발치와에 매식한 Hydroxylapatite의 조직반응에 관한 실험적 연구

AN EXPERIMENTAL STUDY OF TISSUE RESPONSES TO HYDROXYLAPATITE IMPLANTED IN EXTRACTION SOCKET

There has long been a search for methods to restore or replace lost, diseased, or congenitally missing bone. Many authorities have favored autogenous bone grafting for this purpose. But, some disadvantages have made it necessary to develop an ideal implant material. Several synthetic materials have been investigated, but recently the calcium phosphate system, in particular hydroxylapatite, has been developed and the subject of intensive investigation. The author performed this study for clarification of the effects of hydroxylapatite to the healing of the extraction wound and surrounding alveolar bone, and its tissue responses. The lower incisors of rabbit were extracted, and the right extraction socket was filled with hydroxylapatite particles for the experimental side. The left extraction socket was treated as usual for the control side. At the postoperative 1,2,3,4,6, and 8 weeks, the radiologic and histologic surveys were done. The results are as follows; 1. At the experimental side, infiltration of inflammatory cells was seen most severely in 1 week group, and became less severe in 2 and 3 weeks group. It was not seen in other groups. 2. At the experimental side, macrophages and multinucleated giant cells were seen in 1 and 2 weeks group, but were not seen in other groups. 3. Resorption of alveolar crest was seen at the experimental sides as well as the control sides. 4. Fatty bone marrow was seen in the control side of 6 and 8 weeks group, but not seen in any experimental sides of 6 groups; The healing process was delayed at the experimental side. 5. After the inflammatory cells, macrophages and multinucleated giant cells were disappeared, the healing process of the experimental side was going on without any other untoward reactions; The hydroxylapatite was compatible to tissue.