Biological effect of the abutment material on the stability of peri-implant marginal bone levels: A systematic review and meta-analysis.

OBJECTIVES

The primary aim of this systematic review was to evaluate the available evidence on the effect of the abutment material on the stability and health of the peri-implant hard tissues.

METHODS

A protocol was developed to answer the following focused question: "Which is the effect of the abutment material on stability and health of the peri-implant hard tissues?" Randomized controlled trials (RCTs), controlled clinical trials (CCTs) or prospective case series (CS) with at least 6 months of follow-up were included, and meta-analyses were performed to compare abutment materials vs. titanium and to evaluate the impact of various abutment materials on bone changes (primary outcome), probing depth, plaque levels and peri-implant mucosal inflammation.

RESULTS

Twenty-nine publications from 33 investigations were included. Results from the meta-analyses demonstrated no significant differences between the different abutment materials when compared to titanium, in regard to the changes in marginal bone levels (MBLs) (n = 15; WMD = 0.034; 95% CI [-0.04, 0.10]; p < 0.339). The meta-analysis reported a significantly greater increase in bleeding on probing for titanium compared to zirconia abutments (n = 3; WMD = -26.96%; 95% CI [-45.00%, -8.92%]; p = 0.003). When evaluating the behaviour of each material different to titanium, there was a significant bone loss over time (n = 31; WMD = 0.261; 95% CI [0.18, 0.35]; p < 0.001) for all the individual materials except for titanium nitride.

CONCLUSIONS

This systematic review has shown that the abutment material had minimal impact on marginal bone levels when compared to the standard titanium.