[The experimental study on inside-out vein graft for repairing inferior alveolar nerve defect in the rabbit]

This study describes a modification of the vein graft technique inside-out vein graft, creates an autogenous vein conduct with the collagen-rich and Schwann cells exposed to regenerating axons. To compare regeneration of inferior alveolar nerves through two conduits: inside-out vein graft and the standard vein graft.

18 adult white rabbits were selected and vena facialises of both sides were harvested. Turned the right vena facialis into inside-out vein and used to bridge an 8 mm defect created in the right inferior alveolar nerve. An 8 mm defect of the left inferior alveolar nerve was bridged by the standard vein graft. After rabbits sacrificed at 8, 14 and 20 weeks, the regenerating nerve cables were harvested from the conduits and performed histologic study. At 20 weeks, performed also electrophysiologic studies and statistical analysis of conductive velocities and histological results.

Regenerating nerves connected with proximal and distal nerve stumps on both sides postoperation 8 weeks, a number of regenerating nerve fibers and thickness of axon were gradually increasing. At 20 weeks regenerating nerve on the inside-out vein graft side showed superior function results--faster conduction velocities (P < 0.05) and distinct histological results--much more axon counts (P < 0.05) and thicker mylin sheaths (P < 0.05) compared with contralateral standard vein graft.

The adventitial surface of vein promotes nerve regeneration by an environment with collagen-rich and Schwann cells. The inside-out vein graft is an original way to repair inferior alveolar nerve.