|
Dicor has not been prescirbed routinely, in spite of many advantages, because of esthetic limitations by excessive translucency and external shading. In an attempt to solve these problems, the technique of veneering Dicor by aluminous porcelain has been used and recently Dicor Plus system was developed. The purpose of this study was to evaluate the compatibility between Dicor and several veneering procelains by measuring the shear bond strength and observing the failure mode and interface appearance with SEM. Total 55 Dicor disks (10.0mm diam. X 3.0mm thickness) were fabricated by lost was technique and divided into five groups of 11. Veneering porcelains such as Dicor Plus. Vitadue Alpha, Vitadur N, Vivodent, and ceramco II were built up over the center of the treatment Dicor surface using paper tube (5.0mm diam. X 4.0m height) and fired according to the manufactures; instructions. A representative sample from each group was completely embedded in epoxy resin and crossectioned, and remaining 50 samples were embedded in epoxy resin and crosssectioned, and remaining 50 samples were embedded in epoxyresin with the bonded area perpendicular to table base. The shear bond strengths were measured by applying the shear load parallel to Dicor surface close to the bonded area. Failure modes and interface appearances were observed using SEM at 15 and 1000 magnification respectively. @ES The obtained results were as follows: @EN 1. The mean shear bond strengths showed Dicor-Dicor Plus(10.53 mPa); Dicor-Vitadue Alpha(8.84 Mpa); Dicor-Vitadue N (7.37 Mpa); dicor-Vivodent (4.28 Mpa); Dicor-Ceramco II (0.89 Mpa). 2. The shear bond strength of Dicor-Ceramco II was significantly decreased compared with Dicor-Dicor Plus(p<0.01), but had no significant difference compared with Dicor-Vivodent (p>0.01). 3. The shear bond strengths of Dicor-Vitadur Alpha and Dicor-Vitadur N were not significantly different compared with Dicor-Dicor Plus(p>0.01). 4. SEM examination of bond failure modes revealed that Dicor-Dicor Pus, Dicor Vitadue Alpha, Dicor-Vitadur N exhibited cohesive failure within Dicor and Dicor-Vivodent exhibited adhesive failure. And Dicor-Ceramco II exhibited adhesive failure cohesive failure within Ceramco II together. 5. SEM examination of interfaces revealed that Dicor-Cicor Plus exhibited the most tight contact and Dicor-Vitadur Alpha, Dicor-vitadur N exhibited acceptible contacts. But Vivodent exhibited discontinous gap and Ceramco II exhibited large continuous gap
|