Evaluation of effect of the use composite graft material (HA-TCP / COL) as an onlay graft material around dental implant on bone regeneration

With the development of implant surgery in recent years, the use of bone graft materials has become more important and more common in dentistry. Therefore, researchers have focused on the development of new bone graft materials. One of these graft materials is the three-dimensional composite graft (HA-TCP / Col) material. The inorganic phase of natural bone tissue is mostly formed by (Hydroxyapatite) HA, while the organic phase is formed by Type 1 collagen. There are studies in the literature on the successful results of three-dimensional composite graft materials produced to mimic this structure. As far as we know, there is no study on the use of composite graft material as an onlay graft around the dental implant. In this experimental study, the results of onlay use of composite graft around the implant were evaluated by comparing the results of the onlay application of autogenous bone ring and the results of the use of the composite graft in the socket. In this experimental study, 4 adult male sheep were used. Four standard bone defects 10 mm in diameter and 2 mm in depth were prepared for onlay groups and two standard bone defects 10 mm diameter and 6 mm in depth were created for socket group in pelvis of the sheep. A total of 6 (3.7 mm diameter 10 mm-long) implants were placed in each sheep. Autogenous ring block grafts and composite grafts were applied around the implants. All animals were sacrified after 12 weeks of healing period. The implants with surrounding bone defects were removed en bloc. Undecalcified sections were prepared for histomorphometric analysis. The data were analyzed statistically. As a result, compared with composite graft onlay usage, the autogenous graft group was found to be more successful in terms of bone implant contact and bone volume, but the results were not statistically significant. In addition, it has been determined that composite graft material does not make a statistically significant difference in bone implant contact rate and new bone volume in the use of onlay and socket around the implant. Key Words:Implant, composite graft, onlay graft, autogenous graft, histomorphometry