Histomorphometric observations of surgical methods for partial amputation injury of the inferior alveolar nerve using polyglycolic acid

Abstract

ObjectiveThis study aimed to establish the best materials to use for the surgical repair of partial nerve amputation injuries. MethodsWe induced partial nerve amputation injuries to the inferior alveolar nerves of rabbits that were divided into the non-wrapping, polyglycolic acid (PGA) wrapping, vein wrapping, and atelocollagen wrapping groups. The inferior alveolar nerve of each rabbit was resected at half of the nerve fascicle diameter (5mm wide), and the injured portion was promptly wrapped and surgically repaired. Sensory nerve action potential (SNAP) and histomorphometric observations were recorded at 4, 8, and 12 weeks postoperatively. ResultsThe fibrous connective tissue and nerve fiber that were regenerated were complicated; in the histomorphometric observations, samples in the non-wrapping and atelocollagen wrapping groups were mixed and showed neural scarring. In the PGA and vein wrapping groups, the nerve fibers regenerated without invading the fibrous connective tissue. The regenerated fibers looked good, particularly in the PGA group, and showed continued epineurium during nervous regeneration. The SNAP of the regenerated fibers had delayed maximal conduction velocity and amplitude regeneration compared with the normal inferior alveolar nerves in all groups. All groups had maximal conduction velocity and amplitude improvement week by week. The PGA wrapping group had the most favorable regeneration. ConclusionOur study demonstrated that PGA was the most useful wrapping material.