Objectives: This study aimed to determine the correlation between gloss and roughness in low-viscosity bulk fill composite resins. Materials and methods: The study had an experimental, analytical, prospective, and cross-sectional design, with a sample of 60 blocks of low-viscosity resins distributed into three groups of 20 units each: Group 1—3M Filtek Bulk Fill Flow (FBF), Group 2—Opus Bulk Fill Flow APS (OBF), Group 3—Opalis Flow (OF) (Control).
Gloss and roughness were measured using a gloss meter and a contact roughness meter. In the descriptive analysis, measures of central tendency and dispersion were calculated. The normality of the data was evaluated using the Shapiro-Wilk test. For the comparison of roughness between resins, the ANOVA test was applied, and for gloss, the Kruskal-Wallis test was applied, both with Tukey and Dwass-Steel-Critchlow-Figner post-hoc tests, respectively.
The relationship between variables was measured using Pearson and Spearman correlations. The data were processed using the SPSS statistical package, considering a significance level of 0.05. Results: The FBF resin had the highest average roughness, while OF had the lowest value; in addition, OF had the highest gloss values.
On the other hand, there was a statistically significant high negative correlation between roughness and gloss (p