Comparing Bone Graft Success, Implant Survival Rate, and Marginal Bone Loss: A Retrospective Study on Materials and Influential Factors.

Abstract

This retrospective study aimed to evaluate success rate of guided bone regeneration (GBR) bone grafting and investigate survival rate of implants, as well as degree of marginal bone loss (MBL) around implants. This study was carried out between January 2007 and December 2016 on treatment outcomes of patients with implants which used various graft materials, including autograft, allograft, and xenograft. The bone graft success rate and implant survival rate were recorded. The influence of confounding factors such as patient characteristics, bone graft properties, and implant conditions was considered. Moreover, MBL up to 3 years after implant installation was evaluated in periapical radiographs. In mean follow-up 70 months (range 3-10 years), overall success rate of bone graft (n=80) was 100% and overall survival rate of implant (n=107) was 97.2% (autograft and allograft 100%, and xenograft 92.9%, respectively; P=.03). The 3-year MBL were similar among bone grafts (autograft 0.84±0.48mm, allograft 0.73±0.42mm and xenograft 1.01±0.59mm, respectively; P=.14). Posterior mandibular location had a significant influence on implant survival (P=.003). Regarding MBL, patients aged >60 years (P=.03), patients with both diabetes and hypertension (P=.02), patients who did not receive adjunctive membrane use (P=.04), patients with <6 months of loading (P<.001) and patients with screw-retained crowns (P=.008) were significantly associated. Our data substantiated that implant rehabilitation with GBR using autograft and allograft provide the most predictable results. With xenograft, aforementioned factors should be carefully considered to enhance long-term clinical outcomes.