COMBINED ORTHODONTIC - SURGICAL TREATMENT OF SEVERE SKELETAL CLASS III MALOCLUSSION

Abstract

Severe skeletal Class III caused by mandibular prognathism often requires a combined orthodontic and surgical treatment to ensure a stable therapeutic outcome. This case presents the therapeutic approach for a male patient who had a 1/2 / Class III malocclusion, an anterior open bite of 3 mm, anterior crossbite and a concave profile before initiating orthodontic treatment. The initial lateral cephalogram indicated mandibular prognathism (SNB 83°), a skeletal Class III (ANB -1°) with a tendency towards an open bite (B 31°), proclination of the upper incisors (I/SpP 59°), and retroclination of the lower incisors (i/ MP 92°). Additionally, an increased mandibular corpus length of 4 mm was observed. The second lateral cephalogram, taken immediately before surgical intervention indicated a skeletal Class III (ANB -3°), an increased mandibular corpus by 5.85 mm, and corrected inclinations of the upper and lower incisors. Presurgical treatment with fixed appliances lasted 36 months, followed by bimaxillary surgery. Postsurgical orthodontic treatment lasted 8 months, during which the patient wore vertical intermaxillary elastics to establish a stable occlusion. At the end of the treatment, Class I occlusion was achieved with proper overbite and overjet, and a harmonious facial profile. The post-surgical lateral cephalogram showed correction from Class III to Class I skeletal relationship, proper inclination of the upper and lower incisors, and corrected mandibular corpus length. Combined orthodontic - surgical treatment can effectively correct severe skeletal discrepancies caused by mandibular overdevelopment.