Bone Morfojenetik Protein-6 Ve Insülin Benzeri Büyüme Faktörü-I'in Kontrollü Ardışık Salımının Sementoblast Hücreleri Üzerine Etkileri

Abstract

Periodontitis is an infectious disease which causes loss of tooth supporting structures. The goal of periodontal therapy is to improve periodontal health by means of removal of local factors which initiate and progress periodontal infection. Conventional periodontal therapies can stop disease progression but often result in “repair” or scar formation, not reproducing the structures lost in the disease process. Periodontal regeneration is histologically defined as regeneration of tooth supporting structures including alveolar bone, periodontal ligament and cementum and it is a complicated process. Growth and differentiation factors (GDF) are polypeptites which regulate cell functions. These factors are known as competence or progression factors and they provide continuity of cell cycle. Therefore for continuity of cell growth process, these two group of factors are needed to act together. However, clinical use of growth factors have two shortcomes: cost and short biological half-life which limit their effects on cells regenerating the periodontium. Therefore by using scaffold systems, it is needed to provide their controlled release. Chitosan is a biocompatible natural polymer which has positive effects on wound healing. The goals of this study are to develop micro and nanoparticles loaded chitosan carriers for controlled and sequential delivery, to observe protein release kinetics of IGF-I (competence factor) and BMP-6 (progression factor) which are loaded into micro and nanoparticles and to test the effects of released factors on various cell functions and protein expression of cementoblasts. For sequential and controlled release of growth factors, composite structure was fabricated from being encapsulated IGF-I loaded microparticles and BMP-6 loaded nanoparticles in chitosan scaffold. After the characterisation of in vitro release kinetics, the effects of scaffolds on cementoblasts were determined. Cementoblast cell proliferation was measured with MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-Diphenyltetrazolium Bromide) assay. Depending on the results, both IGF-I and BMP-6 containing composite structures showed greater effects of MTT assay at 2, 4, 8, 12th days compared with control groups. In addition, cementoblasts differentiation and mineralized tissue formation potentials were also increased in composite structure, compared with control groups. As a conclusion, composite structure, composed of micro and nanoparticles and chitosan, is an appropriate scaffolds for periodontal regeneration applications via providing sequential and controlled release and have a promising future for tissue engineering approaches.