Portal de Periódicos da CAPES

Load-bearing capacity and the recommended thickness of dental monolithic zirconia single crowns

2014; Elsevier BV; Volume: 35; Linguagem: Inglês

10.1016/j.jmbbm.2014.03.014

1751-6161

Ting Sun, Shanyu Zhou, Renfa Lai, Ruoyu Liu, Shuyuan Ma, Zhiying Zhou, Longquan Shao,

Dental Research and COVID-19

The aim of this study was to evaluate the load bearing capacity and a reasonable thicknesss of dental monolithic zirconia crowns. Polymethyl methacrylate (PMMA) abutment tooth specimens were made by CAD/CAM technic. Monolithic zirconia crowns (MZC), monolithic lithium disilicate crowns (MLC), layered zirconia crowns (LZC) and metal ceramic crowns(MCC), of which the occlusal thickness was 1.5 mm were thereafter fabricated and cemented on the abutment tooth specimens. MCC with occlusal thicknesses of 0.6 mm, 0.8 mm, 1.00 mm, 1.2 mm were also made. All specimens underwent load-to-fracture test. Weibull parameters (σ0) and (m) were calculated. Fracture modes were also evaluated. The mean fracture load was 1863.16±116.81 for MLC, 2284.77±355.60 for MCC, 2308.0±510.94 for LZC, 4109.93±610.18 for MZC (1.5 mm), 3068.31±233.88 for MZC (1.2 mm), 2429.88±315.03 for MZC (1.0 mm), 1814.60±68.21 for MZC (0.8 mm) and 1308.38±111.38 for MZC (0.6 mm). The fracture load of MZC was significantly higher than MCC, LZC and MLC (P<0.05). The fracture loads for MCC with different thickness were significantly different (P 0.05). Monolithic zirconia crowns exhibit higher fracture loads than monolithic lithium disilicate crowns, layered zirconia crowns and metal ceramic crowns. The fracture resistance of monolithic zirconia crowns with a thickness of 1.0 mm can be equal to metal ceramic crowns. Doubling the monolithic zirconia core from 0.6 mm to 1.5 mm increases the fracture resistance of this restorative system threefold.