Color stability and surface roughness of resin-ceramics with different surface treatments: A systematic review and meta-analysis of in vitro studies

Statement of problem: Surface treatments for resin-ceramics have been developed to obtain a smooth surface and improve color stability. However, a consensus on the best treatment for these materials is lacking. Purpose: The purpose of this systematic review and meta-analysis was to evaluate the color stability and roughness of glass‐ceramics versus resin‐ceramics with different surface treatments. Material and methods: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed, and the study was registered in the open science framework (OSF) for in vitro studies. The population, intervention, control, and outcome (PICO) question was “Is there a difference in color stability and roughness between resin-ceramic vs vitreous ceramics in different surface treatment protocols?” A literature search was performed in PubMed/MEDLINE, Embase, Web of Science, Scopus, Cochrane Library, and ProQuest databases up to January 2023. The Joanna Briggs Institute's critical assessment guidelines for quasi-experimental studies were used for quality assessment. The meta-analysis was based on the inverse variance (IV) method (α=.05). Results: A total of 18 laboratory studies were published between 2015 and 2022, with a total of 2160 specimens, all of which were analyzed qualitatively. The meta-analysis indicated significantly less optical alteration for lithium disilicate ceramics (P<.01; MD: 2.69; 95% CI: 2.00–3.39; I²=89%, P<.01), even when compared with resin-ceramics with polish or sealants (P<.01; MD: 2.45; 95% CI: 1.59–3.30; I²=87%, P<.01) and (P<.01; MD: 3.24; 95% CI: 2.02–4.47; I²=89%, P<.01), while there was no significant difference in surface roughness (P=.08; MD: −0.71; CI 95%: −1.52 to 0.09; I²=87%, P<.01) (P=.33; MD: −0.31; CI 95%: −0.94 to 0.32; I²=87%, P<.01), respectively. Conclusions: Resin-ceramics that have been polished or treated with sealants have lower color stability than glazed glass-ceramics; however, they are similar in terms of surface roughness.