Parallel Osteotome Technique: New Approach to Reduce Neurosensory Disturbances following Bilateral Sagittal Split Osteotomy.

Background: The purpose of this study was to determine clinically whether the parallel osteotome technique (POST) reduces the incidence of neurosensory disturbances (NSDs) following bilateral sagittal split osteotomy (BSSO), and to corroborate the findings with finite element analysis.

Methods: The authors conducted a quasiexperimental study of 30 patients requiring BSSO. The sample was divided into two groups: a control group who underwent the conventional osteotomy technique and an experimental group who underwent POST osteotomy. A finite element analysis simulation of the two techniques was also generated for computational analysis. The primary outcome was clinical comparison of subjective and objective measures for NSDs; the secondary outcome was a comparison of stress, strain, and deformation. The osteotomy technique was the exposure studied. Data were analyzed for differences in proportions and means.

Results: Thirty patients (12 female and 18 male patients; age range, 18 to 28 years; mean age, 21.6 years) were recruited for the study, providing 60 sides as a sample. The experimental group had significantly lower subjective scores for NSD at the 3-month ( P = 0.03) and 6-month follow-ups ( P = 0.025). Objective testing revealed a lower incidence of NSDs for the experimental group during postoperative months 3 ( P = 0.07), 6 ( P = 0.007), and 12 ( P = 0.17). The computational analysis also revealed significantly lower stress ( P = 0.007), strain ( P = 0.009), and deformation ( P = 0.04) on the inferior alveolar nerve with the POST osteotomy.

Conclusions: The incidence of NSDs following BSSO is lower with the POST osteotomy. This technique also induced significantly lower deformational forces on the inferior alveolar nerve when compared with the conventional osteotomy.