Investigation of the coloring effects of different ground-based coffee types on composite resin materials

Aim:  The aim of the study is to investigate the effect of different ground coffee types on the color change on nanohybrid and bulk fill composites. Methodology: A total of 80 disc-shaped samples were made from 2 types of A2 resin with nanohybrid (Tetric N Ceram Ivoclar Vivadent, Schaan, Liechtenstein) and bulk fill (Filtek Bulk Fill, 3M ESPE, St. Paul, MN, USA) structure with the help of 5 mm diameter and 8 mm thickness Teflon molds in this study. All samples were finished and polished with 4-stage (thick, medium, fine, superfine) polishing discs (Sof-lex, 3M ESPE, St. Paul, MN, USA) and kept at 37 °C for 24 hours. The samples, whose initial color measurements were made by spectrophotometer (VitaEasyShade, Vita ZahnFabrik, Bad Sackingen, Germany), were divided into subgroups for the control group and 4 types of ground-based coffee beverages including filter coffee, Turkish coffee, espresso, and Mırra (n=8). Distilled water used as control. Prepared coffees were added to the microcentrifuge tubes and refreshed daily during the 14-day exposure period. ΔE values were calculated for each material. The statistical analyses of the present study were performed using one-way analysis of variance and Tukey multiple comparisons (p=0.05). Results: There was no significant color change for both nanofill and bulk-fill composite groups in the control group samples (p>0.05). Filter coffee was found the most colorant coffee type on both composites (p<0.05). Among the coffee types, Mırra caused the least coloration in both composites. Conclusion: The consumption of two or more cups of coffee per day, especially filter coffee, can cause color changes on both conventional and bulk-fill composites, and it should be considered an important factor causing aesthetic problems in dental restorations.