Background: Restorative dentistry increasingly demands materials that combine mechanical durability, esthetic performance, and biological compatibility. Composite resins and ceramic materials are widely used for posterior restorations, their comparative effectiveness remains an area of clinical significance. Objective: To compare the fracture resistance, wear behaviour, marginal sealing ability, and colour stability of nanohybrid composite resin and lithium disilicate ceramic inlay restorations under simulated intraoral conditions. Materials and Methods: 32 extracted human molars were divided into two groups (n=16): composite resin (Filtek Z350 XT) and ceramic inlays (IPS e.max CAD). Standardized Class I cavities were restored accordingly. Specimens were subjected to thermomechanical aging, including 10,000 thermal cycles and 100,000 chewing cycles. Fracture resistance, wear volume, microleakage, and colour stability (ΔE) were assessed using a universal testing machine, profilometer, stereomicroscopy, and spectrophotometry, respectively. Results: Ceramic inlays demonstrated significantly higher fracture resistance (1985.7 N vs. 1280.5 N, p < 0.001) and lower wear volume loss (0.017 mm³ vs. 0.042 mm³, p = 0.002). Microleakage was less pronounced in ceramics, with 87.5% scoring 0–1, while composites showed more dye penetration. Post-aging ΔE remained within acceptable limits for ceramics (2.4) but exceeded the threshold in composites (4.6). Conclusion: Lithium disilicate ceramics offer superior mechanical and esthetic properties compared to composite resins and are better suited for high-stress or esthetically sensitive restorations. Material selection should consider the specific clinical scenario and performance expectations.
Rayannavar et al. (Mon,) studied this question.