Class 2/2 Flashcards
What is the prevalence of class 2/2?
4.5%
What is the definition of class 2/2?
The lower incisor edge lies posterior to the clingulum plateau of the upper incisors and the upper incisors are retroclined
What are the skeletal extra oral features of class2/2?
Sagittal: mild skeletal class 2
Vertical: reduced ALFH and MMA
Transverse: maxillary base broad relative to mandible
Chin: well developed in relation to the slightly retrusive mandible
Profile: pleasing
What are the soft tissue features of class 2/2?
Reduced face height
High Lower lip
Competent lips
What are the dental feature of class 2/2?
Crowded: laterals are mesio labially rotated
Increased overbite
What time of growth oration of people with cl,ass 2/2 have?
Anterior
Why are the upper central retroclined in class 2/2 but not laterals?
The lower lip reclines the upper centrals but because the upper laterals are smaller they often escape the upper lower lip
What is the overjet in class 2/2?
Ave
Increases
Decreased
What is the overbite in class 2/2?
Often deep
Which teeth are commonly in scissor bite?
Upper 4’s
What is the molar relationship often like in class 2/2?
Often class 2
What are the two broad treatment options for class 2/2?
Accept incisor relationship
Or
Correct incisor relationship to class 1 including overbite correction
When would you accept the overbite ?
2/2 not severe
Overbite not traumatic
Pt understands the limit
How do you treat the overbite in class 2/2?
Intrude incisors
Extrude molars
Proclined lower teeth
Surgery
In what type of Patients is it easier to treat the overbite in?
Growing patients because need molars to extrude as this is easier than intruding incisors and by doing so, the patient needs to be able to accommodate this new height
For a more stable overbite reduction what should be done regarding the interim costal angle?
Needs to be changes to 125-135 with 2mm overjet
How do we manage crowding in. Class 2/2?
Extractions are usually avoided but of needs be then take 5 not 4
This is because want to keep incisors labially inclined to
1. Aesthetics
2. Keep lips prominent
3. Low inter incisal reduction and OB reduction
In cases where there is minimal space required?
Distal movement rather than extraction to create space in the upper arch
Use head gear
How would you treat a case where there was more crowding?
Extractions to create space
What other type of appliance may you need to consider with someone of a moderate crowded class 2/2?
An URA to reduce the overbite and to make space for placing a lower FA
When would you use a functional appliance in class 2/2?
In growing patients, may convert them to class 2/1 First URA to procline upper teeth then use Functional appliance to close over jet
When would you use Orthognathic surgery in clas 2/2?
Only those that have stopped growing and the skeletal patten is severe class 2 but mandib advancement may make the chin even more prominent so may also need genioplasty
