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Class II div 1 Malocclusion Class II div 1 Malocclusion

OR

What can we do about Goofy?

Objectives

Objectives

Describe Class II div 1

Objectives

Describe Class II div 1

Describe principles of treatment

Objectives

Describe Class II div 1

Describe principles of treatment Describe treatment options

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Objectives

Describe Class II div 1

Describe principles of treatment

Describe treatment options

Examples of treatment

Aetiology Aetiology

Dento-alveolar

Aetiology

Dento-alveolar

Skeletal

Aetiology Dento-alveolar

Incisor proclination

27

82

79

125

93

Aetiology Dento-alveolar

Incisor proclination

?

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Aetiology Dento-alveolar

Digit sucking?

Aetiology Dento-alveolar

Digit sucking

Aetiology Dento-alveolar

Incisor proclination

Lower incisor

retroclination

27

82

79

125

87

Aetiology Skeletal Aetiology Skeletal

Mild

Aetiology Skeletal

Mild

Moderate

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Aetiology Skeletal

Mild

Moderate

Severe

Aetiology Skeletal

Mild

Moderate

Severe

High FMPA angle

Aetiology Skeletal

Mild

Moderate

Severe

Low FMPA angle

Treatment Principles I Treatment Principles I

Ideal

Treatment Principles I

Ideal correct skeletal discrepancy

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Treatment Principles I

Ideal correct skeletal discrepancy

Camouflage

Treatment Principles I

Ideal correct skeletal discrepancy

Camouflage hide skeletal discrepancy

Treatment Principles I

Ideal correct skeletal discrepancy

Camouflage hide skeletal discrepancy

Depends on patient

Treatment Principles I

Ideal correct skeletal discrepancy

Camouflage hide skeletal discrepancy

Depends on patient

Growing?

Non-growing??

Skeletal discrepancy

Growing patient

Can we make patients

grow?????

Skeletal discrepancy

Growing patient Can we make patients

grow?????

Research studies:

One patient and it works

Series of patients treated and it works

Randomised Clinical Trial

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Skeletal discrepancy Growing patient

Can we make patientsgrow?????

Research studies: Randomised Controlled Trails

North Carolina study

Manchester/UK study

Skeletal discrepancy Growing patient

Functional appliances produce slightly more

mandibular growth

Functional reduce the need for orthognathic surgery

Headgear reduces maxillary growth

Shorter time with fixed, but longer overall

treatment time

North Carolina study shows:Am J Orthod Dentofacial Orthop1998:113:62-72

Skeletal discrepancy Growing patient

Functional appliances produce slightly more

mandibular growth

Early treatment improves self image

Twin blocks as effective as Herbst appliances

UK study shows:OBrien et al 2004

Conclusion

Orthodontic treatment results in

camouflage of skeletal discrepancies

UNLESS patient grows favourably

or surgery is used

Treatment Options

Ideal Correct skeletal discrepancy

Orthognathic Surgery

Functional (if growth occurs)

Camouflage Accept skeletal discrepancy

Reduce overjet within

skeletal limits

Camouflage

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Treatment principles II Treatment principles II

1. Reduce Overbite

Treatment principles II

1. Reduce Overbite

Treatment principles II

1. Reduce Overbite

2. Create space (extraction/non extraction)

..for

Treatment principles II

1. Reduce Overbite

2. Create space (extraction/non extraction)

..for3. Reduction of Overjet +/- relief of Crowding

Treatment options

Non extraction

Extraction

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Non extraction1. Space analysis

2. DMUBS(Distal Movement of Upper

Buccal Segments)

3. Functional

appliances

OR

Space analysis

Assumptions:1. Aims of treatment is Class I occlusion

2. Skeletal I occlusion

3. Premolar extractions

4. Complaint patient

5. Skilled operator using Fixed Appliances

Space analysis

1. Lower labial segment crowding

2. move canines to align lower incisors

3. Add/subtract any lower centre line shift

4. Add lower buccal segment crowding

5. Total = space requirements

Plan lower arch

Space analysis

Plan upper arch

Space analysis

1. Move canines to Class I

2. Add upper buccal segment crowding

3. Total = space requirements

Plan upper arch

Space analysisWhich extractions?

Space less than 2mm non extraction

Space 2-4mm extract 2ndpremolar

Space 4-6mm extract 1stpremolar

Space greater than 6mm anchorage

?

?

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Non extraction

DMUBS

Mild cases needs co-operative patient

Non extraction

Functional

Growing patient

Well aligned arches

Extraction

Most commonly premolars

Space analysis

premolar = 7mm

Extraction

Most commonly premolars

Removable appliance

Extraction

Most commonly

premolars

Removable appliance

Fixed appliance

Suitable for removable

appliances?

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Suitable for removableappliances?

Indications:

1. proclined incisors

2. Mesial angulation of canines

3. Acceptable lower arch

Suitable for removableappliances?

Take Cephalogram and undertake a Prognosis tracing

Suitable for removable appliances?Trace tip upper incisor about a point from apex

Suitable for removable appliances?Extraction

Removable appliance

reduction of overjet.

Indications:

1. proclined incisors

2. Mesial angulation of canines

3. Acceptable lower arch

Usually a compromised result

1. Overbite reduction

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1. Overbite reduction 1. Overbite reductionFlat Anterior Bite Plane

when retracting canines and BEFORE incisor retraction

1. Overbite reductionFlat Anterior Bite Plane - Design

Design must include:

1.Height of bite plane required

2. Length of bite plane

(ie Overjet)

1. Overbite reductionFlat Anterior Bite Plane - Fitting

1. Overbite reductionFlat Anterior Bite Plane - Fitting

Molars

2mm apart

1. Overbite reductionFlat Anterior Bite Plane - USE

FABP may need building up/addition

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2. Overjet reductionDesign:

Flat Anterior Bite Plane maintains OB reduction

Incisor retraction spring e.g. Strap spring e.g.Labial Bow

2. Overjet reductionFlat Anterior Bite Plane maintains OB reduction

2. Overjet reductionFlat Anterior Bite Plane adjustment

Trim behind incisors

to allow retraction

2. Overjet reductionFlat Anterior Bite Plane adjustment

Trim behind incisors

to allow retraction

To be continued