Journal of Dental Research, Vol 71, 410-413, Copyright © 1992 by International & American Associations for Dental Research Online Journals
The influence of polymerization shrinkage of resin cements on bonding to metal
C. W. Verzijden, A. J. Feilzer, N. H. Creugers and C. L. Davidson
TRIKON, Department of Oral Function and Prosthetic Dentistry, Dental School, University of Nijmegen, The Netherlands.
During the setting of a resin composite cement (RCC) used as an adhesive
between a resin-bonded bridge and tooth structure, the adhesion may be
disrupted by the development of shrinkage stress. The aim of this study was
to investigate the influence of the shrinkage stress of three different
RCCs on their adhesive and cohesive qualities when bonded to metal surfaces
in a rigid set-up. Two opposing parallel NiCr discs (Wiron 77) were mounted
in a tensilometer at a mutual distance of 200 microns and cemented with
Panavia Ex, Clearfil F2, or Microfill Pontic C. The alloy surfaces were
treated by either electrolytic etching, sand-blasting, silane-coating, or
tin-plating. During setting, the discs were kept at their original mutual
distance to simulate the extreme clinical situation of "complete" rigidity,
where the casting and the tooth cannot move toward each other. The
developing shrinkage stress was recorded continuously. During setting, the
adhesive strength of the RCCs to silane-coated surfaces was always higher
than their early cohesive strength. Electrolytically-etched surfaces as
well as sand-blasted surfaces showed, in almost all cases, adhesive
failure. The tin-plated samples showed mainly adhesive failure at the
metal/resin interface. The highest bond strength values were found for
silane-coated surfaces in combination with Clearfil F2.
