Document Type : Original Article

Authors

1 Orthodontic Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, IRAN

2 Dept. of Oral and Maxillofacial Surgery, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, IRAN

3 Dept. of Orthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, IRAN

Abstract

Statement of Problem: Adaptation of the soft palate and its morphological alterations do occur to some extent after different surgical strategies of class III patients including mandibular setback, maxillary advancement and bimaxillarysurgery. The precise changes in soft palate morphology are not well understood yet.Purpose: The aim of this study was to conduct a detailed cephalometric evaluation of the alterations taking place in position and morphology of the soft palate after treatment of class III skeletal deformity via different surgical procedures (i.e. mandibular setback, maxillary advancement, bimaxillarysurgery).Materials and Method: 120 consecutive patients who were diagnosed as having skeletal class III deformity were evaluated. All patients included in this study were adults who had completed their growth and had cephalograms within amonth prior to operation (T1) and 1 month to 9 months post-surgery (T2) taken in the natural head position. Patients were divided according to the type of surgery undertaken in three groups: group 1 combination of mandibular andmaxillary (bimaxillary), group 2 (mandibular setback) and group 3 (maxillary advancement) surgery. Soft palate length, depth and thickness were evaluated at both T1 and T2 in each group. The results were compared by paired t and onewayANOVA tests.Results: Soft palate length increased significantly in groups I and III ( p <0.05). Soft palate depth changed significantly in group II ( p <0.05). Soft palate thickness did not changed in any groups ( p >0.05).Conclusion: Soft palate morphology was changed after class III surgeries. Palatal length was increased after maxillary advancement or bimaxillary surgery whereas its depth was increased after mandibular setback or bimaxillary surgery.