The L-shaped Zygomatic Reduction with Oblique or Vertical Resection: Which One is the Optimal Choice?

This study aims to investigate the optimal surgical techniques in reduction malarplasty by comparing the difference between the L-shaped osteotomy with vertical and oblique bone resection.One hundred and twenty patients who visited our department for L-shaped osteotomy with either vertical (Group Ⅰ) or oblique bone resection (Group Ⅱ) from 2015 to 2021 were retrospectively reviewed. The preoperative and postoperative spiral computed tomography (CT) data were analyzed. The preoperative CT data was also used to simulate the virtual and model surgery.The results showed that a broken-bridge-like structure with a bony gap of 2.86±1.03 mm at the zygomatic arch root was observed in Group Ⅰ, and a mortice and tenon joint structure with a bone overlap of 2.28±0.58 mm was formed in Group Ⅱ. The zygoma in Group Ⅰ displaced significantly in the vertical direction and horizontal direction during the follow-up. Simultaneously, the incidence of complications was higher in Group Ⅰ. In the mechanism analysis through virtual and model surgery, the zygomatic segment was shifted anteriorly and inferiorly in Group Ⅰ, and a bony gap was detected at the zygomatic arch root. Conversely, a superior and posterior movement was performed in Group Ⅱ and it maintained the zygomatic complex integral with bone overlap at the zygomatic arch root upon repositioning.This study suggested that L-shaped osteotomy with oblique bone resection could be the optimal choice for reducing zygomatic prominence.