Stability after surgical correction of mandibular prognathism using the sagittal split ramus osteotomy and fixation with poly-L-lactic acid (PLLA) screws.

PURPOSE: This study was designed to examine skeletal stability after surgical correction of mandibular prognathism using a sagittal split ramus osteotomy (SSRO) and fixation with poly-L-lactic acid (PLLA) screws.

PATIENTS AND

METHODS

Twenty patients with Class III malocclusion were treated with bilateral SSRO and mandibular setback. Ten underwent fixation with titanium screws (group I) and the other 10 with PLLA screws (group II). Cephalograms were obtained 2 or 3 days postoperatively, and at 3, 6, and 12 months after the operation. Changes in the position of upper incisors (U-1), lower incisors (L-1), B-point, and pogonion were examined on lateral cephalograms.

RESULTS

Certain tendencies for overjet and overbite were noted to have decreased more markedly, and changes in the position of the skeletal points were greater in group II than in group I. However, statistical analysis showed no significant differences between the two groups.

CONCLUSION

Our results suggest that fixation of the bony segments with PLLA screws after SSRO may be used effectively in properly selected cases.