Evaluation the effect of sagital split osteotomy on mandibular range of motion dut to mandibular setback

Document Type : original article

Authors

1 Assistant Professor, Dept.of Oral & Maxillofacial Surgery, Dental school, Mashhad university of Medical Sciences.Mashhad, Iran

2 Assistant Professor, Dept.of Oral & Maxillofacial Surgery, Dental school, Esfahan university of Medical Sciences.Esfahan , Iran

Abstract

Introduction:
In the orthognatic surgery of the mandible and specially bilateral sagital spilt osteotomy (B.S.S.O), the most complication is some change in mandibular border movement, and as a result limitation of mandibular movement. The aim of this study was to evaluate the changes in maximum interincisal opening, left and right lateral excursion, and protrusive movements in all patients before and after operation in the period of three to six months and the effects of modern physiotherapical plans (CPM) on increasing these movements after surgery.
Materials and Methods:
This is a prospective clinical trial study. In this study 30 patient,s (18 females & 12 males) who were 13-30 years old (average age 20.5), BSSO surgery was performed according to Epker procedure with surgical handpice and bur, rigid fixation were performed with 3 postional screw of 2mm diameter for all patients. MIO, LLE, RLE, PM were measured before and after operation in the period of three to six months. At the end the patients who still had mandibular movement limitations were divided into two groups of experiment and sample, then the effects of 20 physiotherapical sessions were studied after the 9th month.
Results:
After 3 months post-op, considerable reduction in all mandibular movements has occured, but after 6 months post-op, 12 patients (40%) had significant limitation of mandibular movements, specially in MIO & PM. At the end of nine months post-op all patients in sample group, had limitation in mandibular mobility but in the experiment group all patients had normal mandibular border movement.
Discussion:
There are different reports about the effect of orthognatic surgery on mandibular border movements. In this study BSSO for mandibular setback has led to considerable reduction in mandibular movement sepecially maximum interincisal opening & protrusive movements and the physiotherapical treatment have been considered as the solution of the mentioned problems but the major difference between our study and others are, using of Rigid fixation, not using MMF and two week usage of elastic Traning. 

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