Parallel osteotome technique: new approach to reduce neurosensory disturbances following bilateral sagittal split osteotomy.

Abstract

To determine clinically if parallel osteotome technique (POST) reduces incidence of neurosensory disturbances (NSD) following bilateral sagittal split osteotomy (BSSO), and to corroborate the findings with finite element analysis (FEA). The investigation was a quasi-experimental study involving 30 patients requiring BSSO. The sample was divided into two groups: control undergoing conventional osteotomy technique and experimental using POST. An FEA simulation of the two advocated techniques were also generated for computational analysis. Primary outcome was clinical comparison of subjective and objective measures for NSD, while secondary outcome was comparison of stress, strain and deformation. Osteotomy technique was the exposure studied. Data was analyzed for differences in proportions and means. Thirty patients (12 females and 18 males) with an age range of 18 to 28 (mean 21.6) years were recruited for the study. This provided 60 sides as sample for the study. The experimental group demonstrated significantly lower subjective scores for NSD for the 3 rd (p=0.03) and 6 th month reviews (p=0.025). Objective testing revealed lower incidence of NSD for the experimental group during the 3 rd (p=0.07), 6 th (p=0.007) and 12 th post-operative months (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 method. Incidence of NSD following BSSO is lower with POST. The technique also induces significantly lower deformational forces on the IAN when compared with the conventional osteotomy method.