Histologic Study Of Different Bioceramic Implants In Intrabony Defects

골내낭에 매식된 수종의 생체요법재료에 대한 조직학적 연구

The purpose of this study was designed to compare with the effects of 4 different surface active bioceramics on the healing process of alveolar bone defects in dogs. Artificial alveolar bone defects depth 4-6mm, width 3-4mm) were created with # 6 round bur at interproximal areas of maxillary canine, maxillary 2nd premolar, mandibular canine, and mandibular 3rd premolar. porous hydroxyapatite(Interpore $200^R$) , 45S5 bioglass, CJ4/lOC crystalline glass, and JJ crystalline glass were implanted in intrabony defects randomly. Experimental groups were divided into 4 categories according to its implant material. After implantation, all groups were examined postoperatively 4 weeks to 12 weeks. 3 dogs was selected randomly and sacrificed after vascular perfusion with 2.5% glutaraldehyde at every 4 weeks. Tissue blocks with surroundig alveolar bone and soft tissues were removed and immersed in formaldehyde/glutaraldehyde fixative. After 20 weeks decalcification with EDTA and formic acid, sections were made and observed under light microscope and transmission electron microscope. In all experimental groups, the encapsulation of inactive connective tissue was observed around graft particles in 4 weeks. As time elapsed, the thickness of surrounding connective tissue was decreased. Osteoconductive bone growth pattern was seen apparently in all groups. CJ4/lOC crystalline glass showed the most active bone formation until 8 weeks. 45S5 bioglass was, however, the most active in new bone formation at 12 weeks. Though there was difference in resorption rate among grafting materials, the size of graft particles was decreased gradually. 45S5 bioglass was resorbed faster than the others. On the other hand, porous hydroxyapatite was degraded most slowly. Phagocytosed particulate matters was observed in the cytoplasm of multinuclear multinuclear giant cell and macrophage under transmission electron microscope. The results suggested suggested that 45S5 bioglass and CJ4/lOC crystalline glass may have some enhanced reparative potential when compared to porous hydroxapatite in the treatment of periodontal defeds. JJ crystalline glass reguires a further investigation of the safety of its use.