顎骨欠損に対する自家肋骨移植創の神経線維の消長について

Abstract

Partial bone defect of the mandible was made in adult dogs and a fresh autogenous rib-bone was grafted in each. A neuropathohistological study was made of the nerve distribution in the healing process of fresh autogenous rib-bone graft wounds. Results are summarized as follows : 1. General healing process as studied in the present fresh autogenous rib-bone grafted wounds seemed to follow the usual pattern of wound healing. 2. From 3rd day after grafting, the nerve fibers in the grafted rib-bone began to degenerate and completely disappeared on 7th day. 3. From 3rd day to 5th day, the central inferior alveoral nerve suffered a slight degeneration, or so-called primary degeneration. 4. On 3rd day at the peripheral side, the inferior alveolar nerve and the nerve fibers of the bone marrow reached the height of degeneration. On 7th day, the nerve fibers of the bone marrow disappeared and the inferior alveolar nerve on 15th day. 5. Regeneration of the nerve fibers at the grafted site started on 5th day in the central bone marrow, and on 7th day in the central inferior alveolar nerve. The regenerated nerve fibers reached the part of the peripheral conjunction on 45th day after grafting. 6. On 70th day after grafting, infiltration and proliferation of the Schwann cells from the central and peripheral inferior canals were found at the trabecula in the grafted bone. On 30th day, the regenerated nerve fibers penetrated into these arears. These regenerated nerve fibers extended mainly from the central inferior alveolar nerve but there were some penetrating from the wall of the wound and the periosteum. 7. On 180th day after grafting, the distribution of the nerve fibers in the grafted bone was normal. 8. Formation of the bony space appearing to be the inferior canal occured in the grafted bone on 120th day. The usual large nerve bundle was not observed in the bony space even on 180th day after grafting. 9. In the peripheral inferior canal, regenerated nerve fibers were found penetrating from the central side through the grafted bone and the graft-wounds. 10. On 180th day, the distribution of the nerve fibers in the peripheral bone marrow and the periodontium was nearly the same as that of the normal ones. As is stated above, it is clear that autogenous rib-bone graft for bone defect greatly affects nerve distribution, especially regeneration of the inferior alveolar nerve in the healing process of the graft wound.