Comparative Evaluation of Surface Roughness of Different Composite Restorative Materials after Thermocycling and Prolonged Immersion in Common Beverages Using Atomic Force Microscopy— In Vitro Study.

ABSTRACT: Background: Direct composite restorations face abrupt temperature changes, varying pH, and surface deterioration in the oral environment. Atomic force microscopy (AFM) provides visual and numerical data on surface roughness. Aim: This study evaluates and compares the surface roughness of composite restorative materials after simulating oral conditions. Materials and Methods: Three composite groups (n = 16 each) were tested. Group A: Microhybrid, Group B: Nanofilled, and Group C: Nanohybrid. Each group was divided into four subgroups (n = 4 each): distilled water (control), black coffee, Coca-Cola, and Red Bull. After thermocycling and immersion, surface roughness was measured using AFM. Results: Nanocomposites with uniform monomodal fillers showed the least surface disintegration and superior properties. Conclusion: Resin chemistry, including filler size and matrix composition, is crucial for composite properties and performance under function. [ABSTRACT FROM AUTHOR]