PENGARUH PERENDAMAN LARUTAN KOPI ROBUSTA TERHADAP KEKASARAN PERMUKAAN RESIN KOMPOSIT HIBRID

Background: Hybrid composite resin is a restorative material that has a filler size ranging from 0.4 to 1.0 m which has the property of absorbing liquid like robusta coffee. Robusta coffee contains acids that can cause surface roughness in hybrid composite resins. The purpose of this study was to determine the effect of Robusta coffee immersion on the surface roughness of the hybrid composite resin. Methods: This type of research is an experimental laboratory with a pre-post test design. The research sample amounted to 27 which were made in the form of a cylinder mold (10 mm x 4 mm). Each sample was immersed in distilled water for 24 hours and then tested for surface roughness. Group A was immersed in robusta coffee solution for 3 days. Group B was immersed in robusta coffee solution for 5 days. Group C was immersed in robusta coffee solution for 7 days. Then, the surface roughness of the sample was measured using the surface roughness measurement (Surfcorder SE 1700) and the results were using paired t-test and One Way Anova. Results: The results of the paired t-test showed p-value=0.000 which means that there was a significant difference between the pre-test and post-test scores. The results of the One Way Anova test showed p-value=0.039, which means that there was a significant difference between the sample groups. Conclusion: There was an effect of robusta coffee immersion on the surface roughness of the composite resin.