하악전돌증 환자의 하악지 시상분할법에 의한 악교정 수술후 재발에 관한 연구

Skeletal relapse after sagittal split osteotomies for correction of mandibular prognathism

In a study of 20 cases have been investigated clinically and radiologically long term results (6 months and over) of the sagittal split osteotomy technique (Obwegeser - Dal Pont 1961). The overall relapse rate was 30% but reoperation is not required. A statistical analysis of cephalometric radiographs was done and possible causes of relapse was discussed. The results were as following. 1. There are 6 cases of relapse in 20 patients (30%). 2. There are significant correlationship between amount of setback and long term horizontal relapse (p＜0.01). 3. There are significant correlationship between surgical change of mandibular plane angle and long term horizontal relapse(p＜0.01). 4. The direction and amount of vertical changes are irregular and there are no statistical correlationship. 5. The duration of fixation and patients age at operation are not correlated to horizontal relapse. 6. In preoperative cephalometric measurements, mandibular plane angle and gonial angle are not correlated with horizontal relapse. 7. Wire osteosynthesis is inadequate comparing rigid fixation in the aspect of positional stability.