Effect of indenter material on reliability of all-ceramic crowns.

Effect of indenter material on reliability of all-ceramic crowns. J Mech Behav Biomed Mater. 2020 Aug;108:103831 Authors: Lorenzoni FC, Bonfante EA, Valverde GB, Coelho PG, Bonfante G, Thompson VP, Silva NRFA Abstract OBJECTIVES: Controversy exists about whether the elastic modulus (E) mismatch between the loading indenter and ceramic materials influences fatigue testing results. The research hypotheses were that for porcelain veneered Y-TZP crowns 1) A low modulus Steatite indenter (SB) leads to higher fatigue reliability compared to a high modulus tungsten carbide indenter (WC); 2) Different surface damage patterns are expected between low and high modulus indenters after sliding contact fatigue testing. All ceramic crowns will exhibit similar step-stress accelerated life testing (SSALT) contact fatigue reliability (hypothesis 1) and failure characteristics (hypothesis 2) when using high stiffness tungsten carbide (WC, E = 600 GPa) vs. enamel like steatite (SB, E = 90 GPa) indenters. METHODS: Manufacturer (3M Oral Care) prepared Y-TZP-veneered all-ceramic molar crowns were bonded to aged resin composite reproductions of a standard tooth preparation and subjected to mouth-motion SSALT fatigue (n = 18 per indenter type). Failure was defined either as initial inner cone crack (IC), or final fracture (FF) when porcelain fractured (chipping). Selected IC specimens that did not progress to FF were embedded in epoxy resin ...
Source: Journal of the Mechanical Behavior of Biomedical Materials - Category: Materials Science Authors: Tags: J Mech Behav Biomed Mater Source Type: research