early treatment in ortho

1

Early Treatment in Orthodontics

Dr. Suzan [email protected]

Division of OrthodonticsUniversity of Minnesota

2007

OutlineI. Definitions and Terms:

Early TreatmentPreventive, Interceptive, CorrectivePhase I, Phase II

II. Specific goals of early treatment

III. Non skeletal orthodontic issues:CrowdingEruption DisturbancesAnterior Crossbites

IV. Skeletal orthodontic issues:Transverse problemsVertical problemsGrowth Modification

V. Summary and Cases

I. Definitions and Terms

Early Treatment: Treatment initiated during the primary or mixed dentition with the purpose to prevent, intercept or correct a specific orthodontic problem or problems, also known as, Phase I treatment.

I. Definitions and TermsPreventive early treatment:Patient education and maintenance of a favorable orthodontic condition.

e.g. patient education of stopping digit sucking habits, space maintenance appliances.

Interceptive early treatment:Improvement of an orthodontic problem.

e.g. Primary tooth guidance extractions, reduction of excessive overjet, growth modification appliances, space redistribution, space creation, deep bite reduction, habit appliances.

Corrective:Complete or nearly complete correction of an orthodontic problem.

e.g. Expansion appliances, growth modification appliances, alignment of anterior teeth.

I. Definitions and TermsPhase I

Treatment initiated during the primary or mixed dentition with the purpose to prevent, intercept or correct an orthodontic problem, also known as, early treatment.

Phase IITreatment initiated during the permanent dentition with a comprehensive approach to correcting the orthodontic problems, also known as, comprehensive treatment.

II. Specific Goals of Early Treatment

Overall goal of early treatment:To improve or correct orthodontic problems that would result in:

Irreversible damage to the dentition and supporting structuresProgression into a more severe orthodontic problem that would be more difficult to treatment in Phase II.

2

II. Specific Goals of Early Treatment

Specific goals of early treatmentClearly defined endpoints of phase I orthodontic treatment.

Why is this important?To prevent extended Phase I treatment times

Patient cooperation anticipatedDamage to unerupted teeth

Phase II is still likely for most cases

II. Specific Goals of Early Treatment1. Improved Psychosocial Development

Self-Esteem, esthetics2. Improved Occlusal Function

Symmetry, shifts/slides, attrition

3. Manage potential for damage to dentitionTrauma, attrition, recession, injury, primary tooth extractions.

4. Phase II simplificationGrowth modification, space management, primary tooth extractions

5. Improved or corrected skeletal discrepanciesSymmetry, reduce skeletal discrepancies, transverse problems.

II. Specific Goals of Early TreatmentConsider the 4 factors in the development ofthe dentition:1. Eruption Guidance2. Growth Orthopedics3. Drift Space Control4. Equilibrium Habit Control

BenefitsImproved patient socializationBetter patient cooperationEarlier correctionSometimes fewer extractions requiredSometimes less orthognathicsurgery required

RisksMisdiagnosisExtended treatment timeGreater cost (time and money)Patient burnoutIncreased caries risk

I. Definitions and Terms:Early TreatmentPreventive, Interceptive, CorrectivePhase I, Phase II


III. Non skeletal orthodontic issues:CrowdingAnterior CrossbitesEruption Disturbances



III. NON SKELETAL ORTHODONTIC ISSUES

CrowdingAnterior CrossbitesEruption Disturbances

3

Classification of Mixed Dentition Crowding

Incisor Liability – mild amount of transitional crowding of the permanent incisors in a mixed dentition (~2-3mm).

Permanent Mn incisor widths = interdental spaces of primary teeth + primate

spaces + permanent incisor inclination

Classification of Mixed Dentition Crowding

Moderate Transitional Crowding

~ 4mm of anterior crowding

Severe Transitional Crowding

~ >4mm of anterior crowding

Crowding Management

Treatment options for moderate and severe crowding in a mixed dentition depends on:

Preventing irreversible damagePromoting eruption of teeth into attached gingivaClass I, II or III dental and skeletal growth patternIncisor proclinationMidline shifted or centeredEstheticsLeeway space available for crowding or molar correction.

Leeway Space

Moyers –2.5mm per side in Mn2.0mm per side in Mx

Proffit –1.7mm per side in Mn0.9mm per side in Mx

Used for:CrowdingMolar drift

Crowding Management

Options:No treatment and monitorSpace Maintainers Extract primary canines ±LLHA

Arch width expansion Incisor proclinationDistalizers – lip bumpers, headgear etc.

Maintains current arch perimeter

Increases arch perimeter

Lower Lingual Holding Arch

LLHA

Holds arch perimeter as the permanent teeth erupt.

4

Severe Transitional CrowdingSigns:

Lack of interdental spaces in primary dentition.>4mm of crowding of permanent incisors.Early loss of primary canine by ectopic eruption of lateral incisor.Ectopic eruption of upper first permanent molars.

Serial ExtractionDefinition:

A planned sequence of tooth removal during the transition from primary to permanent dentition to promote eruption of teeth through attached gingiva (keratinized tissue) and reduce the severity of crowding.

Eruption sequence of the permanent dentition:Maxilla: 6 1 2 4 5 3 7 8Mandible: 6 1 2 (3 4) 5 7 8

Serial Extraction

Ideal Case Selection Requirements:

1. No skeletal disproportions; balanced AP, V, T dimensions

2. Class I molar 3. Non-retrusive lip profile4. Normal overbite5. Coincident midlines6. Severe crowding warranting

extractions.

Serial Extraction

Timing of extraction: ½ to ¾ root development of 1st PMs to accelerate eruption.Phase II full braces for alignment, bite and root parallelism.



Ectopic eruption of maxillary first permanent molarsMesiodensAnkylosed primary molars

Anterior Crossbites

Lingual eruption of a maxillary incisor relative to the mandibular incisor.With or without a shiftTraumatic occlusion possibleLower anterior recession possible

5




Ectopic Eruption of Maxillary First Molar

Ectopic eruption is a developmental disturbance in the eruption of the permanent dentition where the first permanent molar erupts with a mesialangulation and resorbs the distal root aspect of the primary second molar.

Ectopic Eruption of Maxillary First Molar

ReversibleSpontaneous correction

IrreversibleWithout treatment will continue to resorb the primary molar towards early exfoliation and compete for arch space with the second premolar.

Prevalence of 4%

Ectopic Molar Appliance

Usually in young childrenTreatment sometimes not possible due to cooperation or compliance.Effective if molar is accessible

Mesiodens

Presentation:Delayed eruption of incisorsDiastemaSeverely displaced incisorEctopic or asymmetric eruption of central incisorsErupted supernumerary tooth in midline

What is happening here?

6

Ankylosed Primary MolarsPrevalence of 9-13%

Presentation:Submerging primary molarPrimary molar below occlusal plane

Issues:Missing successorDelayed eruption of successorProgressive infraocclusionLoss of arch lengthDifficult extraction with potential bony defect if no successor.Posterior lateral open bite









III. SKELETAL ORTHODONTIC ISSUES

Transverse problemsVertical ProblemsGrowth Modification

Transverse Problems in the Mixed Dentition

Definition: Posterior CrossbiteWhen the upper teeth bite on the inside of the lower teeth.

Classification:Unilateral or BilateralWith or without a shiftDental or Skeletal

Expander AppliancesHow do they work?

Rapid or slow expansion Turning frequency

Skeletal expansion: Separates the:midpalatal suturecircumzygomatic and circummaxillary sutures.Creates a diastema

Dental expansion:Tipping, therefore overcorrection.

Cannot accomplish skeletal expansion once suture is fused.

7

Expander Appliances

Hyrax Appliance Bonded Expander

Vertical Problems in the Mixed Dentition

• Open Bites

• Deep Bites

Open BitesDental open bite

Related to a digit habit Reversibility related to the age the habit is stopped.

80% spontaneously correct if stopped before 9yo.Otherwise, may consider a habit reminder appliance.

Skeletal open biteIncreased dentoalveolar heightSupereruption of maxillary teethPhenotype: short posterior face height, long anterior face height, high MPA, retruded mandible, maxillary constriction.

Habit Reminder Appliances

Anterior Crib Appliance Blue Grass Appliance

Skeletal Open Bite early treatment?

Partial braces (2x4 appliances)High Pull HeadgearChin CupTranspalatal arch (TPA)Lower lingual arch (LLA)Tonsillectomy/adenoidnectomy

Variable results with skeletal early treatmentsMany are case reportsLong term stability is questionable

May need to monitor growth and consider orthognathic surgery in the future.

Lower Lingual Arch Transpalatal Arch

8

Vertical Problems in the Mixed Dentition

• Open Bites

• Deep Bites

Deep Bites

Dental deep biteExtrusion of anterior teeth

Skeletal deep biteLack of alveolar developmentOverclosure

Deep bites range from:Slightly excessive (50%)Palatally impinging (100%)

Deep bite early treatment

Anterior bite platePartial braces

2x4 appliances

The Bite Plate Effect

III. SKELETAL ORTHODONTIC ISSUES

Transverse problemsVertical ProblemsGrowth Modification

Growth Modification

Class IIClass III

Class II Growth Modification

Class IIMandibular deficiency, maxillary excess or combinationProfile: retrognathic, convexMolar classification: Class IISkeletal discrepancy of jaw growthCommonly measured using the ANB angle

9


Indications for Phase I treatment:For psychosocial benefit (evidence to support)Decreased risk of tooth fracture if accident occurs. (evidence to support)

For better cooperation (some evidence to support)To take advantage of an earlier growth spurt (some evidence to support, but growth is so variable that it is difficult to select cases)


Skeletal/Orthopedic appliances:HeadgearsFunctional appliances

Dental appliances:PendulumPartial braces

Orthopedic Appliances: HG Orthopedic Appliances: FA

Bionator (Removable) Herbst - Fixed

Dental Distalizers

Pendulum Appliance Pendex Appliance

Growth Modification

Class IIClass III

10

Class III Growth Modification

Findings:Negative ANB angleMandibular prognathismMaxillary deficientCombinationNegative overjet

Class III Growth Modification

Indications for Phase I treatment:For psychosocial benefit Removal of shift Pseudo class IIIIncisal wear risk

For better cooperation To avoid future need for surgery?

Treatment Appliances

Skeletal/Orthopedic Options:Protraction Facemask ± RMEChin cup

Dental options:Expansion2x4 appliances

“Early Class III treatment is one of the most difficult undertakings mainly due to the uncertainty of the outcome’s stability after active growth.” Westwood et al.

Protraction facemask ± RME






Summary:Anterior CrossbitesPrimary molar ankylosisImpinging deep OBEctopic eruptionSevere crowding Loss of arch space or symmetry Excessive overjetsHabitsOpen bitesPosterior CrossbitesGrowth discrepancies

11

Milestone appointments:7yo – first orthodontic evaluation

Supernumerary or missing teethGrowth pattern, eruption schedule

8yo –Degree of crowdingPosterior or Anterior CrossbitesClass I, II or IIIDeep bite, open bite, habits

10yo – Look for permanent canine position

11yo – late mixed dentition

Possible need for Phase I treatment

Possible need for Phase II or

comprehensive treatment

CASES

Open Bites: What are some differences?

Anterior Crossbites:What are some differences?

Deep Bites: What would you check next?

What early treatment issues do you see?

12

What early treatment issues do you see?



III. Non skeletal orthodontic issues:CrowdingEruption DisturbancesAnterior Crossbites



Early Treatment in Orthodontics

Dr. Suzan [email protected]

Division of OrthodonticsUniversity of Minnesota

2007

early treatment in ortho

Documents