ABSTRACT

The aim of this study is to determine the soft tissue changes after single and double jaw surgery in skeletal Class 3 malocclusions. The present study was carried on 20 subjects with skeletal Class 3 malocclusions. The subjects divided into two groups equally; 10 of whom had been diagnosed with normal maxilla and mandibular prognatism, formed the first group of study. In this group surgical treatment consisted of only bilateral sagital split osteotomy. The second group had a diagnosis of maxillary retrusion with mandibular prognatism and surgical treatment consisted of simultaneous Le Fort 1 osteotomy to advance the maxilla and bilateral sagital split osteotomy to set back the mandible. From each patient, the preoperative and postoperative (1 year after surgery) radiographs were taken either in centric relation or in centric occlusion with the lips in repose. Ten skeletal and 17 profile measurements were evaluated. Statistical analysis was performed by SPSS programme. In both groups, the skeletal and soft tissue profiles were straightened improving the dentofacial esthetics. Li-B-Pog angle, E-upper lip distance and soft tissue pogonion movement decreased significantly (p < 0.05) and vertical lower lip measurement increased significantly (p < 0.05) in both groups. Vertical and horizontal movement of pronasale showed a significant difference (p < 0.01) between the groups. The profile changes in the double jaw surgery were similiar to those in the mandibular set-back group with the exception of the changes seen in nasal tip projection and elevation.