唇弁反転法における移植部の治癒過程に関する実験的研究 : 神経組織学的ならびに Alkaline Phosphatase 活性の変化について

Abstract

Lip switch operation is a grafting method with the full thickness pedicle flap of one lip rotated to repair a defect of the other lip. This pedicle flap contains all tissues of the lip skin, orbicularis oris muscle, and oral mucosa. It is therefore considered that the method would reveal a slightly different healing process from the skin graft performed in the field of Plastic Surgery. Nerve-histological studies reported of the healing process of the flap are few. Consequently, there are unknown facts about the change of the nerve distribution in the grafted flap. Lip switch operations were therefore performed experimentally on the lip of dogs and the healing process was examined nerve-histologically. Furthermore, it was considered that an observation of the changes in alkaline phosphatase activity might clarify a phase of the healing process of the grafted tissue. The changes of enzyme therefore were observed histochemically. The results were as follows. 1. The epithelial layer of the grafted flap began to proliferate by the 3rd day after transplantation, but the mucous epithelial layer of the top of the flaps were degenerating from the 1st day to the 7th day after transplantation. 2. In the subcutaneus and submucous tissue layers of the flap, there were much inflammatory cell infiltration, edema, and vasodilatation at the first stage after transplantation. On the 10th day, they almost disappeared, but the dilated vessels were still seen to the 25th day after transplantation. 3. The muscle fibers in the grafted flap were degenerating to the 10th day after transplantation, but on the 120th day, they came to resemble the normal tissue. 4. Around the 5th day after transplantation, the neoformation of muscle fibers took place by continuous regeneration from muscle fibers of the grafted flap and adjacent tissues at the muscle layer of the junction, and more was seen at the distal (labial angular side) junction. 5. The nerve fibers in the flaps chiefly from the central part to the top degenerated after rotation operation. The nerve fibers in the pedicle part of the flaps degenerated after cutting off the pedicle on the 14th day. 6. By the 5th day after transplantation, the regenerating nerve fibers were seen budding out from the end and the lateral of the nerve fibers at the margin of the muscle layer of the adjacent tissues. On the 15th day, they came to enter the flaps, and on the 20th day, they could be observed in every part of the flaps. 7. Every regenerating nerve fiber in the grafted flap was connected with Schwann cell band. But at the junction, there were also excessive regenerating nerve fibers that had no connection with Schwann cell band, and most of them were degenerating on the 30th day. On the 60th day, the nerve fibers of the junction decreased in number. 8. Around the 45th day after transplantation, the formation of nerve endings was observed in the regenerating fibers. But on the 120th day, the number of endings was less than that of the normal tissue. 9. On the 120th day after transplantation, the condition and maturity of the nerve distribution in the grafted flaps were almost similar to the normal tissue, but in the pedicle part of the flaps, they were still less progressed. 10. In the epidermis of the grafted flap and the adjacent tissues, the basal cell layer showed a slight positive alkaline phosphatase reaction from the 3rd day to the 10th day, while the epithelium was proliferating. 11. In the muscle layer of the flap and the adjacent tissues, the capillaries showing a positive alkaline phosphatase activity increased in number remarkably from the 5th day to the 10th day after transplantation, and from the 6th day to the 11th day after cutting off the pedicle. 12. The changes in alkaline phosphatase activity of the junction were similar to those of the incised wound healing process, that is, the regenerating epithelium showed a positive reaction from the