Objectives: Comparing debonding time of three different ceramic materials lithium disilicate, ultra-translucent zirconia and hybrid-ceramic with dentin using Er, Cr:YSGG laser application.
Materials and methods: Thirty recently extracted human mandibular molars were selected for study. They were fixed in acrylic resin blocks and their buccal surfaces were ground to expose dentin to provide flat surface for bonding then stored in distilled water at room temperature. Three different ceramic materials used in this study, lithium disilicate glass ceramics, hybrid-ceramic, ultra-Translucent Zirconia. A total of thirty square shaped Samples 4x4mm and 1mm thickness resembling crowns prepared from CAD/CAM (computer aided design/computer aided manufacture) ceramic blocks of these ceramic materials, 10 samples for each material. Samples bonded to dentin using dual cure self-adhesive resin cement (TOTALCEM ITENA, France). Laser debonding of ceramic samples of all three materials using Er,Cr:YSGG laser (Waterlase by Biolase). Data were parametric and showed variance homogeneity, so they were analyzed using independent t-test. The significance level was set at p < 0.05 within all tests.
Results: Results showed that there was a significant difference between different groups (p < 0.001). The highest value was found in Vita Enamic samples (160.00±22.91) followed by BruxZir (21.57±5.26), while the lowest value was found in Emax samples (7.00±1.29).
Conclusions: The Ultra translucent zirconia and Lithium disilicate were deboned from dentin using Er,Cr:YSGG laser. Using laser for debonding Ultra translucent Zirconia consumses higher time than for Lithium disilicate. Destruction of hybrid ceramics when it was exposed to Er,Cr:YSGG laser to debond it from dentin.