DEPTH OF CURE OF A FLOWABLE BULK FILL RESIN COMPOSITE WITH XYLITOL ADDITION
composite resin; fluid bulk fill; xylitol; depth of cure; microhardness.
Objective: To evaluate the depth of cure of the Tetric® N-Flow Bulk Fill composite resin with xylitol addition at different concentrations and thicknesses. Methodology: The Tetric® N-Flow Bulk Fill resin was mixed with xylitol concentrations (0% [Control], 2.5%, and 5% w/w). Cylindrical samples (n=3) were made in a mold with diameters of 5 mm and thicknesses of 1 mm, 2 mm, 3 mm, and 4 mm, photoactivated for 10 s, and stored at 37º C for 24 h. The specimens were subjected to Vickers microhardness testing, and the depth of cure was obtained through the bottom/top ratio. Non-parametric Kruskal-Wallis tests were used to compare different thicknesses at the same concentration and different concentrations at the same thickness (p<0.05) using BioEstat 5.3 software. Results: There was no statistically significant difference between different thicknesses at the same concentration, as well as between different concentrations at the same thickness (p=1.0). All specimens showed adequate depth of cure (hardness ratio ≥80%), except for the samples with 4 mm thickness containing 2.5% and 5% xylitol, which showed an average hardness ratio of 78% and 76%, respectively. Conclusion: Under the conditions of this study, it can be concluded that the addition of xylitol to a bulk fill flow resin can affect the depth of cure at 4 mm.