Reduced somatosensory impairment by piezosurgery during orthognathic surgery of the mandible.

PURPOSE: This clinical trial aimed to test the hypothesis that piezosurgery causes reduced nerval irritations and, thus, reduced somatosensory impairment when used in orthognathic surgery of the mandible. METHODS: To this end, 37 consecutive patients with Angle Class II and III malocclusion were treated using bilateral sagittal split osteotomies (BSSO) of the mandible. In a split mouth design, randomized one side of the mandible was operated using a conventional saw, while a piezosurgery device was used on the contralateral side. In order to test the individual qualities of somatosensory function, quantitative sensory testings (QSTs) were performed 1 month, 6 months and 1 year after surgery. RESULTS: A comparison of the data using a two-way analysis of variance (ANOVA) revealed a significant reduction in postoperative impairment in warm detection threshold (WDT) (P = 0.046), a decreased dynamic mechanical allodynia (ALL) (P = 0.002) and a decreased vibration detection threshold (VDT) (P = 0.030) on the piezosurgery side of the mandible as opposed to the conventionally operated control side. In the remaining QSTs, minor deviations from the preoperative baseline conditions and a more rapid regression could be observed. CONCLUSIONS: Piezosurgery caused reduced somatosensory impairment and a faster recovery of somatosensory functions in the present investigation.