Abstract
The study evaluated the surface roughness, Knoop hardness and weight loss of restorative composites after the samples were immersed in HCl, distilled water and pH-cycling solutions. Two mini filled hybrid restorative composites - Esthet X and Clearfil AP-X were used in this study. Eighteen standardized cylindrical specimens of each material were prepared. After polishing and storing in distilled water for 24 h, the initial weight, Knoop hardness and surface roughness were measured. Then the samples were immersed in the three solutions separately. After the storage of 3 days, 1 week and 2 weeks, the microhardness and the surface roughness of the samples were measured. The weights of the samples were measured after 2 weeks. After 2 weeks, Knoop hardness values of all of the two composites used in this experiment was changed significantly. And the weight loss of the two composites also had a significant difference.
