A comparison of 3 alloy surface treatments for resin-bonded prostheses.
OBJECTIVE
The most frequent cause of clinical failure of resin-bonded fixed partial dentures is a debonding at the metal-cement interface. The purpose of this in vitro study was to compare the tensile bond strengths of 3 different alloy-surface treatments when cemented to human enamel with a resin cement.


METHODS
Cylinders of a nickel-chromium-beryllium (Ni-Cr-Be) and a gold-palladium (Au-Pd) alloy were fabricated and assigned to different surface treatment groups as follows: Group 1: Ni-Cr-Be, chemically etched; Group 2: Au-Pd, airborne particle-abraded and tin-plated; and Group 3: Au-Pd, airborne particle-abraded and treated with the Alloy Primer (Kuraray Co, LTD, Osaka, Japan). The cylinders were bonded to the enamel surfaces of extracted, human third molars and stored in normal saline at 37 degrees C for 48 hours. The tensile bond strength of 21 specimens from each group was measured on a Universal Testing Machine (Instron, Canton, MA). Three failed specimens of each group were evaluated using scanning electron microscopy and energy dispersive spectroscopy.


RESULTS
Statistically significant differences (p <.05) were found between all 3 treatment groups. The mean tensile bond strengths (+/- the standard error of mean) recorded as follows: Group 1: 10.6 MPa (+/-1.3), Group 2: 0.9 MPa (+/-0.2), and Group 3: 13.4 MPa (+/-1.0). Specimens from groups 1 and 3 revealed a trend towards mixture of cohesive, within the resin cement, and adhesive failures at the metal-cement interface. Group 2 specimens exhibited primarily adhesive failures at the metal-cement interface.


CONCLUSIONS
The tensile bond strength of Au-Pd alloy specimens was significantly increased with the Alloy Primer.
Petrie
C S
CS
Department of Restorative Dentistry, University of Missouri-Kansas City, School of Dentistry, Kansas City, MO 64108, USA. petriec@umkc.edu
Eick
J D
JD
Williams
K
K
Spencer
P
P
D000134:Acid Etching, Dental; D000268:Adhesiveness; D000388:Air; D000537:Aluminum Oxide / Q000737:chemistry; D000704:Analysis of Variance; D002484:Cementation; D002858:Chromium Alloys / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry*; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure; D003799:Dental Stress Analysis / Q000295:instrumentation; D016379:Denture, Partial, Fixed, Resin-Bonded; D004577:Electron Probe Microanalysis; D004595:Electroplating; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D010165:Palladium / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D013223:Statistics as Topic; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014001:Tin / Q000737:chemistry
D002858:Chromium Alloys; D003722:Dental Alloys; D006047:Gold Alloys; D008689:Methacrylates; C093719:Panavia TPN-S; D010710:Phosphates; D019279:Resin Cements; C100646:Metal Primer; D010165:Palladium; D014001:Tin; D000537:Aluminum Oxide