Asymmetric mandibular arch distalization with third-molar extractions for nonsurgical correction of skeletal Class III open bite and mandibular deviation: A case report

Rationale: This case report aimed to describe a premolar preservation, nonsurgical approach for adult skeletal Class III open bite using third-molar extraction and buccal-shelf miniscrew-anchored mandibular arch distalization. Patient concerns: A 27-year-old female presenting with a 2 mm anterior open bite, bilateral Class III molar and canine relationships, mild bimaxillary crowding, and midline deviations underwent extraction of all third molars. Diagnoses: Skeletal Class III malocclusion secondary to excessive mandibular growth in a horizontal growth pattern, Class III dental relationships with marked proclination of the maxillary and mandibular incisors, anterior crossbite and open bite, and leftward mandibular deviation. Interventions: Fixed appliances were bonded to initiate leveling and alignment. Two buccal-shelf miniscrews provided anchorage for en-masse mandibular distalization with power chains and Class III elastics. Interproximal enamel reduction refined the incisal morphology of both the maxillary and mandibular incisors. Outcomes: After 19 months of active treatment, all objectives were achieved. Bilateral Class I canine and molar relationships were established, overjet normalized from –1.4 mm to +2.8 mm, and overbite from –1.8 mm to +0.9 mm. The upper lip remained essentially stable, whereas roughly 2 mm of lower-lip retrusion permitted the upper lip to overlap the lower. Both arches were well leveled and aligned, with coincident dental and facial midlines. Lessons: Selective third-molar extraction combined with buccal-shelf miniscrew-anchored mandibular distalization is an effective nonsurgical alternative for adult skeletal Class III open-bite cases, preserving healthy premolars and delivering stable occlusal and esthetic outcomes.