Which feature most directly contributes to an amalgam restoration's ability to resist occlusal forces?

• A. Margin adaptation
• B. Color match
• C. Adequate depth providing thickness
• D. Polishing quality

Answer: (C)

The key factor is having enough material bulk to withstand chewing forces. Amalgam gains its ability to resist occlusal loading from its thickness; when the restoration has adequate depth, the cross‑section provides strength and distributes stresses so it’s less likely to crack or fracture under bite forces. Margin adaptation, while important for sealing and preventing leakage, doesn’t directly increase the restoration’s resistance to occlusal stress. Color match is cosmetic, and polishing quality mainly affects wear and smoothness rather than bulk strength. Therefore, ensuring adequate depth providing thickness is the best way to enhance an amalgam’s resistance to occlusal forces.