JOURNAL OF PROSTHETIC DENTISTRY THE

Vol. 102 No. 3      September - 2009

ISSN: 0022-3913      UBIC: 171

RESUMEN

Statement of problem. Vital tooth bleaching may affect properties of dental cements used for fixed prostheses. Purpose. The purpose of this study was to examine the effect of a combined in-office and at-home bleaching regimen on changes in surface roughness and depth loss of a variety of commercially available dental cements. Material and methods. Five cement classifications were tested: glass ionomer, resin-modified glass ionomer, resin, self-adhesive resin cement, and zinc phosphate. Cements were placed in multiple wells in plastic blocks. After setting, the surface profile of each block was determined, and average roughness and vertical height of cement surface from the specimen holder were recorded. Blocks were water stored (control) or subjected to n-office and at-home bleaching (n=1 2). Surfaces were rescanned and pre- and posttest parameter changes were calculated. Statistical analysis consisted of Mann-Whitney-Wilcoxon Rank Sum and Student t tests applied to control and bleaching parameter changes within the same cements. A family-wise alpha of.05 was maintained by using a Bonferroni-adjusted level of significance preset to .01 per test. Results. Zinc phosphate showed the only significant depth increase (P=.004) from bleaching: 0.9 ±0.7 µm deeper than the water-control group. Only resin-modified glass ionomer showed a significant (P=.004) increase n roughness from bleaching; values increased by 0.05 ±0.03 µm over the water-control group. Conclusions. In-office and at-home bleaching significantly increased depth loss of zinc phosphate and increased resin modified glass ionomer roughness. However, the absolute values of differences observed, as compared to the water only control, were considered to be clinically insignificant. (J Prosthet Dent 2009;1 02:148-154)

| Volver |