Chuchai Anunmanaชูชัย อนันต์มานะAnusavice, Kenneth J.Mecholsky, Jr., John J.Mahidol University. Faculty of Dentistry. Department of Prosthodontics2015-11-212016-12-132015-11-212016-12-132010-02Anunmana C, Anusavice KJ, Mecholsky JJ Jr. Interfacial toughness of bilayer dental ceramics based on a short-bar, chevron-notch test. Dent Mater. 2010 Feb;26(2):111-7.https://repository.li.mahidol.ac.th/handle/20.500.14594/1011Objective—The objective of this study was to test the null hypothesis that the interfacial toughness of each of two types of bonded core-veneer bilayer ceramics is not significantly different from the apparent fracture toughness of the control monolithic glass veneer. Methods—T-shaped short bars of a lithia-disilicate glass-ceramic core (LC) and yttria-stabilized polycrystalline zirconia core ceramic (ZC) were prepared according to the manufacturer's recommendations. V-shaped notches were prepared by using 25-μm-thick palladium foil, leaving the chevron notch area exposed, and the bars were veneered with a thermally compatible glass veneer (LC/GV and ZC/GV). Additionally, we also bonded the glass veneer to itself as a control group (GV/ GV). Specimens were kept in distilled water for 30 days before testing in tension. Eight glass veneer bars were prepared for the analysis of fracture toughness test using the indentation-strength technique. Results—The mean interfacial toughness of the LC/GV group was 0.69 [0.11] MPa·m1/2, and did not significantly differ from that of the GV/GV control group, 0.74 (0.17) MPa·m1/2 (p > 0.05). However, the difference between the mean interfacial toughness of the ZC/GV group, 0.13 (0.07) MPa·m1/2, and the LC/GV and the GV/GV groups was statistically significant (p<0.05). Significance—For bilayer all-ceramic restorations with high-strength core materials, the veneering ceramics are the weakest link in the design of the structure. Since all-ceramic restorations often fail from chipping of veneer layers or crack initiation at the interface, the protective effects of thermal mismatch stresses oral prosthesis design should be investigated.engMahidol UniversityAll-ceramicBilayerChevron notchInterfacial toughnessZirconiaOpen Access articleArticleAcademy of Dental MaterialsMahidol University10.1016/j.dental.2009.09.003