Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Polymerization stress, shrinkage and elastic modulus of current low-shrinkage restorative composites

Full text
Author(s):
Cidreira Boaro, Leticia Cristina [1] ; Goncalves, Flavia [1] ; Guimaraes, Thayse Costa [1] ; Ferracane, Jack Liborio [2] ; Versluis, Antheunis [3] ; Braga, Roberto Ruggiero [1]
Total Authors: 6
Affiliation:
[1] Univ Sao Paulo, Dept Dent Mat, BR-05508000 Sao Paulo - Brazil
[2] Oregon Hlth & Sci Univ, Dept Restorat Dent, Div Biomat & Biomech, Portland, OR 97201 - USA
[3] Univ Tennessee Hlth Sci Ctr, Dept Biosci Res, Coll Dent, Minneapolis, MN - USA
Total Affiliations: 3
Document type: Journal article
Source: Dental Materials; v. 26, n. 12, p. 1144-1150, DEC 2010.
Web of Science Citations: 121
Abstract

Objective. To compare currently available low-shrinkage composites with others regarding polymerization stress, volumetric shrinkage (total and post-gel), shrinkage rate and elastic modulus. Methods. Seven BisGMA-based composites (Durafill/DU, Filtek Z250/FZ, Heliomolar/HM, Aelite LS Posterior/AP, Point 4/P4, Filtek Supreme/SU, ELS/EL), a silorane-based (Filtek LS, LS), a urethane-based (Venus Diamond, VD) and one based on a dimethacrylate-derivative of dimer acid (N'Durance, ND) were tested. Polymerization stress was determined in 1-mm high specimens inserted between two PMMA rods attached to a universal testing machine. Total volumetric shrinkage was measured using a mercury dilatometer. Maximum shrinkage rate was used as a parameter of the reaction speed. Post-gel shrinkage was measured using strain-gages. Elastic modulus was obtained by three-point bending. Data were submitted to one-way ANOVA/Tukey test (p = 0.05), except for elastic modulus (Kruskal-Wallis). Results. Composites ranked differently for total and post-gel shrinkage. Among the materials considered as ``low-shrinkage{''} by the respective manufacturers, LS, EL and VD presented low post-gel shrinkage, while AP and ND presented relatively high values. Polymerization stress showed a strong correlation with post-gel shrinkage except for LS, which presented high stress. Elastic modulus and shrinkage rate showed weak relationships with polymerization stress. Significance. Not all low-shrinkage composites demonstrated reduced polymerization shrinkage. Also, in order to effectively reduce polymerization stress, a low post-gel shrinkage must be associated to a relatively low elastic modulus. (C) 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. (AU)