RESUMO
OBJECTIVE: To evaluate strength of bi-layer alumina/Y-TZP specimens, compared with 3-point bending test and to estimate the reliability of MSP testing used in dental ceramics. METHODS: The single-layer/bi-layer alumina/Y-TZP specimens were produced by the clinical methods. Strength of these specimens was determined by MSP testing and 3-point bending test respectively. Fractured pieces of each bi-layer specimen were collected and studied with optical microscope and SEM. RESULTS: The MSP fracture strength was lower than bending strength in all the specimens. The strength of single-layer Y-TZP was the highest and the strength of bi-layer samples was lower than that of the single-layer samples respectively. Delamination and interface destruction were found in bi-layer alumina specimens, and not in bi-layer Y-TZP specimens. CONCLUSION: MSP testing is a convenient and feasible method to evaluate mechanical properties of dental ceramics.