Methodological Quality of Systematic Reviews Relating to Performance of All-Ceramic Implant Abutments, Frameworks, and Restorations

Purpose: To assess the methodological quality of published systematic reviews relating to all ceramic implant frameworks, abutments and restorations.

Materials And Methods: Published systematic reviews relating to all ceramic implant restorations for single tooth and multiple teeth replacements were retrieved to assess their methodological qualities. Sixteen systematic reviews were included for methodological quality assessment by two independent assessors using AMSTAR-2 critical appraisal tool. Inter-rater agreement was assessed using the weighted Cohen's Kappa statistic.

Results: Most systematic reviews included randomized clinical trials and nonrandomized studies of intervention. The majority of included systematic reviews (15 out of 16) scored critically low on quality with more than one critical flaw when assessed using the AMSTAR-2 tool. Most systematic reviews assessed lacked analysis of the effects of the risk of bias and heterogeneity of the included studies. The inter-rater agreement of the independent assessors was substantial (0.63).

Conclusions: Confidence in the evidence presented in these systematic reviews was undermined by their tendency to overlook the effect of risk of bias and heterogeneity in evidence synthesis.