The design of osteotomy plane in ortl10gnathic surgery has been developed to diminish tl1e nerve injury. Lntraoral Vertico-Sagittal Ramus Osteotomy (NSRO) is the one of the best way to minimize untoward results, which is designed not to expose the lin...
The design of osteotomy plane in ortl10gnathic surgery has been developed to diminish tl1e nerve injury. Lntraoral Vertico-Sagittal Ramus Osteotomy (NSRO) is the one of the best way to minimize untoward results, which is designed not to expose the lingula.
We evaluated tl1e nerve damage before and after with current perception threshold (CPT) test which is modem and numerically expressible way of nerve damages. Sixty patients underwent NSRO since 1998 were evaluated. They were divided into 2 groups; one group underwent NSRO only, and tl1e other underwent NSRO plus genioplasty. The both groups were evaluated with CPT test 1 week before surgery, and 1, 3 and 6 months after surgery. The CPT test was performed on A-beta, A-delta and C fiber respectively.
The result showed that the recovery of sensory function of damaged nerve fibers was observed at the period of three to six months after surgery.
There was no impairment of nerve function after only the NSRO. But there were sensory disturbances in cases of additional genioplasty group.
We thought that one of major factors on nerve damages were exposure of nerve and traction injury during genioplasty.