Several types of osteotomy have been performed for correction of mandibular prognathism, retrognathia and assymmetry.The injury of the inferior alvolar nerve as a complication were evaluated in 35 patients after the surgery.
1. Anesthesia, hypesthesia and paresthesia of the lip and mental area were observed in all of the patients (35 cases) in early stage after the operation.
2. 70.8% of the patients who were treated with sagittal splitting osteotomy were recognized as S4 (Highet's standards) within a year.
3. The Average of the sensory nerve conduction velocity (S.C.V.) of normal was approximately 60m/sec.Nerve action potential could not be recorded in early stage and gradually returned to normal S.C.V.from 20 weeks after the surgery.
4. Complete return of the sensation was recognized within 40 weeks after the operation which mandible were moved less than 10mm.
5. There is no difference of return of sensation between circumferencial wiring and bone screw fixation after sagittal splitting osteotomy.
