Clinical Assessment & Presentations
Extra-oral Features
Start your assessment by looking at the patient’s extra-oral features.
Protrusive facial and lip patterns
Bimaxillary dentoalveolar protrusion can often be noted facially and on lateral cephalograms.
3/4 profile depicting incompetent and everted lips
Profile depicting protrusive lips relative to the nose and chin
Lateral cephalogram with proclined incisors and narrow alveolar ridge width
Adapted from Chung et al. 2009
Intra-oral Features
Proclined incisors
A bimaxillary dentoalveolar protrusion incisor relationship is usually one which has more proclined upper and lower incisors. There may be a decreased overbite or an anterior open bite. An increased incisor overjet may be present due to an overall Class II malocclusion but a Class III incisor relationship may exist as well.
Flat smile arc
Bimaxillary dentoalveolar protrusion cases will often have a flat smile arc because the upper incisors are overly proclined. The proclination reduces the relative incisal edge steps between the central incisors to lateral incisors and canines, typically seen in an ideal (curved) smile arc.
A flat smile arc has resulted as the incisors are too proclined
An ideal smile arc with incisors at the correct angulation
Alveolar ridge width
The alveolar width at the anterior jaws are a significant factor in bimaxillary dentoaveolar protrusive cases. The size of the alveolar width will determine if proclined incisors can be treated orthodontically only. Proclined incisors housed in a thin alveolar ridge cannot be retracted or uprighted within their alveolar ridge without compromising gingival attachment, root exposure, or root resorption.
Posterior occlusion
The posterior occlusion can be variable in bimaxillary dentoalveolar protrusion cases. It may present as Class I, II or III sagittal relationships, with normal or abnormal transverse relationships and with crowding or spacing.
