Severe mandibular retrognathism: orthodontic versus surgical orthodontic treatment.

1. Treatment of Class II, Division 1 malocclusions should be accomplished by normalization of the abnormal structures that are identified diagnostically. 2. In the presence of mandibular retrognathism and unfavorable growth potential (limited amount, undesirable direction), surgical mandibular lengthening should be incorporated into the treatment plan. 3. Compensation for mandibular retrognathism by conventional orthodontic and facial orthopedic treatment incurs the risk of (a) increase in nasolabial angle, (b) reduction in upper lip support, (c) increase in lower facial concavity, (d) excessive proclination of lower incisors with compromise of labial periodontal support, and (e) protracted duration of appliance therapy and accompanying detrimental periodontal and root resorption effects.