Z-shaped Miniplates vs Conventional Miniplates for Fixation of Mandibular Parasymphyseal Fractures.

Aim: The aim of this study was to evaluate a clinically and radiographically Z-shaped miniplate for the fixation of the parasymphyseal fractures.

Patients And Methods: Twenty patients (10 patients in each group) who had parasymphseal mandibular fractures were randomly selected for this study. In this study, open reduction and internal fixation were performed for mandibular parasymphyseal region fractures using two miniplates as group I, and open reduction and internal fixation were performed for mandibular parasymphyseal region fractures using a newly designed Z-shaped miniplate as group II. Clinical and radiographic evaluations were made. Each patient was evaluated: (1) clinically evaluated preoperatively and postoperatively for operating time, ease of placement of the miniplate, and occlusion and (2) radiological: postoperative reduction of fracture was evaluated radiologically at 5-day, 1-month, 2-month, and 3-month intervals with orthopantomogram, and lingual splaying was evaluated by cone-beam computed tomography (CBCT) immediately postoperatively and at an interval of 3 months. The collected data were subjected to statistical analysis. Data analysis was performed by SPSS software, version 25 (SPSS Inc., PASW statistics for Windows version 25). Chicago: SPSS Inc.

Results: There was a statistically significant difference ( < 0.001) between the mean intraoperative time. This indicates that group I had a longer time for fracture fixation than group II. Group I had a longer time elapsed for plate adaptation and definitive fixation than group II. Occlusion and reduction stability in both groups were similar. There was a statistically significant difference in postoperative lingual display control after 5 days and 3 months between the studied groups. This indicates that lingual display control in group II is better than in group I.

Conclusion: The Z-shaped miniplate is effective and provides three-dimensional stability for the fixation of parasymphyseal fractures, ease of use, easily adapted in cases of fractures near the mental nerve reduced operative time, and better control of lingual splaying than conventional miniplates.

Clinical Significance: The newly designed Z-shaped miniplate is a valuable option for fixation parasymphysis fractures that need open reduction and internal fixation instead of using conventional miniplates, which are less successful in controlling lingual splaying.