Class II Div 1 Malocclusion Flashcards
what is the BSI classification for a class II division 1 malocclusion
lower incisor edges lie posterior to cingulum plateau of upper incisors
increased overjet
upper central incisors are proclined
what are the two main reasons its important to treat CLass II division 1 malocclusions
aesthetic concerns
dental health - trauma
what are the four overall aetiological factors of a class II div 1 malocclusion
skeletal pattern
soft tissues
dental factors
habits
what can an overjet be due to
skeletal pattern
tooth inclination
what is the normal values for SNA on a lateral ceph
81 degrees (plus and minus 3)
what is the normal values for SNB angle on a lateral ceph
78 (plus or minus 3)
what is the normal ANB angle for a lateral ceph
3 (plus or minus 2)
what soft tissue feature can be an aetiological factor in class II division 1 malocclusions
lower lip trap
what habits can cause a class II division 1 malocclusion
sucking habits
what are five occlusal features of a sucking habit
proclination of upper incisors
retroclination of lower incisors
localised AOB
narrow upper arch
possible unilateral posterior crossbite
what are five management options for treatment of class II division 1 malocclusions
accept
attempt growth modification
simple tipping of teeth
camouflage
orthognathic surgery
what features would make you more inclined to accept a class II div 1 malocclusion
overjet is mildly increased
significant overjet but pt is not unhappy
what appliances can be used to attempt growth modification
headgear - tries to restrain growth of maxilla horizontally or vertically
functional appliance
what are the two broad types of functional appliances
removable or fixed
what are examples of removable functional appliances
toothborne - twinblock
what is an example of a fixed functional appliance
herbst
what is the aim of a functional appliance in class II div 1 malocclusions
restraint of maxillary growth and encourage mandibular growth
when should a functional appliance be used
during growth - if possible coincide with pubertal growth spurt
what are four dento-alveolar changes caused by functional appliance use
distal movement of upper teeth
mesial movement of lower teeth
retroclination of upper incisors
proclination of lower incisors
what are two disadvantages of functional appliances
skeletal effects not maintained long term
treatment time increased due to two phase treatment
what are three benefits of functional appliance use
improves appearance earlier
reduce risk of trauma
better compliance with appliance wear
what is the active component when trying to retrocline anterior teeth
robert’s retractor with 0.5mm ID tubing - include mesial stops
when might orthognathic surgery be indicated for class II div 1 malocclusions
skeletal discrepancy is severe in AP or vertical plane
