ORTHODONTIC TREATMENT PLANNING : PROBLEM LIST TO SPECIFIC PLAN DR. ALI WAQAR HASAN FCPS – II RESIDENT IN ORTHODONTICS UCMD UOL
ORTHODONTIC TREATMENT PLANNING :
PROBLEM LIST TO SPECIFIC PLAN
DR. ALI WAQAR HASANFCPS – II RESIDENT IN ORTHODONTICS
UCMD UOL
TREATMENT PLANNING CONCEPTS & GOALS
Comprehensive list of patient’s problems = Orthodontic Diagnosis
Pathological & Developmental problems separated
Objective = To design a strategy using best clinical judgement to address the problems while maximizing benefit and minimizing cost & risk
Develop treatment plan in collaboration with patient
“Do not jump to conclusions” !!!!
MAJOR ISSUES IN PLANNING TREATMENT
PATIENT INPUT
Modern planning = Interactive process
Doctor cannot decide in a paternalistic way
Patients & Parents must be involved in decision making process
Ethically, patients have right to control
“Treatment is something done for them….Not to them”
Informed concent
DENTAL CROWDING : TO EXPAND or EXTRACT
Two controversial aspects of current orthodontic treatment planning
The extent to which Arch Expansion versus Extraction is indicated as solution for Crowding in Dental Arches
The extent to which Growth Modification versus Extraction for Camouflage or Orthognathic Surgery should be considered as solution for Skeletal Problems
From beginning of Specialty, Debate on Limits of Expansion of Dental Arches & advantages of Extraction of some Teeth to provide space for others outweigh the Disadvantages
With Extraction, Loss of Tooth/Teeth is Disadvantage
Greater Stability of result is an Advantage
Maybe Positive or Negative effects on Facial Esthetics
Contemporary View : Majority of Orthodontic Patients should be treated without removal of Teeth
Extraction to compensate for Crowding, Incisor Protrusion or Jaw Discrepancy
ESTHETIC CONSIDERATIONS
Major factors in Extraction Decisions = Stability & Esthetics
Expansion of arches moves the patient in direction of more prominent teeth, while extraction tends to reduce prominence
Prominence of Incisors = Excessive Lip separation at rest
Nose - Chin relationship
For Best Esthetics = Lower Lip should be as prominent as chin
STABILITY CONSIDERATIONS
For stable results how much arches have to be expanded ?
Lower arch is more constrained than the upper
Limitations for stable expansion maybe tighter than the upper
2mm Limitation for forward movement of Lower Incisors, as Lip pressure increases 2mm out into space
Incisors Tipped Lingually away from Lip can be moved farther than Upright Incisors
More opportunity to expand Transversely than Anteroposteriorly – but only distal to canines
Reports show that Expansion across the canines is never maintained, especially in Lower Arch
Intercanine Dimensions decrease with age = Lip Pressure at corner of Mouth
Expansion across Premolars & Molars is likely to be maintained = Low Cheek Pressures
One approach to Upper Arch Expansion is by Opening the Midpalatal Suture, if base is narrow !
Theory (with no supporting Evidence), upper arch expansion, creating Temporary Crossbite, Lower Arch follows Lead !!
Excessive Expansion carries Risk of Fenestration of Premolar & Molar Roots through the Alveolar Bone
Increased Risk of Fenestration = Beyond 3mm of Transverse Tooth movement
Soft Tissue Limitation
Fenestration of Alveolar Bone & Stripping of Gingiva
Amount of Attached Gingiva = Critical Variable
Pre-treatment with Periodontist
CONTEMPORARY EXTRACTION GUIDELINES
Contemporary orthodontic extraction guidelines in Class I Crowding
LESS THAN 4mm ARCH LENGTH DISCREPANCY:
Extraction rarely Indicated
Only if there is severe Incisor Protrusion
Severe Vertical Discrepancy
Some cases can be managed without Arch Expansion by slightly reducing width of selected Teeth
ARCH LENGTH DISCREPANCY 5 to 9 mm :
Non Extraction or Extraction Treatment possible
Decision depends on both Hard & Soft Tissue Characteristics
Any of several Teeth can be chosen for Extraction
Non Extraction Treatment = Transverse Expansion across Premolars & Molars
Additional Time if Posterior Teeth are to be moved Distally to increase Arch Length
ARCH LENGTH DISCREPANCY 10 mm OR more :
Extraction almost always required
Amount of Crowding equals the amount of Tooth Mass being Removed = No effect on Lip support & Facial Appearance
Extraction choice is Four 1st Premolars or Upper 1st Premolars & Mandibular Lateral Incisors
2nd Premolar or Molar Extraction rarely is satisfactory = No space near crowded Anterior Teeth or Options to correct Midline
Presence of Protrusion along with Crowding complicates the Extraction decision
Retracting the Incisors to reduce Lip Prominence requires Space within the Dental Arch
General Rule : Lips will move 2/3rd of distance that Incisors are retracted
Retrospective Studies of Ex vs Non Ex cases = Highly variable changes
The idea that Extraction will lead to narrow Arch and Incisor Retraction & that Non Extraction leads to Incisor Protrusion and Wider Arches is NOT WELL SUPPORTED
Final Set of Guidelines :
The more you can expand without moving Incisors forward = Satisfactory Treatment
The more you can Close Extraction spaces without over Retracting Incisors = Satisfactory Treatment
Oral Health = Excessive Expansion increases risk of Mucogingival problems
Masticatory Function = Expansion or Extraction makes no difference
SKELETAL PROBLEMS : GROWTH MODIFICATION vs CAMOUFLAGE
If it were possible, Best way to correct Jaw Discrepancy is to get the patient to grow out of it
Pattern of Facial Growth is established early in Life and it rarely changes
Important Q’s = Extent to which Growth can be Modified ? How advantageous it is to start treatment before Adolescence?
Data from Randomized Clinical Trials for Class II Treatment outcomes are available
Skeletal Problems in other Planes of Space remain Controversial
TRANSVERSE MAXILLARY DEFICIENCY
Close Relationship with Ex vs Non Ex decision
Child with Crowded teeth, a Diagnosis of Maxillary Deficiency can be a convenient Rationale for Transverse Expansion to align teeth
Width of Maxillary Premolar teeth and Width of Palate = Methods to Diagnose Maxillary Deficiency
Midpalatal Suture becomes more Tortous and Interdigitated with increasing Age
In a Child age 9, any Expansion Device (Lingual Arch), will separate the Midpalatal Suture, also move the molar teeth
Adolescence, Heavy force from a rigid Jackscrew Device used for separation (Microfracture
Maxilla opens like a Hinge superiorly, at base of Nose, also opens more Anteriorly than Posteriorly
Heavy forces and Rapid Expansion should not be used in school children = Risk of producing undesirable changes in nose at that age
After Adolescence = Bony spicule Interlocked Suture = Surgery
In Adolescents, Expansion across the Suture can be done in 3 ways :
I. RAPID EXPANSION with jackscrew attached to Posterior Maxillary Teeth, at rate of 0.5 to 1 mm/day
II. SLOW EXPANSION with same Device at rate of 1 mm per week
III. EXPANSION with a Device attached to Bone Screws or Implants
RAPID PALATAL EXPANSION Goal of Growth Modification = Maximize skeletal changes and Minimize the Dental Changes produced by
Treatment
THEORY : Rapid Force application to Posterior Teeth = Not enough Time for Tooth Movement = Force will be Transferred to Suture = Suture will open while Teeth move Minimally
RPE at rate of 0.5 to 1 mm/day
1 cm or more Expansion is obtained in 2 – 3 weeks
Most of movement being separation of two halves of Maxilla, Midline Diastema
Expansion device left in pace for 3 – 4 months for Stability
10 mm of Total Expansion = 8 mm of Skeletal Expansion & 2 mm of Dental Movement
After 4 Months ( 10 mm Total Expansion ) = 5 mm of Skeletal Expansion & 5 mm Tooth Movement
SLOW PALATAL EXPANSION
0.5 mm per week
1 quarter turn of screw ( 0.25 mm ) every other day
Ratio of Dental to Skeletal Expansion is 1:1
Large Midline Diastema never appears
10 mm of Expansion over 10 week period = 5 mm of Dental & 5 mm of Skeletal Expansion
Overall result of Rapid vs Slow Expansion is similar
With SPE a more Physiologic Response is obtained
CLASS II PROBLEMS In 1990’s two major projects using clinical randomized trial
methodology were carried out in University of North Carolina & University of Florida, both were supported by NIDCR
Data from Trials show 3 important things :
Children treated prior to Adolescence, had significant improvement in their Jaw Relationships
Changes in Skeletal Relationships created during early treatment could be reversed by Latter Compensatory Growth
At the end of comprehensive treatment during adolescence, no differences between early patients and previously untreated controls
CAMOUFLAGE BY TOOTH MOVEMENT
Tooth Movement alone cannot correct Skeletal Malocclusion
If malocclusion is corrected and Facial Appearance is acceptable then treatment outcome can be satisfactory, this is called ORTHODONTIC CAMOUFLAGE
Camouflage : Dental Occlusion + Facial Appearance
Camouflage means that Jaw Discrepancy is no longer apparent
Following 3 patterns of Tooth Movement can be used to correct Class II malocclusion
Combination of retraction of Upper teeth and forward movement of Lower Teeth, without Extractions
Retraction of Maxillary Incisors into a Premolar Extraction Space
Distal Movement of Maxillary Molars and eventually the Entire Upper Dental Arch
NON EXTRACTION TREATMENT WITH CLASS II ELASTICS
If Forward movement of Lower Arch can be accepted = Class II Malocclusion can corrected using Class II Elastics
Almost always, Class II patients have Lower teeth normally positioned on the mandible or Proclined to some extent
Result of Class II Elastics = Convex Profile with Protrusive Lower Incisors & Prominent Lower Lip ==RELAPSE WAITING TO OCCUR
After Treatment Lip Pressure moves Lower Incisors Lingually = Incisor Crowding
Return of Overjet and Overbite
RETRACTION OF UPPER INCISORS INTO PREMOLAR EXTRACTION SPACE
Straightforward way to correct Excessive Overjet = Retract Protruding Incisors in to Space created by Maxillary Premolar Extractions
Without Lower Extractions the patient would have a Class II molar relationship, but normal Overjet and Canine relationship at the End
Temporary Skeletal Anchorage
If Mandibular 1st or 2nd Premolars are also Extracted = Class II Elastics can be used to bring the Lower Molars Forward & Retract the upper Incisors, correcting both Molar relationship and Overjet
Class II Malocclusion due to Mandibular Deficiency ??
TMJ Dysfunction ?
DISTAL MOVEMENT OF UPPER TEETH
If Upper Molars moved Posteriorly = correct a Class II Molar Relationship and provide space into which other Maxillary Teeth could be Retracted
More Often Maxillary 1st Molars are Rotated Mesiolingually when a Class II Molar relationship exists
Tipping the crowns Distally to gain space is difficult, and Bodily Movement is Difficult Still
Until recently the Anchorage by Transpalatal Lingual Arch is accepted as the Best way to undertake Distalization
Can be done Theoretically with a HEAD GEAR = Time Consuming & Excellent patient compliance
Palatal Anchorage for Molar Movement can be created by Splinting the Maxillary Premolars & including an Acrylic Pad in splint so it contacts the Palatal Mucosa
2/3rd of space which opens between Molar & Premolars is from Distal movement of Molars
Tend to come forward again as rest of Maxillary Teeth are Retracted so more than a half – cusp Molar correction cannot be expected
Ideal Patient = Minimum Growth potential + Good Jaw Relationship
Temporary Skeletal Anchorage = Greatly improves Distal movement of Maxillary Dentition
Space in Tuberosity region = Remove 3rd Molars
Bone Anchors placed Bilaterally in base of Zygomatic Arch or in the Palate, Nickel Titanium spring generates force needed for Distalization
Bone Screws between Teeth prevent Distal Movement of Roots Mesial to the screw
In some patients = 6 mm of Distal Movement of 1st & 2nd Molars
In addition the Premolars move back along with Molars ( Due to SUPRACRESTAL FIBERS )
THE CAVEAT : (warning, Limitation)
If Class II Malocclusion is due to Maxillary Dental Protrusion, moving upper teeth back is logical approach
But if there is Mandibular Deficiency, Retraction of Maxillary Incisors after Distal movement of Molars & Premolars have same Potential Problem as that with 1st Premolar Extraction
SUMMARY
In the Absence of Favorable Growth, treating Class II is Difficult
Compromises have to be accepted in order to correct occlusion
Fortunately, even though Growth Modification cannot be expected to totally correct an Adolescent Class II problem
Some Forward Movement of Mandible relative to Maxilla does contribute to successful treatment
Rest of correction = Combination of Upper Incisor Retraction + Forward movement of lower arch
When No Growth expected = Orthognathic Surgery
CLASS III PROBLEMS
Growth Modification is just reverse of Class II
Differential growth of maxilla relative to Mandible
Edward Angle’s concept = Class III exclusively due to Excess Mandibular growth
Any combination of Maxillary deficiency or Mandibular Excess
Maxillary Deficiency frequent occurrence = Promotion of Maxillary growth
HORIZONTAL – VERTICAL MAXILLARY DEFICIENCY
If Headgear force = compressing Maxillary Sutures = Inhibition of Growth
Reverse Pull Headgear = separating the sutures = Stimulate Growth
Delaire & coworkers in France showed effects of reverse head gear
RESULTS = Successful Forward repositioning of Maxilla can be accomplished before age 8, afterwards the Orthodontic Tooth movement overwhelms the skeletal change
Even in young patients, 2 side effects are almost inevitable :
Forward movement of Maxillary Teeth relative to Maxilla
Downward & Backward Rotation of Mandible
IDEAL PATIENTS FOR THIS TREATMENT :
Normally positioned or Retrussive, but not Protrussive Maxillary Teeth
Normal or Short, but not Long, Anterior Facial Vertical Dimensions
MANDIBULAR EXCESS
Condylar Growth in response to Translation as surrounding Tissues grow
Results from CHIN CUP THERAPY are discouraging (Lower Incisors Tipped Lingually )
DeClerk : Light but Full Time force from Class III elastics is used from Skeletal Anchors in Maxilla to Skeletal Anchors in Mandible, effects on both the jaws are observed
CLASS III CAMOUFLAGE
Moderately Severe Class III = Proclining the Upper Incisors & Retracting the Lower Incisors into Extraction space
Unfortunately this illustrates as Camouflage Failure
Failure especially likely = Large & Prominent Mandible
Retracting the Mandibular Teeth = makes the chin more Prominent
Improving Dental Occlusion while making Jaw Discrepency more Obvious is not successful teatment
Candidate for Class III camouflage :
Reverse Overjet due to Protrussive mandibular incisors & Retrussive Maxillary Incisors
Short Anterior Face Height so that a downward – Backward rotation of Mandible would improve both anterior and posterior Vertical Facial Proportions
VERTICAL PROBLEMS
Skeletal vertical problems do not lend themselves to camouflage by tooth movement
For Short Face Patients = Growth modification involves down and back rotation of mandible without creating anteroposterior mandibular deficiency
Which is why a short face Class III problem is more treatable than a long face one
Long Face pattern of growth is difficult to modify & elongating anterior teeth to close off accompanying open bite is Antithesis of camouflage
Makes Facial appearance worse
Orthognathic Surgery : Vertically Reposition the Maxilla
Bone Anchors = Intrude Posterior Teeth
TREATMENT PLANNING IN SPECIAL CIRCUMSTANCES
DENTAL DISEASE PROBLEMS
Concern that Endodontically treated teeth cannot be moved
As long as PDL is normal Endo treated teeth respond in same manner
Hemisection !!
In General, Prior Endo treatment does not Contraindicate Orthodontic Tooth Movement
Pre Ortho Periodontal Procedures
Free Gingival Grafts
SYSTEMIC DISEASE PROBLEMS
Systemic Diseases = Greater risk for complications
Successful Orthodontic Treatment = Systemic Disease under control
Most common is Diabetes Mellitus (DM)
Diabetes under control = Good Periodontal response to Orthodontic Force
Alveolar Bone Loss !!
Diabetes not controlled = Real risk of Periodontal Breakdown and Bone Loss
Prolonged Orthodontic treatment should be avoided
Juvenile Rheumatoid Arthritis (JRA) = Severe Mandibular Deficiency
Adult onset Rheumatoid Arthritis destroys condylar process
Reduced mandibular growth reported in cases with steroid injections into TM Joint for JRA treatment
Long Term Steroid use = Periodontal Problems during Orthodontics
Children on steroids also take BISPHONATES = Ortho impossible
Prolonged Treatment avoided
Orthodontic Treatment can be carried out in PREGNANCY, but there are risks involved
Gingival Hyperplasia, Hormonal Fluctuations
Bone Turn Over issues = Alveolar bone loss & Root Resorption
Radiographs to check status of bone = not permissible during pregnancy
Treatment should be deferred until completion of pregnancy
If patients becomes Pregnant during Treatment = Place her treatment in a Holding Pattern during Last Trimester
ANOMALIES & JAW INJURIES
MAXILLARY INJURIES
Fortunately, Injuries to maxilla in children are rare
If displaced by Trauma = Immediately repositioned
Protraction force from a face mask before Fractures have completely Healed can Reposition it
ASYMMETRIC MANDIBULAR DEFICIENCY
In planning treatment, its important to evaluate the condyle to see if its translating properly
Functional Appliance should be tried first
Asymmetry with deficient growth on one side and normal on other side = HYBRID FUNCTIONAL APPLIANCE
Requirements will be different for both sides
Restriction of condyle = reduced growth on affected side
Oral & Maxillofacial Surgery = Goal
HEMIMANDIBULAR HYPERTROPHY
Facial asymmetry can also be caused by excessive growth at one condyle
Escape of growing tissues on one side from normal regulatory control
Never Symmetric, Late Teens, Frequently in Girls
Body of mandible affected = Bowing downward
Old name = Condylar Hyperplasia
Treatment = Ramal Osteotomy or Condylectomy