Titanium core/bone morphogenetic protein composite materials used to repair alveolar bone defects after immediate implant placement / 中国组织工程研究

ABSTRACT

BACKGROUND:Now experimental and clinical research on suitable bone substitutes for alveolar bone defects after dental implantation is an issue of concern.OBJECTIVE:To study the therapeutic effect of titanium core/bone morphogenetic protein (BMP) composite material on alveolar bone defects after immediate implant placement.METHODS:Twenty-four New Zealand rabbits were randomly assigned into normal group (no intervention),experimental group or control group.Animal models of bone femoral greater trochanter defect were made in the experimental and control groups.Dental implant and titanium core/BMP composite material were implanted in the experimental group,while dental implant and titanium core were implanted in the control group.Percentage of CD4+,CD8+ T lymphocytes,natural killer cell activity and interleukin 2 level were detected at postoperative 4 weeks;bone mineral density and osteogenesis around the implant were detected at postoperative 16 weeks through X-ray and histological examinations.RESULTS AND CONCLUSION:X-ray results showed that the bone mineral density in the experimental group was significantly higher than that in the control group (P ＜ 0.05).Histological results showed that in the experimental group,different degrees of cell lysis around the composite,more bone cells and bone matrices were found,implant-bone osseointegration formed well,and red-dyed mature bone tissues were detective inside the implant.Compared with the experimental group,lower number of bone cells and fibrocytes were found in the control group.Additionally,the percentage of CD4+ and CD8+ T lymphocytes,natural killer cell activity and interleukin 2 level in the experimental group were significantly lower than those in the control group (P ＜ 0.05).To conclude,the titanium core/BMP composite material can effectively repair alveolar bone defects after immediate implant placement to guide the growth of bone cells.