Aykent, FilizKalkan, MustafaYücel, Münir TolgaÖzyeşil, Atilla Gökhan2020-03-262020-03-262006Özyeşil, A. G., Yücel, M. T., Kalkan, M., Aykent, F., (2006). Effect of Dentin Bonding and Ferrule Preparation on the Fracture Strength of Crowned Teeth Restored With Dowels and Amalgam Cores. Journal of Prosthetic Dentistry, 95(4), 297-301. Doi: 10.1016/j.prosdent.2006.02.0250022-39131097-6841https://dx.doi.org/10.1016/j.prosdent.2006.02.025https://hdl.handle.net/20.500.12395/20443Statement of problem. It is necessary to obtain an adequate bond at the core/dentin junction where the majority of failures occur. The effect of recently developed dentin bonding agents on the fracture resistance of endodontically treated teeth at the amalgam core/dentin junction is unclear. Purpose. The Purpose of this study, was to evaluate the effects of 2 dentin bonding agents and a ferrule preparation on the fracture resistance of crowned mandibular premolars incorporating prefabricated dowel and silver amalgam cores. Material and methods. Sixty extracted mandibular second premolars were divided into 6 groups of 10 each. The coronal portion of each tooth was removed at the cemento-enamel junction (CEJ) in the first 3 groups. In the other groups, teeth were sectioned 1 nun above the CEJ to create a ferrule. After root canal preparations, prefabricated dowels (ParaPost) were placed. The first group served as a control and was tested without application of bonding agents and without incorporation of a ferrule design. In the second and third groups, respectively, an autopolymerizing adhesive (Superbond D-Liner) and a dual-polymerizing adhesive (Panavia F) were applied to tooth surfaces before restorative procedures. For the fourth (ferrule) group, no bonding agent was applied, but a 1-mm ferrule preparation was used. In the fifth (ferrule+D-Liner) and sixth (ferrule+Panavia F) groups, respectively, autopolymerizing and dual-polymerizing bonding agents were used in conjunction with the ferrule preparation. After amalgam core fabrication, Ni-Cr full cast crowns for each group were prepared and cemented. All specimens were stored in water for I week and thermal cycled 1000 times between 5 degrees and 55 degrees C. A compressive shear load was applied at an angle of 135 degrees to the crown, and the maximum load at fracture (N) was recorded. The data were analyzed with 1-way ANOVA and Tukey Honestly Significant Difference tests (alpha=.05). Results. Significantly higher fracture strength values were demonstrated for the ferrule+Panavia F (652.5 N), ferrule+D-liner (649.1 N) and ferrule (592.4 N) groups, respectively, than for the other groups. The next highest fracture strength values were found for the D-Liner (485.0 N) and Panavia F (486.3 N) groups. The control group (376.6 N) demonstrated the lowest fracture strength in all test groups (P<.001). Conclusion. A ferrule preparation or a bonding agent designed for silver amalgam core-dentin bonding can each increase the fracture strength for teeth receiving cast crowns after endodontic therapy and dowel and amalgam core restorations.en10.1016/j.prosdent.2006.02.025info:eu-repo/semantics/openAccessArticle95429730116616127Q1WOS:000236861000006Q3