Shear bond strength of aesthetic materials bonded to Ni-Cr alloy.
OBJECTIVE
This study was undertaken to evaluate the shear bond strength of four materials used as aesthetic material bonded to Ni-Cr alloy.


METHODS
Sixty-eight alloy discs were prepared and divided equally into four groups, and received four treatments for veneering: conventional feldspathic porcelain (Noritake EX-3) and three light-cured prosthodontic composite resins (Artglass, Solidex and Targis). The aesthetic materials were applied after metal structure conditioning in accordance with the manufacturers' recommendations. The specimens were stored in distilled water at 37 degrees C for 7 days. A universal testing machine was used to measure the shear bond strength of the specimens at a cross head speed of 0.5 mm/min. Fractured specimens were examined by using both optical and scanning electron microscope.


RESULTS
The analysis of variance and Tukey's test showed that the strongest mean shear bond was obtained with Noritake EX-3 (mean shear bond strength 42.90+/-7.82 MPa). For composites, the highest mean shear bond strength was observed for Targis (12.30+/-1.57 MPa); followed by Solidex (11.94+/-1.04 MPa) and Artglass (10.04+/-0.75 MPa). Optical analysis of the fractured surfaces indicated that for Targis and Noritake EX-3 all failures were a mixture of both cohesive and adhesive patterns. As for Artglass and Solidex, the fractures were mainly adhesive in nature.


CONCLUSIONS
The Solidex system was equivalent to the Targis system in bond strength and exhibited greater strength than the Artglass system. The porcelain fused-to-metal showed considerably higher shear bond strength than the three metal-resin bonding techniques.
Faculdade de Odontologia de Araraquara-UNESP, Departamento de Materiais Odontológicos e Prótese, Rua Humaitá, 1680 Araraquara, São Paulo 14801-903, Brazil. almilhatti@hotmail.com
Hercules Jorge
HJ
Almilhatti
Eunice Teresinha
ET
Giampaolo
Carlos Eduardo
CE
Vergani
Ana Lúcia
AL
Machado
Ana Cláudia
AC
Pavarina
D002858:Chromium Alloys; D003188:Composite Resins; D001840:Dental Bonding; D003776:Dental Porcelain; D003799:Dental Stress Analysis; D008422:Materials Testing; D016876:Metal Ceramic Alloys; D009532:Nickel; D033081:Shear Strength
D002858:Chromium Alloys; D003188:Composite Resins; D016876:Metal Ceramic Alloys; D003776:Dental Porcelain; D009532:Nickel