Evaluation of Three- Dimensional Rhombic Plate in Open Reduction and Internal Fixation of Subcondylar Fractures of Mandible: A Pilot Study

Abstract Background: Fractures of condyle of mandible are quite common and it constitutes about 25% to 50% of mandibular fractures. Open reduction and internal fixation (ORIF) of these fractures may range from use of 1 or 2 miniplates to the use of 3- dimensional (3-D) titanium plates. In recent times 3-D plates of different geometrical configurations are being used. These geometrical configurations are delta, trifix, rhombic and trapezoidal. This study was done to explore the efficacy of 3-D rhombic plate for ORIF of subcondylar fractures of the mandible.     Aim & Objectives: The aim of the study was to evaluate the efficacy of 3-D rhombic plate for ORIF of subcondylar fractures of mandible in terms of stability of fixation and to document the associated postoperative complications.   Material & Methods: This non-randomized clinical trial was conducted in 10 patients having isolated mandibular subcondylar fracture with disturbed occlusion. The ORIF of subcondylar fracture was done by using transparotid approach followed by fixation with 3-D titanium rhombic plate & 6 mm titanium screws. The primary outcome variables assessed were stability of fixation (as indicated by stable occlusion), restoration of jaw function in terms of mandibular movement (as assessed by maximum mouth opening) and bite force registration. The secondary outcome variables were postoperative complications such as infection, wound dehiscence, parotid fistula, facial nerve injury and hardware failure. Additionally, these complications were categorized according to degree of severity and recovery pattern with or without management. The parameters under evaluation were assessed at different time intervals at 1st, 7th, 15th day, 1 month and 3 months postoperatively. The data obtained was statistically analysed by Statistical Package for Social Sciences (SPSS) software package (SPSS 16 Inc, Chicago IL, USA).   Results & Observations: The age of the patients involved in the study ranges from 19 to 50 years with the mean age of 28.4±8.9 years. Out of 10 patients, 8 were males (80%) and 2 were females (20%). The occlusion was disturbed pre-operatively in all the patients enrolled in the study which was an essential inclusion criterion of the study. At 1st and 7 postoperative day the occlusion was stable in 7 patients (70%) and was deranged in 3 patients (30%). After elastic traction the occlusion was achieved and maxilla-mandibular fixation (MMF) was applied for 1 week. The occlusion remains stable in all the patients at 1st and 3rd months postoperatively. When maximum mouth opening was assessed, it was restricted at 1st postoperative day. There was statistically significant improvement in mouth opening at each time interval postoperatively. When bite force was evaluated post-operatively, there was statistically significant improvement at each time interval. When postoperative complications were considered, there was only 1 case of wound dehiscence and 1 case of facial paralysis. We have not encountered any case of postoperative infection, parotid fistula and hardware failure postoperatively.      Conclusion: The use of rhombic plate for ORIF of subcondylar fractures is quite promising and is associated with fewer complications. However, long term studies with larger sample size are necessary to make some definite recommendations.