Main Instructor 鄧雅音
Department / Institution Department of Craniofacial Orthodontics, Linkou Chang Gung Memorial Hospital
Classification Case report
To present an atypical extraction strategy in patient with bimaxillary protrusion and asymmetric malocclusion
This case concerned a 21-year-old male whose chief complaint was crooked teeth, lip protrusion and midline discrepancy. An x-ray showed skeletal Class I bimaxillary protrusion and facial asymmetry. Clinical examination showed no functional shift, while the upper dental midline deviated to left side by 2mm and lower deviated to right side by 1mm. There was moderate crowding in both arches, Class II molar relation on the right side and Class I molar relation on the left side. It also showed scissor bite on the upper left second premolar and molar, supraerupted lower left second molar, as well as a subgingivally secondary caries on the upper right second premolar. Extraction of the poor-structured upper right second premolar and three of the first premolars in other quadrants was provided. One miniscrew was placed on the upper right area for anchorage reinforcement and midline correction. The other miniscrew was inserted on the palatal side for scissor bite correction. Despite facial asymmetry and atypical extraction, reduced dental midline discrepancy, solid occlusion and a satisfactory profile were achieved after a two-year treatment.
Discussion and Summary
With the aid of miniscrews, a satisfactory treatment outcome can be attained in case of atypical extraction in Class I bimaxillary protrusion and unilateral scissor bite.
Anchorage Management in Patients with Facial Asymmetry and Midline Discrepancy