Class II div 2 Flashcards
What is the BSI definition of class 2 div 2 ?
- The lower incisors occlude posterior to the cingulum plateau of the upper incisors , the upper incisors are retroclined with reduced or increased overjet
With which skeletal class is class 2 div 2 associated?
Usually with class 2 (mild or moderate)
Can also be Sk1 or Sk3
Describe the vertical skeletal pattern associated with class 2 div 2?
- Reduced FMPA
- prominent chin
- forward rotational pattern of growth of the mandible
3 soft tissue features associated with class 2 div 2?
- High resting lower lip
- Marked labio-mental fold
- High masseteric forces
The high resting lower lip line is secondary to________?
Reduced lower face height
High resting lower lip line in class 2 div 2 leads to ____?
Retroclination of upper incisors, but sometimes upper 2s escape this effect leading to a lower lip trap of the 2s
What problems might be associated with increased masseteric forces in class 2 div 2?
Orthodontic space closure problems
5 dental features of class 2 div 2?
- Retroclination of upper central incisors and lower incisors
- Deep overbite
- Usually reduced OJ
- Class II buccal segments
- Increased interincisal angle
- Thin upper laterals with poorly developed cingulum
Describe how would the upper lateral incisors appear in class 2 div 2?
- Often crowded as mesio-labially rotated
- Poor cingulum and thin
- may be normal or proclined depending on their position relative to the lower lip
2 developmental dental anomalies associated with class 2 div 2?
- Impacted canines
- Lateral incisor microdontia
2 ways the lower incisors can occlude in class 2 div 2?
- with upper incisors or palatal mucosa
IOTN of class 2 div 2 with a traumatic overbite?
4f
Why would you treat class 2 div 2?
- Aesthetics
- Dental health - traumatic overbite
What do ortho treatment options depend on ?
- Severity of malocclusion
- Age and motivation of patient
- Dental health
- Patient concerns
4 treatment options for class 2 div 2?
- Accept
- Growth modification
- Camouflage
- Orthognathic surgery
3 reasons why you would accept a class 2 div 2 malocclusion?
- Acceptable aesthetics
- Patient not concerned
- Overbite is not a significant problem
In boys when is it suitable to attempt growth modification?
Age of 14 ±2
In girl when is it suitable to attempt growth modification?
Age of 12±2
2 indications of growth modification in Class II div 2 malocclusion?
- Growing patient
- Mild to moderate skeletal 2 pattern
What would growth modification achieve in class 2 div 2 ?
- Convert class 2 div 2 into class 2 div 1 by proclination of upper incisors
3 functional appliances that can be used for growth modification of class 2 div 2?
- Modified Twin block
- Springs or screws
- Upper sectional appliances
Indications for camouflaging class 2 div 2
- Mild to moderate class 2 skeletal pattern
- Needs extractions
- Accepting the underlying skeletal base and aiming for class 1 incisor relationship
To correct class 2 div 2 using functional appliances , What do you need to achieve?
- Reduction of overbite
- Reduction of inter-incisal angle
What movements of functional appliance would correct the inter-incisal angle in class 2 div 2?
- Palatal root torque of upper incisors
- Proclination of lower incisors
What would be the main risk in torquing upper incisors?
- Risk of root resorption , that is why you need adequate cancellous bone palatal to the upper incisors
When would render to orthognathic surgery to correct class 2 div 2?
- Severe skeletal relationship in vertical or AP direction
- Non growing patients
- Profile concerns
Which two features are more likely to relapse?
- rotated laterals
- Deep overbite
2 ways to correct an overbite?
- Growth modification with functional appliance ( if AP descrepency)
- URA with FABP
