Biomaterials used as bone graft substitutes

Abstract

Introduction: In daily practice doctors encounter clinical situations in which pacients suffer from insufficient hard and soft tissue volume and quality, caused either by edentation or by different postraumatic, postoperative defects, congenital malformations, etc. In order to satisfy the ideal goals of dentistry, especially of the implant-prosthetic rehabilitation,bone regeneration procedures are performed. Any implanted material that alone or in combination with other materials promotes a bone healing response by providing oteogenic, osteoinductive or osteoconductive properties is called a bone graft. Purpose and objectives: Enhancing the efficiency of rehabilitation of the patients suffering from maxillary bone loss, on behalf of literature and histological analysis and dynamic evaluation. Materials and methods: The study is based on 52 clinical cases, in which patients suffer from different degrees of maxillary atrophies, defects and deformations. The patients were treated using different procedures: autogenous, synthetic orcombined autogenous/synthetic bone grafting. Bone samples were taken from 4 of the patientsinvolved in the study, for histological analysis. Results: The study looked for the analysis of the resorbtion rate for each of the two grafts. We were able to evaluate only the resorbtion rate of the augmented autogenous bone. Dynamic clinical evaluation associated with mathematic calculus was made, coming to a result that resorbtion can grow up till 50% of the total volume of the reconstructed site. The resorbtion rate of the augmented alloplastic grafts, clinically was impossible to evaluate, because of the changes in volume that occur once the grafts are being placed in the receiving site. As an alternative analysis of the question above, bone samples were taken from patients, for further histological analysis. The histological results - microscopic images at the operational site in a time frame of 4 months, 7 months and 7 years show structures composed of synthetized new bone, medullary spaces and residual alloplastic biomaterial in a different quantity, depending on the range of time elapsed since the surgical procedure was performed. Conclusion: In order to delimit the ideal bone substitute for each situation, the bone substitute must be selected based on factors like: systemic health of patients, the elected surgical procedure, the osteogenic potential of the host residual bone, the morphology of the defects, etc.