Abstract
OBJECTIVE: To evaluate the strength of different crown materials used in the rehabilitation of mandibular posterior regions and to compare their performance under realistic conditions. METHODS: A total of 90 crowns made from three materials-zirconia, lithium disilicate, and metal-ceramic-were tested using compressive load testing. Crowns were placed on standardized resin dies simulating mandibular molars and subjected to cyclic loading and fracture strength assessment. RESULTS: Zirconia crowns exhibited the highest fracture resistance, followed by metal-ceramic and lithium disilicate crowns. Statistically significant differences were observed between the groups (P < 0.05). CONCLUSIONS: Zirconia crowns offer superior strength, making them ideal for mandibular posterior rehabilitation. However, the choice of material should also consider aesthetic requirements and patient-specific factors.