Vitality of intact teeth anterior to the mental foramen after inferior alveolar nerve repositioning: nerve transpositioning versus nerve lateralization

The aim of the present study was to compare two methods used in inferior alveolar nerve (IAN) repositioning to evaluate their effect on the vitality of intact teeth anterior to the mental foramen. Nerve lateralization (NL) is defined as the lateral reflection of the IAN without incisive nerve transection; nerve transposition (NT) involves sacrifice of the incisive nerve. Twenty-one patients were included in this study. Vitality tests for the teeth anterior to the mental foramen, including pulse oximetry and electric pulp testing, were evaluated at 1 week prior to surgery and at 1 week, 1, 3, 6, and 12 months after surgery. Lower lip and chin neurosensory changes were also recorded at the same time intervals by static light touch test with a cotton-tipped applicator and two-point discrimination test with sharp callipers. Vitality tests were negative after the operation in the NT group, while all had normal values at 1 week prior to the operation. In the NL group, only two patients (20%) had negative test results at 1 week after surgery. Lip and chin neurosensory changes in the total transpositions (28 operations) were seen in 7.1% at 1 year after the operation. It appears that NL is a more physiological procedure than NT.