Lag screw versus wire osteosynthesis in mandibular advancement.

The records of two homogeneous groups of mandibular advancement patients were selected from the 1961 to 1985 files of the Department of Maxillofacial Surgery, University of Zurich. The groups were differentiated by the osteosynthesis technique: lag screw or wire. The preoperative, short-term postoperative, and 1-year postoperative lateral cephalograms of both groups were subjected to the same digitizing procedure and statistical analysis. The mean sagittal relapse of 11% in the rigid osteosynthesis group was not statistically significant, whereas the wire fixation group experienced mean regression of 45% at pogonion after 1 year.