Resinas compostas single-shade: uma revisão sistemática e um estudo laboratorial

Abstract

Direct resin composites can be a conservative treatment with high aesthetics. Aesthetics are influenced by its color and translucency properties. More esthetic results are obtained by materials that satisfactorily mimic dental structures. Material color selection remains a challenge due to its high technical sensitivity. With the aim of simplifying the technique, reducing clinical time and costs, single-shade composite resins appeared, which seek to adapt to all dental colors (A1 to D4). The objective of this work is to present the state of the art of single-shade resins, in addition to evaluating the influence of two depths (2 and 4 mm) on the color difference (ΔE00) and on color matching. Phase I of the study corresponded to a search in eight databases (Pubmed, Embase, Scopus, The Cochrane Library, Web of Sciences, BBO, LILACS, IBECS) up to February 2023, without date and language restrictions. In total, 5149 studies were identified, 45 were read in full, and 40 were included. Laboratory studies or clinical trials that evaluated single-shade composite resins were included. Reviews, case series or case reports were excluded. Most studies were laboratory experiments (37) and 3 clinical studies. In phase II, a laboratory test was carried out with 2-and-4 mm deep cylindrical cavities in acrylic molar teeth (n=10/group). Restorations were performed with 2 single-shade resins (OC: Omnichroma, Tokuyama; VU: Vittra APS Unique, FGM) and a multi-shade control resin (EO: Estelite Omega EA2, Tokuyama). ΔE00 was measured in the instrumental analysis, while color matching in the visual analysis. Two-way ANOVA and Tukey's post-test were used to assess the instrumental analysis, and Kruskal-Wallis and Tukey's post-test to assess the color matching of the visual analysis. The significance level was 5%. In phase I it was observed that the color matching can be influenced by the material composition, translucency, substrate color, size and depth of the restoration. Considering the CIEDE and CIELab predetermined color difference acceptability thresholds, in general, single-shade resins showed poor color matching ability. However, when compared to multi-shade resins, they would have a better color match for different shades of substrates. In phase II, the depth influenced the color difference only in the instrumental analysis. OC resin showed a similar color difference to EO at depths of 2 and 4 mm, while VU showed the best color matching results at both depths in the visual analysis.