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.
Firoozmand
Leily M
LM
Department of Restorative Dentistry, São José dos Campos School of Dentistry, São Paulo State University (UNESP), Brazil. leilyfiroozmand@hotmail.com
Pagani
Clóvis
C
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