Effects of Whitening Toothpastes on the Surface Roughness of Contemporary Restorative Materials: A Profilometric Study

Objectives: This in-vitro study aimed to evaluate the effects of four commercially ava-ilable whitening and conventional toothpastes on the surface roughness of contemporary res-torative materials, including an alkasite, a nano-hybrid composite, a nano-hybrid flowable composite, an ormocer-based flowable material, and a zirconia-reinforced glass ionomer. Materials and Methods: A total of 225 specimens were prepared and subjected to standardized simulated tooth-brushing equivalent to one month of clinical use. Surface ro-ughness (Ra) values were measured before and after brushing using a contact profilometer. Non-parametric statistical tests (Wilcoxon, Kruskal–Wallis, Dunn with Bonferroni correction) were used to analyze changes within and between material–toothpaste combinations. Results: Significant differences in surface roughness were found among most mate-rial–toothpaste combinations (p < 0.05). Ormocer, flowable composites (NF0, NF2), and Zir-conomer (Z2, Z3) showed the greatest susceptibility to abrasion, while NF3–NF4, A3–A4, and several nanohybrid subgroups (N1–N3–N4) demonstrated similar resistance with no signifi-cant changes. Conclusion: These findings indicate that the abrasivity of toothpastes influences resto-rative materials in a highly material-dependent manner. Clinical toothpaste selection should therefore consider the type of restorative material present.