Development and Evaluation of Synthetic Bone Graft Materials for Periodontal Tissue Regeneration and Carriers

Purpose: The aim of this study was to evaluate the enhanced biocompatibility and mechanical properties of various newly developed carriers and osteoconductivity of bone graft materials in several studies conducted at Department of Periodontology, Yonsei University College of Dentistry, Seoul, Korea. Materials and Methods: Studies were performed divided into the following two different subjects. 1) Development and evaluation of mechanical strength, biocompatibility and drug release capacity of new carriers: gelatin-layered and multi-sized porous β-tricalcium phosphate (β-TCP), hollow hydroxyapatite spherical granules and porous calcium polyphosphate granules. 2) Evaluation of bone regeneration of various particlulated bone graft materials: alloplast (demineralized bone matrix [DBM] gel), xenoplast (bovine bone), synthetic bone (hydroxyapatite, β-TCP, biphasic calcium phosphate [BCP]) and block bone graft materials: nano-hydroxyapatite block bone and bovine hydroxyapatite/collagen block. Results: Gelatin-coated multi-sized porous β-TCP showed enhanced compressive strength and affected cell viability and differentiation. Penetrability of drugs can be controlled by change of structure and pore properties of hollow hydroxyapatite spherical granules. Pore size and porosity of porous calcium phosphate influenced the osteogenic differentiation and cell differentiation. Even though limited volume stability of DBM gel was observed, bone regeneration of various graft materials was not significantly different. In particular, superior new bone formation in BCP and large resorption of β-TCP was observed among various calcium phosphate materials (hydroxyapatite, β-TCP and BCP). Block bone graft materials had better stability and space-maintaining capacity in one wall intrabony defects. Conclusion: With the potentials and limitations of the suggested list of studies, effective carriers and various bone graft materials can be used for better periodontal regeneration in aspect of enhanced osteogenic properties and further studies are required for proper selection and application of materials in various intrabony defects.