Evaluation of fracture resistance after dynamic loading of implant supported CAD/CAM monolithic crown restorations with two different adhesive cements

Nowadays, polymer infiltrated ceramics and zirconia reinforced glass ceramics are produced in monolithic structure by using CAD/CAM system and can resist the chewing forces in the molar region with the increase of material variety and durability. The aim of this study was to evaluate the fracture strength of aged implant supported polymer infiltrated ceramic and zirconia reinforced glass ceramic monolithic CAD/CAM restorations with different cementation processes. Forty implant analog (T44020 Tpure, NucleOSS, Izmir, Turkey) embedded in acrylic resin and titanium abutments (T44802 Tpure, NucleOSS) were linked to these analogs. Following digital impression with intraoral scanner Trios3 (3Shape A/S, Copenhagen, Denmark), maxillary second premolar tooth design was performed. Polymer infiltrated ceramic VITA Enamic (VITA Zahnfabrik, Bad Säckingen, Germany) and zirconia reinforced glass ceramic VITA Suprinity (VITA Zahnfabrik) were milled with CAM unit S1 (vhf camfacture AG, Ammerbuch, Germany). The crowns are cemented with 3M RelyX Ultimate + Singlebond Universal Adhesive (3M Dental Products Division, St. Paul, MN, USA) and Panavia SA Cement Plus + Clearfil Ceramic Primer (Kuraray Co., Osaka, Japan). The samples were examined in 4 groups named EP, ER, SP and SR (n=10). Then samples were subjected to 480000 cycles of dynamic loading in the chewing simulator (SD Mechatronic Chewing Simulator CS-4, Willytech, Munich, Germany) to provide thermomechanical aging. The fracture strength test was calculated with a universal tester (3345 Tester, Instron, Norwood, MA, USA). One-way ANOVA analysis was used to compare the normal distribution of data between groups (p ˂ 0.05). According to the results of the study, the mean fracture strength values were 892.3 ± 46.95 N for EP group, 867.5 ± 84.85 N for ER group, 944.5 ± 77.8 N for SP group and 949.5 ± 62.14 N for SR group. No statistically significant difference was observed between the crown materials and cements evaluated in the study in terms of fracture resistance. Keywords: CAD/CAM restoration, implant supported fixed prosthesis, zirconia reinforced glass ceramic, polymer infiltrated ceramic, adhesive cement, fracture strength