골조직과 경조직대치물 인접면의 면역조직화학적 연구

IM M UNO HISTOCHEM ICAL STUDY ON INTERFACE B E T W E E N HOST BONE AND HARD TISSUE REPLACEMENT

Hard Tissue Replacement (HTR) is a synthetic polymer composed of polymethylmethacrylate(PMMA) and polyhydroxyethylmethacrylate(PHEMA). This composite polymer has been used for many clinical conditions such as alveolar ridge augmentation, ridge maintenance and reconstruction of traumatic and neoplastic defects of bone. However, biocompatibility of HTR has not been accetped, and interface reactions between host bone and HTR implant have been reported with variable results. The author has undertaken experimental work on interface tissue reaction between host bone and HTR implant. Twenty-two rabbits were subjected to be implanted with HTR in their parietal ^bones and femurs, and subsequently implanted sites were necropsied for histological and immunohistochemical studies. For immunohistochemical study monoclonal antibodies to fibronectin, vimentin, a-smooth muscle actin and CD 68 were used for identification of primitive cells of mesenchymal origin. At the 4th day of implantation, a thin membranous structure was formed in contact with the polymer. Inflammatory cells and macrophages were intermingled with fibrin in the membrane. This inflammatory capsule became granulation tissue at the 1st week to the second week of implantation. The granulation tissue capsule was characterized by the presence of fibroblasts, osteoblasts and inflammatory cells. At the 4th week to 8th week of implantation, cellularity decreased leaving collagen fibrosis, the fibrous capsule was reminiscent 혔5f scar tissue. The histologic and immunohistochemical study of interface reaction showed that the capsular changes were indentical with those of wound healing. The early inflammatory changes of the capsule around HTR appeared to be resulted from surgical intervention of implantation. Granulation tissue reaction and scar formation in the capusle were thought to be host reaction to the polymer. As the inflammatory reaction through out the experiment was mild in degree, biocompatibility of HTR to the host tissue was apparent.