Aim: The BSSO is an excellent operation for a mandibular setback. Beyond 7-8 mm of posterior repositioning of the mandible with a BSSO is difficult, and consideration should be given to an inverted L osteotomy or intraoral vertical ramus osteotomy. (IVRO) Currently the period of immobilization ranges between 7-21 days following the release of IMF, guiding elastics should be used to direct the mandible to maximal intercuspation.
Materials and Methods: This study implied a 1 year follow- up on a group of 40 patients, who had undergone modified subcondylar osteotomy for mandibular setback. Relapse is measured as the distance from Sn perpendicular to Pog at the lateral cephalogram preoperative, one week, and one year postoperatively.
Conclusion: Modified intra-oral subcondylar osteotomy with short term immobilization appeared to be a relatively safeeand reliable procedure.
The mean skeletal horizontal relapse at Pog of the whole group, after one year was 0.6mm and neuro-senory disturbance (NSD) incidence alter 6 months was 2.5%.