Class II Division 2 Flashcards
What is the BSI definition of Class II Division 2 malocclusion?
The lower incisor occludes posterior to the cingulum plateau of the upper incisor
The upper incisors are retroclined
The overjet is reduced but can also be increased
What is the vertical skeletal pattern for this malocclusion?
Typically reduced
–Reduced FMPA
Often associated with a forward rotational pattern of growth of the mandible
Also a prominent chin (Progenia)
What are the soft tissues like associated with this malocclusion?
A high resting lower lip line
Marked labio-mental fold
High masseteric forces- ortho space closure problems
Upper 2’s show clinical crown
–escape the effect of the lower lip
–trap lower lip
What are the dental features of this malocclusion?
Retroclined upper and lower incisors
Deep OB
OJ usually reduced
Class II buccal segments
Increased inter-incisal angle
Upper laterals thin with poorly developed cingulum
What do treatment options depend on?
Severity of malocclusion
Age and motivation of patient
Dental Health
Patients concerns
Why treat this malocclusion?
Aesthetic concerns
Dental health concerns
–Traumatic overbite
–IOTN 4f
What are the treatment options for this malocclusion?
Accept
Growth modification
Camouflage
Orthognathic treatment
Why would a patient chose to accept this malocclusion?
Acceptable aesthetics
Patient not concerned/not suitable
Overbite not a significant problem
When would you use growth modification for this malocclusion?
Growing patient
–Adolescent growth spurt
–Boys 14 +/- 2 years
–Girls 12 +/- 2 years
Mild to moderate skeletal 2 pattern
Convert Class II div 2 into Class II div 1
Detail occlusion with fixed appliances
What kind of twin blocks would you use and for how long?
Modified twin block
6-9 months
When would you use camouflage treatment for this malocclusion?
Accepting the underlying skeletal base relationship and aiming to treat class I incisor relationship
Mild to moderate Class II skeletal pattern
Careful extraction decision
–Space closure difficult in low angle cases
What would fixed appliances do to this malocclusion?
Stable correction of Class II div 2 needs
–Overbite reduction
–Correction of inter-incisal angle (reduction)
Overbite will relapse if not corrected
Inter-incisal angle corrected by a combination of
–Palatal root torque upper incisors
–Proclination of lower incisors
Upper incisor torqueing
–Needs adequate cancellous bone palatal to upper incisors
–Risk of root resorption
What does orthognathic surgery involve for this malocclusion?
Too severe a malocclusion for orthodontics alone
Non growing patients
Profile concerns
When should a GDP refer?
Deep overbites are best corrected when the patient is growing
–Growth modification with functional appliance if AP discrepancy
–URA with FABP
Orthognathic/orthodontics if significant skeletal component (after growth completed)
What is a modified twin block?
Upper bite block is trimmed to allow lower molars to erupt which reduces the deep overbite and increases the lower facial height
