Dentin Hypersensitivity DH102: Clinic II Lisa Mayo, RDH, BSDH Concorde Career College.

Dentin Hypersensitivity

DH102: Clinic IILisa Mayo, RDH, BSDH

Concorde Career College

Reference

Wilkins CH43

Outline

1. Define dentinal hypersensitivity2. Review Anatomy of Tooth Structures3. What can cause dentin exposure4. Hydrodynamic Theory5. Natural Desentization6. Desentization Products

Objective #1: Define Dentinal Hypersensitivity

Dentin Hypersensitivity

Short, sharp painful reaction that occurs when some areas of exposed dentin are subjected to certain stimuli: Mechanical Thermal Chemical

Hypersensitivity

Patient Concerns Hot/cold sensitivity to foods/drinks Pain during dental appointments: metal instruments

can elicit pain Will ask RDH why they have pain

Dentinal Hypersensitivity Difficult to diagnose: their pain could be caused by

many factors. May not be dentinal sensitivity. Numerous tx approaches Pain elicited by a stimulus and alleviated upon its

removal

Stimuli That Elicit Pain Reaction

Tactile or mechanical Toothbrushing Eating utensils Dental instruments Friction from prosthetic devises such as denture

clasps Evaporative

Dehydration of oral fluids as from high-volume suction or applying air to dry teeth during intraoral procedures

Thermal Cold more common than hot

Stimuli That Elicit Pain Reaction

Chemical Acids in foods and beverages such as citrus fruits,

condiments, spices, wine, and carbonated beverages Acids produced by acidogenic bacteria following

carbohydrate exposure Acids from gastric regurgitation Osmotic

Alteration of osmotic pressure in dentinal tubules due to isotonic solutions of sugar & salt

Characteristics of Pain from Hypersensitivity

Pain at onset Sharp, short, transient pain and rapid onset

Cessation From pain upon removal of stimulus

Chronic condition w/ acute episodesResponse to non-noxious stimulus (one that

would not normally cause pain or discomfort)Discomfort that cannot be ascribed by

another dental defect or pathology

Objective #2: Review Tooth Anatomy

Anatomy of Tooth Structures

Dentin Portion of the tooth covered by enamel on the

crown and cementum on the root Composed of fluid-filled dentinal tubules that

narrow and branch as they extend from the pulp to the dentinoenamel junction

The only portion of the dentinal tubules that are innervated with nerve fiber endings from the pulp chamber are those closest to the pulp

10% of all teeth have dentin exposure

Anatomy of Tooth Structures

Dentin Tubules in sensitive areas are wider and

more numerous Dentinal tubule closest to the pulp contains

an odontoblastic process: thin tail of cytoplasm from a cell in the tooth pulp called an odontoblast Fluid movement w/in open dentinal tubules

can stimulate certain nerve endings that are associated w/ the odontoblastic processes, resulting in a short, sharp pain in the tooth

Odontoblastic Process

DENTIN

PULP

DENTINENAMEL

Odontoblastic Process

Nerves

Anatomy of Tooth Structures

Pulp Highly innervated with nerve

cell fiber endings that extend just beyond the dentinopulpal interface of the dentinal tubules

Body portions of odontoblasts (dentin-producing cells) located adjacent to the pulp extend their processes from the dentinopulpal junction a short way into each dentinal tubule

Anatomy of Tooth Structures

Nerves Nerve fiber endings extend just beyond the

dentinopulpal junction and wind around the odontoblastic processes as shown in the next slide

Nerves react via the same neural depolarization mechanism (sodium potassium pump), which characterizes the response of any nerve to a stimulus

http://www.youtube.com/watch?v=HoJX6jZx7ss

Objective #3: What Can Cause Dentin Exposure

Mechanisms of Dentin Exposure

General considerations Once dentin exposed: demineralization of the root

surface will occur more rapidly than of the enamel Lower mineral content Higher critical pH to initiate demineralization

Acute hypersensitivity may occur with sudden dentin exposure since gradual exposure allows for the development of natural desensitization mechanisms such as smear layer or sclerosis

After many years, secondary & reparative dentin may have formed, which also protects the pulp

RECESSION

Factors Contributing to Gingival Recession & Root Exposure

Improper oral hygiene self-care Medium or hard toothbrushes Aggressive brushing Improper brushing motion

Anatomy and physiology of area Anatomically narrow zone of attached gingiva is more

susceptible to abrasion that can lead to recession and subsequent cemental exposure

Malocclusion Tight, short labial frena that pulls on gingival tissues

Subgingival instrumentation Large amts of sub-g calculus can pull gums away from

tooth and create recession May heal after removal

Frenum Pull

Factors Contributing to Gingival Recession and Root Exposure

Periodontal disease processes Junctional epithelium migrates apically in

response to inflammatory factors leading to connective tissue breakdown and loss of periodontal attachment

Surgical procedures Dr’s reduce pocket depths Gums repositioned Tooth extraction

Factors Contributing to Gingival Recession and Root Exposure

Orthodontic procedures & appliancesOral habits or piercings

Lip, tongue

Factors Contributing to Loss of Enamel & Cementum

Anatomy of cervical area Thin and easily abraded when exposed Enamel and cementum do not meet at CEJ in about 10% of teeth

Occlusion Constant trauma to teeth When recession present & pt grinds – can cause abfractions

Attrition and abrasion Mechanical wear Clenching / Grinding

Erosion Chemical wear of teeth From diet such as high acids, citric acids, wine, sodas Bulimics

EROSION

ATTRITION

ABFRACTION

http://www.youtube.com/watch?v=yeMrp1OHiBg&list=TLiKey6xaSc-mx7C8gTGYWtcmG7kG3C0o8

Objective #4: Hydrodynamic Theory

Hydrodynamic Theory

Currently accepted explanation for transmission of stimuli from the outer surface of the dentin to the pulp

Developed by Brannstrom (1960s): theorized that a stimulus at the outer aspect of dentin will cause fluid movement within the dentinal tubules Fluid movement creates a pressure on the

nerve endings within the tubule Transmits pain impulses by stimulating the

nerves in the pulp

Open Dentinal Tubules

Hydrodynamic Theory

Explains the following Dentinal tubules exposed Pain-producing stimuli are present Pain-producing stimuli initiate the flow of

lymphatic fluid within dental tubules Odontoblasts and their processes act as

receptors and transmitters of sensory stimuli Movement of tubular fluids causes nerve

endings in the pupal wall to be stimulated & produce pain

Objective #5: Natural Desentization

1. Sclerosis of dentin (your oral embry book p.101 refers to this as tertiary dentin, reactionary/response, reparative dentin)

2. Secondary Dentin3. Smear layer4. Calculus

Natural Desensitization

1. Sclerosis of dentin (tertiary dentin) Occurs by mineral deposition within tubules

as a result of traumatic stimuli, such as attrition or dental caries

Creates a thicker, highly mineralized layer of peritubular dentin (deposited within the periphery of the tubules)

Results in a smaller-diameter tubule that is less able to transmit stimuli through the dentinal fluid to the nerve fibers at the dentinopulpal interface

Natural Desensitization

2. Secondary Dentin Deposited gradually on the floor and roof of the pulp

chamber after teeth are fully developed Secreted more slowly than primary dentin that formed

prior to tooth eruption: both types created by odontoblast

Creates a “walling off” effect between the dentinal tubules and the pulp to insulate the pulp from dentin fluid disturbances caused by a stimulus such as dental caries

As aging occurs, secondary dentin accumulates, resulting in a smaller pulp chamber with fewer nerve endings and less sensitivity

Natural Desensitization

3. Smear layer Consists of organic and inorganic debris that

covers the dentinal surface and the tubule Accumulates following scaling and root

instrumentation, use of toothpaste (abrasive particles), cutting with a bur, attrition, or abrasion

Occludes the dentinal tubule orifices forming a “smear plug” or “bandage” that blocks stimuli

May have a positive or negative effect It protects from hypersensitivity, but may

interfere with reattachment of periodontal tissues

Natural Desensitization

4. Calculus Provides protective coating to shield exposed dentin

from stimuli Post debridement sensitivity can occur after removal

of heavy calculus deposits Dentinal tubules may become exposed as calculus is

removed

Patients and Their Pain

Dentinal Hypersensitivity Statistics Prevalence of hypersensitivity 8-30% of

adults Greatest age to be affected = 20-40yrs

Incidence decreases with increasing age = secondary dentin, sclerosis of dentin

Higher incidence in perio patients

Differential Diagnosis

Diagnostic techniques and tests Visual assessment of the tissues and teeth Palpitation both extra and intraoral Ask about sinus issues Occlusal exam: articulating paper Radiographic assessment: pulpal pathology? Vertical

root fracture? Percussion: use handle to tap on tooth to see if pain

elicited Mobility? Pain from biting: Bite Stick, cracked tooth Transillumination: cracked tooth Thermal/Electric tests on the pulp: Cold-Test

Question

After many years of root exposure, what structure can form that protects the root and pulp?

a. Primary dentinb. Secondary dentinc. Reparative dentin

Question

After many years of root exposure, what structure can form that protects the root and pulp?

a. Primary dentinb. Secondary dentinc. Reparative dentin

Objective: Desentization Products

Desensitizing Agents and Theorized Mode of Action: Mosby’s

Potassium salts Formulations containing potassium

chloride/nitrate/citrate/oxalate Reduce depolarization of the nerve cell membrane

and transmission of the nerve impulse by occluding dentinal tubules

OTCFluorides

Decrease the lumen diameter, block/occlude open dental tubules

Calcium phosphate technology Caries control to reduce demin and to remineralize by

releasing Ca, Phosphate ions for deposition of new tooth mineral (hydroxyapatite)

May occlude dentinal tubule openings

Desensitizing Agents and Theorized Mode of Action: Mosby’s

Oxalates Block open dental tubules Oxalate salts (potassium & ferric oxalate) decrease

the lumen diameterGlutaraldehyde

Can be combined with HEMA, a hydrophylic resin which seals tubules

Creates Ca-crystals w/in dentinal tubule to decrease the lumen diameter

Arginine and calcium carbonate Occlusal tubules using arginine (amino acid),

bicarbonate, Ca-carbonate Marketed as a px paste to be applied before

instrumentation

Types of Desentizing Tx

No single agent or form of tx is effective for all persons

Numerous agents have varying degrees of success Solutions, gels, pastes of fluoride in varying

compounds and % Adhesive, varnish, bonding materials Polymerizing agents

1. Glass ionomer cements (GIC)2. Adhesive resin primers3. Iontophorectic devises4. Laser therapy5. Restorations

Glass Ionomer Cements

Used in cervical abrasion and abfractionsSensitive area etched with 50% citric acidRinse with waterDryGlass ionomer placed

Adhesive Resin Primers

Reduce dentin permeability by occluding open tubules

Material rubbed on sensitive area for approximately 30 sec and air-dried

Iontophoretic Devises

Application of an electric current to impregnate tissues with ions from dissolved salts

Fluoride iontophoresis is thought to result in the increased uptake & penetration of fluoride ions into dentin

Devises are technique sensitive

Laser Therapy

One-time tx that reduces or eliminates dentin sensitivity

Seals tubulesSensitive dentin treated with laser is found to

be harder compared with untreated dentin

Restorations

Placed on surface where dentin is exposed to help reduce sensitivity

Unfilled or partially filled resins Covers patent dentinal tubules

Dentin-bonding agents Obturation of the tubule opening

Composite/glass ionomer

Soft Tissue Grafting

Surgical placement of soft tissue grafts can cover a sensitive dentinal surface

Results are somewhat unpredictable Done with a specialist High cost to patient

Behavioral Changes

Dietary modifications Limit acidic foods and beverages Evaluate use of dental products: no acid

formulations – can contribute to erosion Avoid hot/cold extremes in the mouth: no ice, coffee

not too hot…Excellent dental biofilm controlEval toothbrush type and techniqueEliminate parafunctional habits: mouthguard, ortho,

occlusal adjustmentsMedical referral for acid-reflux / GERD issues, Bulimia

suspectedAt home fluoride tx

FLUORIDE TRAY

Dental Professional Measures

Fluoride varnishes Does not require a dry tooth surface:

advantageous since this drying the tooth can be a painful procedure for a patient with dentin hypersensitivity

Novamin

Ca and Phosphate ions in ACP will seek out areas of demin and enhance enamel remin., occlude dentinal tubules, increase F uptake, prevent caries progression

High risk caries groups should usePeople w/ sensitivity should useShould be used in combo with FToothpaste, polish paste, sealant

Recaldent / Casein Phosphopeptides

Enhance the effects of Fluoride & provides a supersaturated environment of Ca and P for remin.

Not a Fluoride substituteHigh caries risk, sensitivity issuesCaries preventionGum, pastes, professional application

Additional Considerations

Tooth-whitening-induced sensitivity Commonly associated with carbamide peroxide A reversible pulpitis is caused from the dentin fluid

flow and pulpal contact of the material, which changes the osmolarity, without apparent harm to the pulp

Hypersensitivity = few days to several months Exposed dentin and pre-existing dentin

hypersensitivity increase risk for hypersensitivity secondary to whitening

Reduce tooth-whitening-induced sensitivity: Potassium nitrate, fluoride, or other desensitization product prior to & concurrently while whitening

Question

Novamin is made of which two ions:a. Calcium, phosphateb. Calcium, fluoridec. Phosphate, fluorided. Phosphate, Potassium

Question

Novamin is made of which two ions:a. Calcium, phosphateb. Calcium, fluoridec. Phosphate, fluorided. Phosphate, Potassium