TENSILE BOND STRENGTHS OF DUAL-CURED CEMENTS BETWEEN A GLASS-CERAMIC AND ENAMEL

Statement of the problem. Dual-cured cements have been used with casta ble ceramic restorations, but the tensile bond strengths of these mate rials have not been thoroughly researched. Purpose of the study. This study compared the tensile bond strengths between Dicer castable ceram ics and enamel of four dual-cure cements: Twinlook, Optec Dual-Cure Lu ting Cement, Clearfil CR Inlay and Dual Cement. Material and methods. Truncated cones made of Dicor castable ceramics were cemented to ename l of freshly extracted anterior teeth with these four cements. Before testing, all specimens were immersed in water at 37 degrees C for 24 h ours, and thermocycled 1000 times in 5 degrees C and 55 degrees C wate r, with a dwell time of 30 seconds each. Tensile force was used to sep arate each specimen with the Instron universal testing machine. Result s. Clearfil CR Inlay cement exhibited the highest mean tensile bond st rength (18.4 MPa), followed by Dual (18.3 MPa), Twinlook (15.2 MPa), a nd Optec Dual-Cure luting (14.9 MPa) cements. One-way analysis of vari ance did not reveal any significant differences (p = 0.05) among group s. A majority of the fracture was adhesive at the ceramic and cement i nterface. Conclusion. All four dual-cured cements formed strong bonds between enamel and Dicer cement, ranging from 14.90 MPa to 18.35 MPa, and there was no statistically significant difference.