The Efficacy Of Computer Guided Surgery In Preserving Ramal Height And Skull Base During Gap-Arthroplasty In Patients With TMJ Bony Ankylosis

Abstract

Purpose:The aim of the study was to compare between computer guided surgery and the traditional method in preserving vertical ramus height (VRH) and the skull base thickness during gap arthroplasty in patients with the TMJ bony ankylosis. Material and methods: Twelve patients with 15 joints suffering from true bony TMJ ankylosis were included in this study. The patients were divided into 2 groups: Group A (8 joints); The ankylosis was released by computer-assisted 1cm gap arthroplasty. Group B (7 joints); The ankylosis was released by traditional 1cm gap arthroplasty. Pre and postoperative clinical examinations included: measurements of maximum interincisal opening, midline deviations or deflections during mouth opening or closing, presence of open bite, recording any sign/symptoms of infection, facial nerve function evaluation. Preoperative radiograph were measure the preoperative VRH, and aid in construction of the surgical guide for group A, while, postoperative radiograph performed for measure the VRH and skull base thickness. Result: Clinically improvement in the midline shift and occlusion during physiotherapy period postoperatively for all cases in group A except in one patient. While, clinical result in group B revealed increase in the midline shift, and change in occlusion postoperatively. Radiographically: there was no statistical significant difference between the 2 groups in postoperative VRH loss measurements. There was statistical significant difference between the 2 groups in postoperative skull base thickness. Conclusion: Computer assisted surgical simulation could help the surgeon to preserve the VRH and the skull base that reflects positively on the postoperative clinical outcomes.