Assessment of mandibular bony healing, mandibular condyle and angulus after orthognathic surgery using fractal dimension method.

BACKGROUND This study aims to compare the trabeculation changes in the bone structure observed at the mandibular osteotomy line and the mandibular condyle in patients after single and double-jaw orthognathic surgery. MATERIAL AND METHODS The study included 38 patients (23 female, 15 male) who underwent mandibular surgery with bilateral sagittal split ramus osteotomy technique. The patients were divided into two groups according to their surgical operation: single-jaw (bilateral sagittal split ramus osteotomy) or double-jaw (Le Fort I osteotomy and bilateral sagittal split ramus osteotomy) surgery. Trabecular changes seen in mandibular osteotomy lines, mandibular condyle and mandibular angulus were evaluated on panoramic radiographs of patients (preoperative, postoperative 2nd day, postoperative 3rd month and 12th month) using fractal analysis method. Fractal dimension analysis was calculated by box counting method. RESULTS No statistically significant difference was found between the fractal analysis values in the mandibular condyle and angulus region preoperatively, postoperative 2nd day, postoperative 3rd month and postoperative 12th month in the single jaw group. There was no statistically significant difference between the fractal analysis values in the mandibular condyle and angulus region preoperatively, postoperative 2nd day, postoperative 3rd month and postoperative 12th month in the double jaw group. A significant difference was found in fractal analysis values in osteotomy lines in both groups. The lowest value was found on the 2nd postoperative day and reached the preoperative values in the 3rd and 12th months postoperatively. Fractal analysis values didn't show significant difference between the single, double-jaw groups in all periods. CONCLUSIONS This result suggests that the fractal analysis method can be used to evaluate trabeculation in the bone healing process of the osteotomy lines and indirectly affected areas in the postoperative period after orthognathic surgery.