Comparison of the bond strength of laser-sintered and cast base metal dental alloys to porcelain.
OBJECTIVE
The purpose of this study was to compare shear bond strengths of cast Ni-Cr and Co-Cr alloys and the laser-sintered Co-Cr alloy to dental porcelain.


METHODS
Dental porcelain was applied on two cast and one laser-sintered base metal alloy. Ten specimens were prepared for each group for bond strength comparison. ANOVA followed by Tukey HSD multiple comparison test (alpha=0.05) was used for statistical analysis. Fractured specimens were observed with a stereomicroscope to classify the type of failure after shear bond testing.


RESULTS
While the mean shear bond strength was highest for the cast Ni-Cr metal-ceramic specimens (81.6+/-14.6 MPa), the bond strength was not significantly different (P>0.05) from that for the cast Co-Cr metal-ceramic specimens (72.9+/-14.3 MPa) and the laser-sintered Co-Cr metal-ceramic specimens (67.0+/-14.9 MPa). All metal-ceramic specimens prepared from cast Ni-Cr and Co-Cr alloys exhibit a mixed mode of cohesive and adhesive failure, whereas five of the metal-ceramic specimens prepared from the laser-sintered Co-Cr alloy exhibited the mixed failure mode and five specimens exhibited adhesive failure in the porcelain.


CONCLUSIONS
The new laser-sintering technique for Co-Cr alloy appears promising for dental applications, but additional studies of properties of the laser-sintered alloy and fit of castings prepared by this new technique are needed before its acceptance into dental laboratory practice.


CONCLUSIONS
Laser sintering of Co-Cr alloy seems to be an alternative technique to conventional casting of dental alloys for porcelain fused to metal restorations.
Akova
Tolga
T
Department of Prosthodontics, Faculty of Dentistry, Cukurova University 01330 Balcali, Adana, Turkey. akovat@cu.edu.tr
Ucar
Yurdanur
Y
Tukay
Alper
A
Balkaya
Mehmet Cudi
MC
Brantley
William A
WA
D000268:Adhesiveness; D000537:Aluminum Oxide / Q000737:chemistry; D002858:Chromium Alloys / Q000737:chemistry*; D001840:Dental Bonding; D003735:Dental Casting Technique; D045662:Dental Etching; D003776:Dental Porcelain / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D007834:Lasers; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties
D002858:Chromium Alloys; D016876:Metal Ceramic Alloys; D003776:Dental Porcelain; D000537:Aluminum Oxide