Long-term success rates of implants with guided bone regeneration or bone grafting

RUQUI ePOSTER CLINICAL RESEARCH – SURGERY

Background: In situation of insufficient alveolar bone, guided bone regeneration (GBR) or bone grafting is performed. The long-term success rate for this will need to be evaluated for the life of the implant.

Aim/Hypothesis: The purpose of this study was to determine the long-term survival and success rate after implant placement with guided bone regeneration (GBR) or bone grafting and to find the factors related with GBR that can affect the success rates of implants.

Materials and Methods: A total of 162 implants of 70 patients accompanied by GBR or bone grafting in the department of periodontology, Chonnam National University Dental Hospital from December 2008 to 2013 were enrolled. The survival rate of the implants and the success rate which classified by the ICOI were calculated by measuring the loss of the alveolar bone around the implant through standard intraoral radiographs. To investigate the correlation between the success rate and the factors related with GBR that can affect the success rate of implants, chi-square test and binominal logistic regression analysis were conducted.

Results: Up to 8 years follow-up, 13 out of 162 implants failed, resulting in 92.0% survival. Of the 149 implants, 126 implant showed less than 2 mm of marginal bone loss, showing a success rate of 77.8%. Bone resorption amounts around implants was -0.90 ± 1.51 mm (-3.93 to 1.61 mm) in less than 3- year follow up (N = 15), 0.14 ± 1.54 mm (-5.33 to 6.76 mm) in 3-7 year follow up (N = 107) and 0.57 ± 1.43 mm (-3.23 to 3.03 mm) over 7 year follow-up (N = 27). It was observed that the bone resorption was increased and the success rate decreased over time. The chi-square analysis showed significance for the implant site (P = 0.003). In binominal logistic regression analysis, the success rate of implants placed in the maxillary posterior region (P = 0.004) was significantly lower. In addition, there were no significant differences according to gender, age, type of connection, smoking, diabetes, SPT, the severity of periodontitis, type of bone graft materials, and type of membranes.

Conclusions and Clinical Implications: Within our results, up to 8 years follow-up, the success rate was 77.8%, the success rate of implants with GBR or bone grafting in the maxillary posterior region was low.