Objectives: Several anatomical and histological limitations can complicate implant placement, angulated implant positioning appeared to compensate these limitations. However several studies suggested a higher rate of marginal bone loss and implant failure regarding tilted implants in comparison with conventional implant. Therefore this umbrella review aims to summarize and analyze all the evidence available concerning marginal bone loss and implant failure between tilted and axial implants.
Methods: An electronic literature search was conducted, without any language restrictions and only systematic reviews with meta-analysis or meta-analysis studies were included. The outcomes assessed in this review were implant failure and marginal bone loss in mm. Relative risks (RRs) and the differences of the mean (MD) were calculated with 95% confidence intervals (CIs) regarding implant failure and marginal bone loss respectively.
Results: in total 8 studies were included, based on the short-term results, a non-significant mean difference (MD=0.00; 95% Cl; -0.01-0.02; p-value = 0.75) was recorded between tilted and axial implants supporting full-arch dentures, meanwhile a significant mean difference was recorded on a 3 years and long term follow-up reached (MD= 0.08 95% Cl = 0.05-0.11; p value<0.00001)) and (MD= 0.18; 95% Cl= 0.15-0.20; p value< 0.00001) respectively, and an insignificant difference was observed between tilted and axial implants regarding implant failure (RR=1.02; 95% Cl=0.85-1.23; p value= 0.81) Conclusion: this review based on high and moderated quality studies with low risk of bias demonstrated no significant outcome was observed between tilted implants supporting full-arch or fixed partial denture and axial implants regarding implant failure.
Keywords: Tilted implant; Axial implant; Dental implant; Marginal bone loss; Implant failure.