Objective: This systematic review evaluates implant survival and the change in the width of the horizontal ridge following immediate implant placement with or without a regenerative procedure.
Materials and methods: An electronic search of MEDLINE, EMBASE, and the LILACS database of the Cochrane Central Register of controlled trials was performed, along with a manual search, up to April 2018. Randomized controlled trials (RCTs) and quasi-randomized controlled clinical trials (CCTs) with >10 subjects were eligible for this systematic review. A meta-analysis of the risk difference in implant failure between the regenerative and non-regenerative procedure groups was performed using a fixed-effect model. In addition, a meta-analysis of the change in alveolar bone width was conducted using a fixed-effect model.
Results: Seven studies (six RCTs and one CCT) were included. A meta-analysis of three studies found no statistically significant risk difference in implant failure between the regenerative procedure and non-regenerative procedure groups. A meta-analysis of four studies showed that horizontal shrinkage of the alveolar ridge in the site of immediate implant placement was statistically significantly lower with the regenerative procedure than without it (<1 year follow up studies: weighted mean difference (WMD) 0.75 mm, 95% confidence interval 0.41-1.09, p < .00001; ≥1 year follow up study: WMD 1.22, 95% confidence interval 0.52-1.91, p = .00006; total: WMD 0.84 mm, 95% confidence interval 0.53-1.14, p < .00001).
Conclusion: Within the study limitations, immediate implant placement with a regenerative procedure showed similar implant survival and less shrinkage of the ridge width than immediate implant placement without a regenerative procedure. Due to the high risk of bias and small sample sizes of the included studies, further clinical studies are warranted to draw definitive conclusions.
Keywords: Guided bone regeneration; bone graft; immediate implant; implant survival.