The Effect of Time Intervals on Bond Strength of Two Different Glass Silicate Materials Bonded to Resin Composite Using Self-etch Adhesives

Aims: Both Biodentine and (GIC) are often utilized as a lining or base material under the restorations of the resin composite as a substitute for the dentin. Waiting for the setting time of these materials (15 min. for Biodentine and 7 min. for GIC) can lead to complications. The use of an unset case for both materials with light-curing is recommended. However, moisture contamination throughout the setting could result in dissolution, and alteration of their physical characteristics which may be solved by using a self-etching adhesive system. So, the objective of this study is to compare and evaluate the bond strength of resin composite to underlying Biodentine and GIC in different interval times (before and after setting). Materials and Methods: 40 acrylic blocks that contain a central hole with a height of 2mm and a diameter of 5mm have been prepared and categorized into four groups, each of them containing 10 samples based upon the material that has been utilized as Group A Biodentine after setting, Group B immediate Biodentine, Group C chemical cure glass-ionomer cement (GIC) after setting and group D immediate GIC. The resin composite of 4.0mm diameter and 2.0mm height has been bonded afterward to every one of the samples, with the use of a universal adhesive. The analysis of the shear bond strength (SBS) has been carried out at a 0.5mm/min crosshead speed. Statistical Analysis: the statistical analysis has been carried out with the least significant difference (LSD) and one-way analysis of variance (ANOVA) tests were P>0.050 (Non-significant), P<0.050 (significant), P<0.001 (highly significant) using Statistical Package for the Social Sciences (SPSS) v. 20. Result: No significant differences have been found in the shear bond strength mean value between set Biodentine group (4.21 Mpa) and the non-set Biodentine group (2.7 Mpa), p>o.o5. Regarding the GIC group, the set GIC group was showing no significant differences from the non- set GIC group, in which the shear bond strength values were (13.36 and 11.22 Mpa) respectively (p>o.o5). Conclusion: The time intervals (set and non-set cases) have no significant differences for both Biodentine and GIC regarding the shear bond strength with light-curing composite using the self–etch bond.