The surgery-first approach in surgical-orthodontic treatment in combination of computer-assisted surgical planning is growing due to the proposed benefits. However, the dental midline deviation to its basal bone might complicate the post-surgical occlusion setup and the surgical planning. The aim of the presentation is to describe the adoption of limited presurgical orthodontic treatment in the surgical-orthodontic treatment for an adult female patient with skeletal class III with the maxillary dental midline deviation.
「Case」 A 21-year-old female Taiwanese presented with a chief complaint of her prognathic mandible, poor facial esthetics, and poor occlusion. The clinical examination revealed a skeletal Class III pattern and dental Class III malocclusion. She had 2 mm of overbite and -3 mm of overjet. She had no remarkable facial asymmetry. However, the upper dental midline was 6 mm to the right due to un-eruption of the upper right canine. The impacted canine was removed. The 6-month limited presurgical orthodontics was proceeded to correct her upper dental midline and coincide her upper dental midline to the maxilla. The transient post-surgical occlusion was established in a Class I relation with coincided dental midlines. After the virtual 3D surgical planning, a two-jaw surgery with counterclockwise rotation of the maxilla-mandibular complex was performed to advance the maxilla and set back the mandible. The post-surgical orthodontics resumed immediately to finish and detail the occlusion. The active treatment was finished in 2 years. The facial attractiveness, well-aligned dentition and solid Class I occlusion were achieved.
「Discussion and summary」
The computer-assisted surgical planning greatly contributes to clinicians to realize the deformities and the surgical changes in three dimensions. In the transient post-surgical model setup, we should coincide the jaw midlines by assessing though the 3D virtual composite model. As the pre-surgical dental midline is off to the facial midline because of the dental malalignment, the limited presurgical orthodontics could be arranged to align the dental midline to the relative jaw bone that could simplify the surgical procedures.