Influence of bleaching treatment on flexural resistance of hybrid materials.
The aim of this study is to evaluate the flexural resistance of three types of restorative materials: compomer (Freedom), resin-modified glass-ionomer (Vitremer) and composite resin (Esthet-X), observing whether the application of bleaching agent can cause alterations of their flexural properties. Sixty samples were made using a 10 x 1 x 1 mm brass mold, and divided into three groups: G1- Freedom (SDI); G2- Vitremer (3M ESPE); G3- Esthet-X (Dentsply). On half of the samples of each group (10 samples) the bleaching treatment was applied and the other half used as control, was stored in distilled water at a temperature of 37 degrees C. Whiteness HP Maxx bleaching system was applied on the sample surface following the manufacturer's recommendations, simulating the bleaching treatment at the clinic. After this period, a flexural strength (three-point bending) test was conducted using (EMIC DL 1000) machine until the samples fractured. The data were submitted to ANOVA and Tukey tests. Of the restorative materials studied, G3-(87.24 +/- 31.40 MPa) presented the highest flexural strength, followed by G1-(61.67 +/- 21.32 MPa) and G2-(61.67 +/- 21.32 MPa). There was a statistical difference in flexural strength after the bleaching treatment. It was concluded that the use of a beaching agent can promote significant alteration of the flexural strength of these restorative materials.
Department of Restorative Dentistry, São José dos Campos School of Dentistry, São Paulo State University (UNESP), Brazil. leilyfiroozmand@hotmail.com
Leily M
LM
Firoozmand
Clóvis
C
Pagani
D020770:Compomers; D003188:Composite Resins; D001840:Dental Bonding; D003793:Dental Restoration, Permanent; D005899:Glass Ionomer Cements; D008422:Materials Testing; D014073:Tooth Bleaching
D020770:Compomers; D003188:Composite Resins; C466112:Esthet-X; C477332:Freedom Compomer; D005899:Glass Ionomer Cements; C084550:Vitremer