Class II Div 2 Flashcards
What is the definition of Class II div 2 malocclusion?
- Edge of Lower incisor occludes posterior to the cingulum plateau of the upper inicisor
- Upper incisors are retroclined
- Overjet is reduced and can also be increased
What is the incidence of Class II div2 malocclusion?
- 5-18%
What AP skeletal pattern is Class II div 2 usually associated with?
- Mild or mod sk 2 base
- Can also be sk 1 or sk3
What is the typical vertical skeletal pattern of Class II div 2 malocclusion? What pattern of growth is it associated with?
- Typically reduced (reduced FMPA)
- Often associated with forward rotational pattern of growth of mandible
- Gives prominent chin (Progenia)
What soft tissue associations are there for Class II div 2 malocclusion?
- High resting lower lip line which is secondary to decreased lower face height and gives Retroclination of upper incisors
- Marked labio-mental fold
- High masseteric forces (give orthodontic space closure problems)
- Upper 2’s have shorter clinical crown which escape the effect of the lower lip and trap lower lip
What are the 6 dental features of Class II div 2 malocclusion?
- Retroclined upper and
lower incisors - Deep OB (can be traumatic or non traumatic)
- OJ usually reduced
- Class II buccal segments
- Increased inter-incisal angle
- Upper laterals thin with
poorly developed
cingulum
What is the percentage of Class ii div 2 malocclusion that have a dental anomaly?
- Approx 50% have congenital dental anomaly
- 33% with impacted canine
- 55% >1 developmental dental anomaly with 20% impacted canine and 15% lateral incisor microdontia
Why treat a Class II div 2 malocclusion?
- Aesthetic concerns
- Dental health concerns (Traumatic OB with IOTN DHC 4f)
What 4 factors does txt options depend on?
- Severity of malocclusion
- Age and motivation of pt
- Dental health
- Pts concerns
What are the 4 options of txt for Class II div 2 malocclusion?
- Accept and monitor
- Growth modification
- Camouflage
- Orthognathic txt
When would you chose to Accept the Class II div 2 malocclusion?
- Acceptable aesthetics
- Patient not concerned
/ not suitable - Overbite not a
significant problem
When would you choose the Growth modification txt option for Class II div 2?
- Growing pt during their adolescent growth spurt i.e. Boy 14+-2yrs and Girl 12+-2 years
- Mild to mod Sk 2 pattern
- Convert Class II div 2 into Class II div 1
- Detail occlusion with fixed appliance
What functional appliance can you use for procline the upper incisors?
- Modified Twin block
- Springs or screw
- Upper sectional fixed appliance
What do we mean when attempting to camouflage a Class ii div 2?
- Accept underlying skeletal base relationship
- Aim to treat to class 1 incisor relationship
When can we opt for camouflage for Class II div 2 ?
- Mild to mod Class II skeletal pattern
When choosing to camouflage a Class II div 2 you have to be careful when extracting teeth why?
- Space closure is difficult in low angle cases
- May never close the gap
In order to get a stable correction of Class ii div 2 what do you need to correct ?
- Overbite reduction (will relapse if not corrected)
- Correction of inter-incisal angle (reduction)
How is a inter-incisal angle corrected?
- Palatal root torque upper incisors
- Proclination of lower incisors
What is a risk of Upper incisor torqueing and what do you need to do it correctly?
- Needs adequate cancellous bone palatal to upper incisors
- Risk of root resorption
When would you opt for orthognathic surgery in Class II div 2 maloclussion?
- When AP or Vertical sk pattern is too sever a malocclusion for orthodontics alone
- Non growing pts
- Profile concerns
What two things are the most likely things to relapse after txt?
- Rotated lateral
- Deep overbite
- Long term retention usually required
When is a deep overbite best to correct?
- When pt still growing
- Use growth mod with functional appliance if AP discrepancy
- URA with FABP
