Shear Bond Strength of Self-Adhesive Cements to Enamel and Dentin

Objectives: The objective of this study was to assess the bonding performance of five commercially available and one experimental; self-adhesive cements to enamel and dentin after thermocycling compared to PanaviaF 2.0 a dual cured resin cement with self etching primer (control).

Method: Surfaces of 160 extracted teeth were wet ground with a series of abrasive disks to obtain 80 flat enamel and 80 dentin surfaces ending with180-grit SiC. Self-adhesive cements were manipulated following manufacturers' instructions and loaded in plastic tubes. The cement column in the plastic tube was cured under a constant weight for 20 seconds with visible light (Coltolux LED, 550mW/cm²⁾. Samples were incubated at 37⁰C for 24 hours and then thermocycled (5⁰-55⁰C) for 1000 cycles (15 seconds dwell time). The specimens were mounted in an Instron universal testing machine (model 5565) and loaded in shear to failure using a 1 mm/min crosshead speed. The bonding area of selected debonded specimens were examined under SEM.  Data were analyzed with ANOVA and Tukey/Kramer post hoc tests.

Results: Results are displayed below (Mean ± SD) in MPa (n=10).

	Panavia F 2.0	RelyX Unicem Clicker	G-Cem Capsule	Biscem	Maxcem	Multilink Sprint	Experimental Cement
Enamel	11.98 ±0.9	8.05 ±0.7	6.21 ±1.0	6.62 ±3.0	6.43 ±1.4	6.12 ±1.7	7.29 ±1.9
Dentin	10.26 ±1.3	11.34 ±1.5	10.4 ±1.2	5.69 ±1.1	6.60 ±1.3	6.57 ±2.2	7.15 ±1.3

Conclusions: Panavia F2 produced significantly great shear bond strengths to enamel than all other materials (p<.0001).  For dentin RelyX Unicem Clicker produced significantly higher bond strength compared to Biscem, Experimental, Sprint and Maxcem.  Bond strength differed by substrate (p<.0001).  Self adhesive cements provide greater bond strengths when bonding to dentin.  Supported in part by a grant from Kuraray.