Assessing the durability of dental composites in GERD-like condition: a study of color stability and hardness

This study aimed to evaluate the impact of acid erosion and mechanical abrasion-mimicking conditions associated with gastroesophageal reflux disease (GERD)-on the color stability and surface hardness of five commercially available dental composite resins, including four bulk-fill and one flowable composite. Standardized disc-shaped specimens were fabricated from Filtek Bulk Fill (FTB), SureFil SDR (SDR), Tetric N-Ceram (TNC), Beautifil Bulk Restorative (BBR), and Dynamic Flow (DYF). Specimens underwent 24-hour acidic storage (pH 2.8) and brushing simulation (5000 cycles) in acidic medium. Color changes (ΔE₀₀) were measured using a spectrophotometer, and surface microhardness (Vickers Hardness) was evaluated before and after treatment. Data were analyzed using one-way ANOVA, independent t-tests, and linear regression. All composites exhibited varying degrees of color change and hardness reduction, with BBR and SDR showing the most pronounced degradation, while FTB demonstrated the highest resistance. Composites with hydrophobic monomers (e.g., Bis-EMA) and high filler content exhibited improved resilience, whereas materials with hydrophilic matrices and lower filler loadings were more susceptible to deterioration Acid erosion and brushing significantly affect the aesthetic and mechanical properties of dental composites. Material composition-particularly polymer matrix type and filler matrix integration-plays a critical role in determining resistance to oral stressors. These findings underscore the importance of tailored material selection for patients with conditions like GERD and support the need for further development of durable restorative materials.