Treatment of crowding in permanent dentition Copyright (c) Department of Orthodontics University of Dental Medicine, Yangon

1. TreaTmenTTreaTmenT
ofof
CrowdingCrowding
in PermanenT denTiTionin PermanenT denTiTion
Dr.Hla Hla Yee

2. CausesCauses

Generalized crowdingGeneralized crowding
(Jaw size tooth size discrepancy )(Jaw size tooth size discrepancy )

Localized crowdingLocalized crowding
• Supernumerary teethSupernumerary teeth
• Retained deciduousRetained deciduous
• Early loss of primary teethEarly loss of primary teeth
• MacrodontiaMacrodontia
• Tooth size discrepancyTooth size discrepancy

3. DiagonsisDiagonsis
 Space analysisSpace analysis
 Tooth size analysisTooth size analysis
 Radiographic examinationRadiographic examination

4. TreatmentTreatment
depend on severity of crowdingdepend on severity of crowding
SpaceSpace
discrepanciesdiscrepancies
 Up to 4mmUp to 4mm
 5mm to 9mm5mm to 9mm
Treatment ProtocolTreatment Protocol
 Non-extractionNon-extraction

DiskingDisking

ExpansionExpansion
(except for third molar)(except for third molar)
 Non-extractionNon-extraction

ExpansionExpansion
oror
 Extractionof some teethExtractionof some teeth
other than third molarother than third molar

5.  10mm or more10mm or more  Extraction regardlessExtraction regardless
of what happen toof what happen to
third molar at laterthird molar at later
statestate

6. Treatment PlanningTreatment Planning
for Crowdingfor Crowding
 Based on lower archBased on lower arch
 If crowding in lower arch is minimal andIf crowding in lower arch is minimal and
incisors are in correct position, acceptincisors are in correct position, accept
lower incisor crowding.lower incisor crowding.
 If crowding in lower arch is moderate orIf crowding in lower arch is moderate or
severe , correct lower incisor crowding.severe , correct lower incisor crowding.

7. Treatment Planning Cont’dTreatment Planning Cont’d
 Correction of crowding in permanentCorrection of crowding in permanent
dentition requires extraction or expansiondentition requires extraction or expansion
 Diagnosis set upDiagnosis set up
 Type of tooth movement requiredType of tooth movement required
 Choice of appliance and mechanotherapyChoice of appliance and mechanotherapy

8. Treatment ofTreatment of
Orthodontic problems associatedOrthodontic problems associated
with Supernumerary teethwith Supernumerary teeth
Extra teeth in addition to the normal number of teeth in a given
dentition.
It is rare to see extra teeth in the deciduous dentition.
Types
-Supplementary teeth
-Conical supernumerary teeth
-Tuberculate supernumerary teeth

14. Orthodontic problems associatedOrthodontic problems associated
with supernumerary teethwith supernumerary teeth
 Deviation of the eruption path of permanentDeviation of the eruption path of permanent
succedaneous teeth .succedaneous teeth .
eg. Proclination, rotation, displacementeg. Proclination, rotation, displacement
 Median diastemaMedian diastema
 Delayed eruption of permanent succedaneous teethDelayed eruption of permanent succedaneous teeth
 Dilaceration or abnormal root development ofDilaceration or abnormal root development of
permanent teeth.permanent teeth.

15. DiagnosisDiagnosis
 Clinical examinationClinical examination

Count the teethCount the teeth

Palpation should be carried out up into thePalpation should be carried out up into the
labial sulcus and in some cases the outline oflabial sulcus and in some cases the outline of
the tooth may be felt in this situation.the tooth may be felt in this situation.

16.  Radiographic examinationRadiographic examination

Standard occlusal viewStandard occlusal view

PA viewPA view

Parallax view ( to determine the bucco-palatalParallax view ( to determine the bucco-palatal
relation )relation )

18. Treatment OptionsTreatment Options
 ( 1 ) No treatment( 1 ) No treatment
 ( 2 ) Extraction of the erupted supernumerary( 2 ) Extraction of the erupted supernumerary
 ( 3 ) Surgical removal of unerupted( 3 ) Surgical removal of unerupted
supernumerarysupernumerary

to permit the proper eruption of normalto permit the proper eruption of normal
dentitiondentition

to prevent malposition of teethto prevent malposition of teeth

19.  Early surgical removal of supernumerary teethEarly surgical removal of supernumerary teeth
 AdvantagesAdvantages

Spontaneous eruptive potential of permanentSpontaneous eruptive potential of permanent
incisors.incisors.

To prevent anterior space closure and midlineTo prevent anterior space closure and midline
shiftshift
- Therefore,- Therefore, Early detection and removal ofEarly detection and removal of
supernumerary teeth are important for interception orsupernumerary teeth are important for interception or
prevention of malocclusionprevention of malocclusion

Supernumerary teeth should be removedSupernumerary teeth should be removed
immediately before complicated orthodonticimmediately before complicated orthodontic
problem occur.problem occur.

20.  DisadvantagesDisadvantages

Potential damage to adjacent teeth resulting inPotential damage to adjacent teeth resulting in
deviatalization and/or root malformation.deviatalization and/or root malformation.

Inability of a young child to psychologicallyInability of a young child to psychologically
tolerate the surgical procedure.tolerate the surgical procedure.

21.  Delayed intervention denotes observationDelayed intervention denotes observation
until adjacent root formation is completeuntil adjacent root formation is complete
which is generally between 8 and 10 yearswhich is generally between 8 and 10 years
of age.of age.
 AdvantageAdvantage

Less danger of damaging the growingLess danger of damaging the growing
mesenchymal portion of the permanent teeth.mesenchymal portion of the permanent teeth.

22.  DisadvantagesDisadvantages

1 )Less of eruptive potential of the central1 )Less of eruptive potential of the central
incisorsincisors

2 )Loss of anterior arch space or midline shift2 )Loss of anterior arch space or midline shift

3 )More extensive surgical and orthodontic3 )More extensive surgical and orthodontic
treatment for correctiontreatment for correction

4 )Increased in vertical height of the premaxilla4 )Increased in vertical height of the premaxilla
will accentuate the difficulty of surgical accesswill accentuate the difficulty of surgical access
to unerupted supernumeraryto unerupted supernumerary

23.  Treat the orthodontic problemsTreat the orthodontic problems
 Space analysisSpace analysis

If adequate space exist - treat the conditionIf adequate space exist - treat the condition
• ( 1 )Realignment of adjacent permanent teeth( 1 )Realignment of adjacent permanent teeth
• Correction of proclinationCorrection of proclination
• Correction of rotationCorrection of rotation
• Correction of displacementCorrection of displacement
• ( 3 ) orthodontic extrusion of permanent teeth( 3 ) orthodontic extrusion of permanent teeth
• ( 2 ) Approximation of adjacent teeth( 2 ) Approximation of adjacent teeth

24. 
If space deficiency is presentIf space deficiency is present
• Create the space for correction of orthodonticCreate the space for correction of orthodontic
problems depend on severity of crowdingproblems depend on severity of crowding

( disking, expansion or extraction of permanent teeth )( disking, expansion or extraction of permanent teeth )

Type of tooth movementType of tooth movement

Choice of applianceChoice of appliance

MechanotherapyMechanotherapy

25. Rotation of IncisorsRotation of Incisors

26. CausesCauses
 Retained primary teethRetained primary teeth
 Supernumerary teethSupernumerary teeth
 CrowdingCrowding
 Habits – nail bitingHabits – nail biting

27. ManagementManagement
 Investigate, identify and remove the causeInvestigate, identify and remove the cause
 Correct rotation earlyCorrect rotation early

28. ApplianceAppliance
 Use a removable appliance to apply forceUse a removable appliance to apply force
couplecouple
 Fixed – removable applianceFixed – removable appliance
( Whip spring )( Whip spring )
 Fixed applianceFixed appliance