Influence of the curing method on the post-polymerization shrinkage stress of a composite resin
J. appl. oral sci
; 16(4): 266-270, July-Aug. 2008. ilus, tab
Article
em En
| LILACS
| ID: lil-486494
Biblioteca responsável:
BR28.1
ABSTRACT
The aim of this study was to evaluate the effect of different curing methods on the stress generated by the polymerization shrinkage of a restorative composite in two moments immediately after light exposure and after 5 min. Photoactivation was performed using two different light sources (1) xenon plasma arc (PAC) light (1,500 mW/cm2 - 3s) and (2) a quartz-tungsten-halogen (QTH) light with three light-curing regimens continuous exposure (40 s at 800 mW/cm2 - CL); soft-start (10 s at 150 mW/cm2 and 30 s at 800 mW/cm2 - SS) and intermittent light [cycles of 4 s (2 s with light on at 600 mW/cm2 and 2 s of light off), for 80s - IL]. The composite resin was applied between two 5-mm diameter metallic rods, mounted in a servohydraulic machine. The maximum stress was recorded immediately after light exposure (FF) and after 5 min (5F). The results were submitted to ANOVA and Tukey's test (5 percent). For each method, the results obtained in FF and 5F were, respectively CL (3.58 and 4.46 MPa); SS (2.99 and 4.36 MPa); IL (3.11 and 4.32 MPa) and PAC (0.72 and 3.27 MPa). The stress generated by the polymerization shrinkage during light exposure can be associated with the photoactivation method used. A significant increase in the stress level was observed during the post-curing period up to 5 min, for all evaluated methods.
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LILACS
Assunto principal:
Resinas Compostas
/
Cimentos de Resina
/
Análise do Estresse Dentário
/
Cura Luminosa de Adesivos Dentários
Idioma:
En
Revista:
J. appl. oral sci
Assunto da revista:
ODONTOLOGIA
Ano de publicação:
2008
Tipo de documento:
Article