Marginal adaptation of laboratory composite resin and ceramic restorations

Objectives: The aim of this study was to compare in vitro, the marginal adaptation of restorations constructed with the indirect restorative materials feldspathic ceramic (Noritake) and two second generation laboratory composite resins (Artglass and Targis). The marginal gap of the samples was microscopically analyzed at mesial, distal and lingual faces of restorations. Methods: A maxillary premolar was prepared to receive an onlay restoration with lingual cusp coverage. Thirty NiCr metal alloy copies were made from the prepared tooth and divided into three groups of ten, as follow: group l) Noritake, group ll) Artglass; group lll) Targis. The restorations were positioned in the metal copies and examined in a microscope at 40X magnification, connected to a computer. Images were captured by a software Microsoft VidCap 32 and marginal gaps thickness measured on restoration/metal copies interface through a distance cursor (software Imagelab 2000). Results: The means (µm) were: group l) mesial 64,50 (+- 38,26), lingual 47,50 (+- 35,69) and distal 53,00 (+- 29,36); group ll) mesial 56,00 (+- 25,03), lingual 35,50 (+- 25,65) and distal 56,00 (+- 19,55); group lll) mesial 69,50 (+- 9,56), lingual 53,00 (+- 20,44) and distal 55,50 (+- 29,29). The results of analysis of variance (ANOVA) indicated that there were no differences among the materials. The results of Tukey statistical test (5%) showed that there were statistical differences among faces studied. Conclusions: There were no statistical differences among marginal adaptation of materials. (Noritake, Artglass and Targis). Mesial face had greater gap significantly than the lingual one.