Periodontal Tissue Regeneration In Basic And Applied Research Of Composite Materials

The potential to regenerate lost periodontal tissues has been an area of considerable interest and also a formidable challenge to peridontists for many years. Several studies have shown that the periodontal ligament contains undifferentiated mesenchymal cells with the potential to form new cementum, bone and periodontal ligament. It has also been shown that, greater and more predictable regeneration will occur if the epithelial cells and connective tissue cells are blocked from entering the healing surgical wound and if periodontal ligament cells (PDL cells) are guided into the defect. The term guided tissue regeneration (GTR) was coined to describe the technique and biologic principle of selective cell repopulation of the periodontal wound area. GTR is a process that creates an environment which. following a periodontal flap procedure and placement of a biocompatible barrier, only allows cells from the periodontal ligament to selectively repopulate a debrided root surface and form a new periodontal attachment. The initiation and promotion of osteogenesis is the central problem of periodontal regeneration. Research into the molecular initiators of bone differentiation has culminated , in the identification of an entirely new family of proteins, the bone morphogenetic proteins (BMPs), which regulate cartilage and bone differentiation in vivo.The aim of this study was to further understand the relationship of BMP and PDL cells using cell culture, flow cytometry, immunocytochemistry, in situ hybridization techniques. We also reformed the GTR membrane by adding BMP in it, and with the histopathological and animal experimental methods, observed the potential role and application for regeneration procedures in periodontal therapy.A cell line was established from human PDL tissues and was characterized according to morphology, growth pattern, cytoskeletal proteins, and growth kinetics. BMPs were prepared by extracting bovine demineralized bone matrix with 4M Gu-HCL, and with osteogenic activity in the muscle space of the rat. The effects of BMP on alkaline phosphatase (ALPase) activity and proliferation of PDL cells were significantly increased by using MTT and enzyme kinetics methods. Immunohistochemical study using flow cytometer (FCM) showed that PDL cells were positive to monoclonal antibody against BMP. The expression of BMP7 gene was observed using in situ hybridization and showed positive reaction. These may indicate that human PDL cellshave the phenotype of osteoblast-like cells and can secrete BMPs. We also observed...