Effect of different ceramic materials and substructure designs on fracture resistance in anterior restorations

• Published in: The Journal of prosthetic dentistry 2022-05, Vol.127 (5), p.785-792
• Main Authors: Jo, Eun-Hye, Huh, Yoon-Hyuk, Ko, Kyung-Ho, Park, Chan-Jin, Cho, Lee-Ra
• Format: Article
• Language: English
• ISSN: 0022-3913; 1097-6841
• DOI: 10.1016/j.prosdent.2020.09.056

Materials have been developed to reduce the chipping of ceramic veneer and improve the esthetics of anterior ceramic veneered restorations. However, studies of the effects of material and substructure design on fracture resistance are sparse. The purpose of this in vitro study was to investigate the fracture resistance of metal-ceramic (MC), zirconia-feldspathic porcelain (ZC), and zirconia-lithium disilicate (ZL) anterior restorations and evaluate the effect of material and substructure design. After preparing and scanning artificial maxillary central incisor teeth, titanium abutments and restoration specimens (n=90) were fabricated. MC, ZC, and ZL materials were prepared with substructure designs A (two-third coverage of the palatal surface) and B (one-third coverage of the palatal surface). After cementation, the specimens were thermocycled (10 000 cycles, 5 and 55 °C). Fracture load measurements, failure mode analysis, energy dispersive X-ray spectroscopy (EDS), line scan analysis, fractography, finite element analysis (FEA), and Weibull analysis were performed. Two-way ANOVA was used to identify the effects of material and substructure design on fracture load. One-way ANOVA was used to identify significant differences of fracture load (α=.05). MC and ZL showed significantly higher fracture load than ZC (P