Objectives: Shear bond strength of indirect composite to superficial dentin using three different resin cements and three curing lights with (T) and without thermal cycling (NT).
Methods: Cements used were Maxcem Elite/Self Adhesive Cement (MAX,Kerr), Panavia F2.0/Dual Cure (PAN,Kuraray) and RelyX ARC Adhesive Resin/Dual Cure (ARC,3MESPE) as the control. Two LED lights, FlashLite Magna (Discus Dental) and Valo (Ultradent) were compared to a standard quartz-tungsten-halogen, Optilux 501(Kerr). Samples were thermocycled for 500 cycles at 5-55°C. Extracted human teeth were sectioned, embedded in acrylic, ground to expose superficial dentin, and polished by 320-grit sandpaper. Premise (Kerr) indirect composite discs (4X3mm) were fabricated under pressurized nitrogen. Bonding surface of discs were sandblasted with 20-micron AlO2. Samples were divided into 18 groups (n=8). Cements were applied and cured according to the manufacturers' instructions. Shear bond testing was performed with an Instron machine at 0.5 mm/min following 24 hours 37°C storage. The data were analyzed using ANOVA and Tukey post hoc test at the 0.05 level of significance.
Results: Means and standard deviations of shear bond strengths (MPa) are displayed below:
Cement | Thermal Cycling | Optilux | Magna | Valo |
MAX | T | 3.90±1.9 | 4.84±3.8 | 4.86±2.3 |
ARC | T | 14.42±6.2 | 11.35±1.6 | 10.11±4.3 |
PAN | T | 11.68±5.6 | 13.23±6.6 | 9.82±5.3 |
MAX | NT | 6.01±3.1 | 5.02±2.2 | 5.50±3.8 |
ARC | NT | 12.12±4.6 | 13.04±5.1 | 9.25±4.3 |
PAN | NT | 11.85±5.6 | 10.78±6.5 | 15.92±5 |
Conclusions: There was no significant difference in shear bond strength among the lights (p>.05) or by thermal cycling (p>.05). However, there was a significant difference among the cements with MaxCem showing significantly lower bond strength compared to Rely-X and Panavia (p<.001). Supported in part by Kuraray, Kerr, 3MESPE, UTHSC Houston Dental Branch Research Office.