Shear bond strength of a ceramic to Co-Cr alloys.
BACKGROUND
Different combinations of Co-Cr alloys bonded to ceramic have been used in dentistry; however, the bond strength of ceramic to metal can vary because of different compositions of these alloys.


OBJECTIVE
The purpose of this study was to evaluate the shear bond strength of a dental ceramic to 5 commercially available Co-Cr alloys.


METHODS
Five Co-Cr alloys (IPS d.SIGN 20, IPS d.SIGN 30, Remanium 2000, Heranium P, and Wirobond C) were tested and compared to a control group of an Au-Pd alloy (Olympia). Specimen disks, 5 mm high and 4 mm in diameter, were fabricated with the lost-wax technique. Sixty specimens were prepared using opaque and dentin ceramics (VITA Omega 900), veneered, 4 mm high and 4 mm in diameter, over the metal specimens (n=10). The shear bond strength test was performed in a universal testing machine with a crosshead speed of 0.5 mm/min. After shear bond testing, fracture surfaces were evaluated in a stereomicroscope under x25 magnification. Ultimate shear bond strength (MPa) data were analyzed with 1-way ANOVA and the Tukey HSD test (alpha =.05).


RESULTS
The mean (SD) bond strengths (MPa) were: 61.4 (7.8) for Olympia; 94.0 (18.9) for IPS 20; 96.8 (10.2) for IPS 30; 75.1 (12.4) for Remanium; 71.2 (14.3) for Heranium P; and 63.2 (10.9) for Wirobond C. Mean bond strengths for IPS 20 and IPS 30 were not significantly different, but were significantly (P<.001) higher than mean bond strengths for the other 4 alloys, which were not significantly different from each other.


CONCLUSIONS
Bond strength of a dental ceramic to a Co-Cr alloy is dependent on the alloy composition.
Joias
Renato Morales
RM
Department of Dental Sculpture, Occlusion, and Prosthodontics, Methodist University of Sao Paulo, Sao Bernardo do Campo, Sao Paulo, Brazil.
Tango
Rubens Nisie
RN
Junho de Araujo
Jose Eduardo
JE
Junho de Araujo
Maria Amelia
MA
Ferreira Anzaloni Saavedra
Guilherme de Siqueira
Gde S
Paes-Junior
Tarcisio Jose de Arruda
TJ
Kimpara
Estevao Tomomitsu
ET
D002516:Ceramics / Q000737:chemistry*; D002858:Chromium Alloys / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D006047:Gold Alloys / Q000737:chemistry*; D007854:Lead / Q000737:chemistry; D008422:Materials Testing / Q000295:instrumentation / Q000379:methods; D033081:Shear Strength; D013499:Surface Properties
D002858:Chromium Alloys; D003722:Dental Alloys; D006047:Gold Alloys; D007854:Lead