Tribochemical silica-coating or alumina blasting for zirconia bonding? A systematic review of in vitro studies

Objective: The purpose of this systematic review was to compare the bond strength between zirconia and resin cements reported by when using tribochemical silica-coating or alumina blasting for the surface treatment of zirconia. Material and methods: A systematic search was conducted in the PubMed/Medline, Embase, Scopus, ISI Web of Science, and Latin American and Caribbean Health Sciences (LILACS) databases up to July 2023. Additionally, a grey literature search was performed on Google Scholar and Open Grey. All in vitro studies evaluating resin-mediated bond to zirconia blasted with silica-coated alumina particle (tribochemical silica-coating) compared to alumina particles (alumina blasting), using silane/phosphate-based primer or phosphate-based cement as chemical treatment were included. Selection of studies, data extraction, and risk of bias analysis were performed. Results: A total of 40 studies were included in the qualitative analysis. Without aging, 8 of the included studies reported higher bond strengths when zirconia was blasted with silica-coated alumina particles in comparison to alumina particles (p < 0.05). Nine studies did not report a significant difference in bond strength between surface treatments (p ≥ 0.05). After aging, most of the studies (n = 22) reported a higher average bond strength for tribochemical silica-coating/silane-based treatments in comparison to alumina blasting/zirconia primers (p < 0.05) while 17 studies showed no difference in bond strength values between the two surface treatments (p ≥ 0.05). The evidence was graded as moderate quality due to the medium risk of bias for most of included studies. Conclusion: Based on included studies, the findings indicated that tribochemical silica-coating/silane-based treatments are more effective than alumina blasting/zirconia primers in enhancing the bond strength to zirconia.