDL thickening. Thetooth may be slighlly loose or tender to percussion. The chronic absccss may be differentitted fiom cysts andgranulomas by the tact thatboth cysts andgranulomas have 1,ell'defincd radiolucencics associated with them.

The trertment is conventional root crnrl treatment.R€member: 309/o ro 5070 ofbone calcium must bc altered before radiographic evidence ofperiapical break-

do\rn occurs flrls .r//e/dtion takes place at tlrc junction beireen the cortical dnd cancellous hone).

The acute apical abscess (AAA) is a localized collection ofpus in the rlveolar bone at the root apex follow-ing death ofthe pulp $ith extension ofthe infection into ihc pcriapical tissue. The first symptom may be a slighttendemess ofthe tooth. This later develops into a severe throbbing pain to percussion rdth swelling oftheo|erhing mucosa. The tooth becomes more painful, elongalcd and loose. At timcs thc pain may dccrcase ordisappcar complctcly. Thc paticnt may appcar wcakcned. irritable and present with a fever. Thc dirgnosis is

bascd on lhe history. exam, and radiogmphs. The tooth \\,ill not r€spond to the EPT or cold test but may re-spond to heal The best treatm€nt ofan acute alveolar abscess includes establishing drainage and debrid-ing the canal s\ stem ofnecrotic fissue which will relieve the acute sy:nptoms. This is followed at a later dateb\ con\ entional root canal therapy.\ote: Ifthe abscess rupores through the periosteum into thc soli tissue, the

lrtic.fs svmproms *,ill subsidc.

lncision and drainag€ of solt tissues in indicated;.lfa plthway is needed in soft tissues with localized fluctuant swelling that can provide necessary drainage.\ote: It should be emphasized that, rhenever possible, lhe acute periapical abscess should be incised anddrained through the root canal system.. When pain is caused by thc accunrulatjon ofexudat€ in tissues.. wren it is necessary to obtain a cultr:re ofthc cxudatc

Apical trep hin ation is accorr pl ished by aggress ively p lacing a No. I 5 to 2 5 K-fi lc bcyond the confincs of theapex. Surgical trephination is a perforation of thc alveolar cortical bone to release accumulatcd tissue exu-dates. A small /J-lr/r/ horizontal inc ision is made with a No- I 5 scapel bl ade at ihe I e! el sl ightly apical to theroot apex. ANo. 6 or 8 round bur is uscd on a stmight handpiece to penetrate the conical plate above the rootapex. Iftherc is diffusc swclling f.e11 /irrt, antibiotics are usually indicated.

. Eventually the acute nature ofthe lesion will progress into a chronic, and non-painfullesion

. This lesion can progress into the bone causing osteomyelitis, a more severe condition

. The apical lesion has been there for years and the tooth needs treatment immediately

55Coprighl C201l-2012 - De alDecks

. EPT

. Cold test

. Heat test

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Osteomyelitis is not a particularly common disease. It is a serious sequela of periapi-cal infection that often results in a diffuse spread of infection throughout the medullaryspaces, with subsequent necrosis ofa variable amount ofbone.

Acute or subacute osteomyelitis may involve either the maxilla or the mandible. In themaxilla, the disease usually remains fairly wellJocalized to the area of initial infection.In the mandible, bone involvement tends to be more diffuse and widespread.

Clinically, the person afllicted with acute osteomyelitis is usually in rather severe painand manifests an elevation of temperature with regional lymphadenopathy. The teeth inthe area of involvement are loose and sore so that eating is difficult, if not irnpossible.Note: Another clinical symptom ofacute osteomyelitis is leukocytosis, an elevated num-ber of white cells in the blood.

Radiographically, acute osteomyelitis progresses rapidly and demonstrates little radi-ographic evidence of its presence until the disease has developed for at least one to twou eeks. At that time, diffuse lytic changes in the bone begin to appear Note: A "moth-eaten" radiolucent aooearance is evident.

The general principles of treatment demand that drainage be established and main-tained and that the infection be fteated with antibiotics to prevent further spread and com-plications.

*** The tooth will not respond to the EPT or cold tests but may respond to heat

Ofall the denral abscesses. the periapical is the most common t?e. It is a localized colleclion ofpus in thcalveolar bone at the root apex following death ofthe pulp with extension ofthe infection into the periapicaltissue. The first symptom may be a slight tendemess ofth(r tooth. This later develops into a severe throbbingpair. (ac te abscess) with swelling ofthe overlying mucosa. Reducing thc irrilant, reduction ofprcssurc. orthc removal ofthe inflamed pulp is the immediate goal. Ofthese, pressure relcase is the most effective in re-lie\ ing the patient's pain. Emergency treatment includes establishingdqinage (ideall! throlryh the cana[)and prescribing antibiotics lonlv il indicated hv s)'stemic signs dnd elewted tenlrera ture ) and ni alges ics. This!\ ill relie\ e ihe acute symptoms followed by conventional endodonric thcrapy at a latcr datc. Note: Completecleaning and shaping ofthe root canals is the preferred treatment. Horvever, iffor some reason this is not pos-

:ible. a pulporomv is usually effective in the absence ofpcrcussion sensitivity.

Important:\\hen diffuse swelling exists, the swelling has disscctcd into fascial spaccs. The most importantobjecti\ e is the removal ofthe irritant via canal debridement or extraction ofthe offcnding tooth. Swclling maybe incised and drained followed by drain insenion and systcmic antibiotics.

\ote: For endodontic infections that do not respond to penicillin VK, clindamycin is olien recommended. Itproduces high blood levels and is eflective against anaerobic bacteria but must be used with caution bccauseof the polenlral for p.cudomembranou. colrtis.

- l. A history ofpre-opcrative pain and s*'eiling is the best predictor of interappointment cmcr-

:Nol3*' gencres.

,- ' 2. No relationship exists between flare-ups and treatment procedures /i.e.. rirgle ormultiple|is-

3. The periodontal abscess is an acute abscess lhat devclops through thc periodontal pocket. Alve-olar bone loss, pocket formation and pe odontal pathologic conditions are suggestive ofthe peri-odontal abscess. The tooth \rill usually be palpation and percussion positive. lt will respond to theelectric pulp tester frrlike the periapical abscert. Bact€ria associated with this abscess includegftm-negative rods sucb as Capnocytophaga species, Vibrio-corroding organisms and Fusobac-lenum spccles,4. The gingival absc€ss is a relative rarity rhat occurs wh€n the bacteria iDvade through somebreak in th€ gingival surface. Such abrasions may be the result ofmastication, oral hygien€ pro-ccdurcs. or dcntal trcalmcnt.

. Reversible pulpitis

. Irreversible pulpitis

68

Cop}'ighr @ 20l l'2012' D€ntal Decks

r'\. . A seven year old boy arrives at the ollice with a complaint thrt tooth #8 is

draining pus into his mouth, The tooth had been traumrtized earlienThe vitality tesh reved no response. What is the treatment ofchoice?\')

. Extraction

. Apexogenesis / pulpotomy

. Root canal treatment

. Periodontal surgery to remove sinus tract

. It is only necessary to give the child analgesics and antibiotics for pain and infection

. Apexification

69

CoplriShr O 20ll-2012 - Dental D€cks

The severity ofthe clinical symptoms will vary as the inflammatory response increases. Pain $ ill vary liom a

mild and readily tolerated discomfort to a severe, throbbing and excruciating pain. The pain is spontaneous!unprovoked! and is int€rmittent or continuous in naturc. Thc pain lingers after the removal ofthe irritant.The pain is usually not readily localized by the patient but is difuse in character Lying down or bcnding overintensifies the pain ofineversible pulpitis because the overall increase in cephalic blood pressure is relayed tothc confined pulp tissue. The tooth may be tenderto percussion, heat may intensit the pain response while coldm y relieve it (in ad|anced s/dgerl. Usually they both will cause severe and lasring pain. Thc radiographs willusually disclose no periapical patholog!. Treatment is root canaltherapy. Note: In cases ofirrev€rsible pul-pitis, an acutcly inflamed pulp is symptomatic whercas a chronically inflnmed pulp is rs) mptomatic in most

cases. The end result is necrosis ofthe pulp.

. Asymptomatic irreversible pulpitis- possible consequences:

- Hyperplastic pulpitis: a rcddish, cauliflower-like growrh ofpulp tissue through and around a cariousexposure ofa grossly decayed tooth.-Internal resorptioni is a pathological process initiated *,ithin the pulp space uith the loss ofdentin. koften is described as an oval-shaped enlargement ofthe root canal space and usually is asymptomatic anddetectable by routine radioSraphs.

. Sr"mptomatic irrerersible pulpitis: as dcscribcd above, the pain is spontrneous, unprovoked! and is in-termitt€nt or continuous in nature- Pain will vary liom a mild and readily tolerared discomfoft to a severe,throbbing and excruciating pain.

Relersible pulpitis /h\'percniaI the pain associated with hlperemia does not occur spontaneously. I1 re-quires an extemal irritant to evoke a painful response /i.{,., .o/d. srt?ctr). Thc pains are sharp and ofbrief du-ration. ceasing \\'hen the irrilant is removed. Radiographs appear normtl lnat'shov,deep caries or catiq/,r1'l,1,"drirr. The tooth is usuirlly percussion negativc. In thcrmal tests. the pulp rcsponds more readily to colditrmuli fian to hot 1t € respo se laaws shortlv after rcnotal olthe stirrrlfur). Treatment usually is a seda-tire filling or nell restoration lvith a base.

Caus.\ ofrel ersible pulpitis inchde early carics, p€riodonl1l scaling, root planing. microleakage, and restora-

ronj placcd $ithout a base. Remember: Reversible pulpitis is not a diseasc, rather it is a symptom. Ifthe ir-ritanl ii removed, the pulp will revert to a healthy slatc. If the irritant rcmains, the symptoms may lead toirre|ersiblc pulpi!is.

\otei Pulpaf intlrmm^tion (h.r'perenia) is most commonly caused by bacteria.

Ap€xification is a technique whose goal is to induce further root development in a pulpless

tooth by stimulating the formation of a hard substance at the apex, so as to allow obturationofthe root canal space. Apexification may be rcquired afler pulpectomy as at seven years ofage the apex ofthis tooth must be open. Remember: Apex closes 2-3 years after emption.

The technique consists ofisolation ofthe field with a rubber dam, making an access cavity andremoving all pulpal tissue by the use ofreamers and files. A premixed syringe of a calciumhydroxide-methyfcellulose paste (/or erample, a Pulpdent s.vrlrge/ is injected into the canaluntil it is filled to the cervical level. The paste must reach the apical pofiion ofthe canal tostimulate the tissues to form a calcific barrier. A double seal ofcement is made to close offtheaccess cavity. The patient is recalled after three months to see ifapexification has taken place.

Ifnot. a liesh supply ofpaste is placed. lfapexification has occurred, conventional root canaltherapv is instituted.

The action of calcium hydroxide in promoting formation ofa hard substance at the apex is

best erplained by the fact that calcium hydroxide creates an alkaline environment that pro-rnoles hard tissue deposition. Note: Its high pH (pH-12.5) also causes an antibacterial ellectrnd it inacli\ ate: lipopolysacchande.

\ote: Ifa permanent tooth fractures and has a fully formed root and the pulp is exposerJ, (largeerpasure). the ffeatment of choice is complete root canal therapy. Apexification is notneeded because the root is fully fonned. lf the exposure is small and the length of time is

short ( I /2 hour to I hour), then a direct pulp cap with CaOH lbllowed by a restoration is theireatment (|fchoice.

Remember: Apexogenesis is the process of maintaining pulp vitality during pulp treatmentto allow continued development of the entire root. As opposed to apexification, this proce-

dure relates to teeth with retained viable pulp tissue in which this pulp tissue rs protected,

treated, or encounged to permit the process ofnormal root maturation.

. Transplanted teeth with partial root development have a better prognosis than thosewith developed roots

. Orthodontic extrusion is a common indication prior to implant placement

. Intentional replantation is a viable altemative to endodontic surgery

. A major disadvantage of endodontic implants is the lack ofan apical seal

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Coptaighr O 20ll-2012 - Dental D€cks

*** Intentional replantation is not a substitute for endodontic surgery if it can be un-dertaken.

Transplantation is the transfer ofa tooth from one alveolar socket to another either in thesame person or in another person.

Orthodontic extrusion is defined as force-controlled vertical tooth movement occlusallyin the socket. Indications include untreatable subgingival pathoses e.9., cervical caries, cer-vical fracture, periodontal defects, resorptive lesions and perforations in the cervicalatea.

Crown lengthening is a procedure used to apically position the gingival margin and./orto reduce the cervical bone. It is employed during the treatment of subgingival caries,perforations and resorption.

Root submersion involves resection of tooth roots 3 mm below the alveolar crest. Thecoronal portion ofthe tooth is removed and the roots are covered with a mucoperiostealflap. Indications include rampant caries, adverse periodontal conditions and in cases thathave had repeated prosthetic failures. The submerged roots will prevent alveolar resorp-tion and maintain better proprioception. This is especially useful in medically compro-mised or handicapped patients requiring better denture control- Sometimes, this is alsodone to avoid formation of an esthetic defect that may result after extraction.