13 - Class 2 Division 2 Malocclusion Flashcards
Identify the Class II div II malocclusion
Class 2 division 2 incisor relationship
Definition
Class 2 division 2 malocclusion
Incidence
Main aetiology:
Examination
Profile assessment -
In class II patients there is an instep in the profile
Can be due to the maxilla or mandible:
- Maxilla could be further forward
- Mandible could be further back
Normally in Class II div II, it’s the mandible that is positioned further back
Mild skeletal II
Examination class 2 div 2 - Anterior Posterior
Anterior Posterior:
- Usually a mild skeletal II
- Convex facial profile
- Prominent chin
- Competent lips – Sometimes the lips mask the malocclusion
Mild mandibular retrusion on right clinical photograph, competent lips
But sometimes cannot tell if pt is class 2 div 2 frmo profile - such as left clinical photo - as lips are masking the malocclusion
Skeletal vertical assessment In class 2 div 2
Decreased vertical dimension -> deep over bite
Examination - vertical:
Lower face height + Frankfort mandibular plane angle reduced (FMPA) -> Deep bite
Reduced lower face height + FMPA (line between lower border of orbit and tragus, and see where intersection is- usu behind occiput)
Skeletal factors - Transverse
- Posterior Crossbites
- Transverse square faces.
- Well developed gonial angle (as tend to have well developed masseter muscles, square appearance )
Examination - Soft Tissue class 2 div 2
Left image - normal lip line 5-6mm of upper incisor shows at rest
Middle image - high lip line
Google labiomental fold - helps understanding
Examination Dental
Extra - Incisors erupt normally but as high lip line, pressure exerted up upper incisors leading them to retrocline and then lower incisors retrocline
Increased curve of Spee - caused by overeruption of the lower incisors
Interincisal angle - angle between u and l incisors should be approx 135 degrees , in class 2 div 2 - angle increases
Examination dental cont
Examination
Mandibular position
Swelling pattern
Growth
Radiographs - Cephalometric values
ANB - usu mild
Typically mandible is retronathic
Upper incisors typically retroclined
Lower incisors to mandibular plane also retroclined
Interincisal angle is larger
Vertical dimension - mmpa is smaller
Face height ratio is reduced
Treatment planning - 3 things required prior :
Why do we treat class 2 Div 2?
Class 2 div 2 Findings
Treatment depends on
3 categories of treatment options for skeletal problem
Most pt are mild - so orthodontic camouflage would be most common
Treatment options: Orthodontic Camouflage
Aims of treatment
MAIN TREATMENT FOR CLASS 2 DIV 2 - used for mild skeletal 2 and reduced vertical skeletal
Crowding correction
Mild crowding:
Moderate - Severe Crowding:
If patient didn’t have mild skeletal problem can either do which 2 treatments
- Growth modification -> correct skeletal problem - if children and had growth potential
- orthognathic surgery -> Correct skeletal problem - if adult
Moderate - severe skeletal 2
Commonly find which 3 things?
Aims of treatment
What 2 things must we do to correct dental problems?
Growth modification
How are skeletal problems corrected?
How are dental problems corrected?
Stages:
Treatment timing:
Which severity of skeletal issue?
