Resin-matrix ceramics for occlusal veneers: Effect of thickness on reliability and stress distribution.

Autor: Ruggiero MM; Department of Prosthodontics and Periodontology, University of Campinas - Piracicaba Dental School, Limeira Avenue, 901, Piracicaba, SP, 13414-903, Brazil., Soares Gomes R; Department of Prosthodontics and Periodontology, University of Campinas - Piracicaba Dental School, Limeira Avenue, 901, Piracicaba, SP, 13414-903, Brazil., Pedroso Bergamo ET; Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Dr. Octávio Pinheiro Brisolla Avenue, 9-75, Bauru, SP, 17012-901, Brazil., Freitas MIM; Department of Prosthodontics and Periodontology, University of Campinas - Piracicaba Dental School, Limeira Avenue, 901, Piracicaba, SP, 13414-903, Brazil., Bonfante EA; Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Dr. Octávio Pinheiro Brisolla Avenue, 9-75, Bauru, SP, 17012-901, Brazil., Del Bel Cury AA; Department of Prosthodontics and Periodontology, University of Campinas - Piracicaba Dental School, Limeira Avenue, 901, Piracicaba, SP, 13414-903, Brazil. Electronic address: delbelcury@gmail.com.
Jazyk: angličtina
Zdroj: Dental materials : official publication of the Academy of Dental Materials [Dent Mater] 2021 Mar; Vol. 37 (3), pp. e131-e139. Date of Electronic Publication: 2020 Dec 01.
DOI: 10.1016/j.dental.2020.11.002
Abstrakt: Objective: To evaluate the influence of resin-matrix ceramic material and thickness on reliability and stress distribution of occlusal veneers (OV).
Methods: One hundred and twenty-six OV of a mandibular first molar were milled using a CAD/CAM system and allocated according to materials (resin nanoceramic (RNC) or polymer-infiltrated ceramic network (PICN)) and thicknesses (0.5, 1.0 and 1.5 mm), totaling six groups (RNC0.5, RNC1, RNC1.5, PICN0.5, PICN1, and PICN1.5). Step-stress accelerated-life testing was performed (n = 21/group) with the load applied at the distobuccal cusp tip of the occlusal veneer until failure or suspension. The use level probability Weibull curves and reliability were calculated and plotted (90% CI). Finite element analysis evaluated the stress distribution according to maximum principal stress (σ max ) on the restoration and maximum shear stress (τ max ) on the cement layer.
Results: There was no difference in the probability of survival for the estimated missions among the groups, except at 600 N in which the results were significantly lower to PICN1.5 (6%) compared to RNC1 (55%) and RNC1.5 (60%). The σ max values were higher for PICN (31.85-48.63 MPa) than RNC (30.78-33.09 MPa) in the same thicknesses. In addition, 0.5 mm groups concentrated more stress in the restoration (33.09-48.63 MPa) than 1.0 mm (31.11-35.36 MPa) and 1.5 mm (30.78-31.85 MPa) groups in the same material.
Significance: Both resin-matrix ceramic materials seem up-and-coming restorative systems for occlusal veneers irrespective of the thicknesses as a consequence of the high reliability.
(Copyright © 2020 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE