[The shear strength of dentin-bonding agents under intrapulpal pressure and temperature change. An in-vitro study]

This in-vitro study reports on a modified method for testing shear bond strength of dentin bonding agents (DBA's). For a better imitation of the surface of vital human dentin, all DBA's used in this investigation (12 commercially available and one experimental) were tested with dentin under intrapulpal pressure (19.6 cm/36 cm H2O) and exposed to thermal cycling (x1500, 5 degrees C/55 degrees C). In group A the bonding agent was light cured before the application of the composite resin. In group B the bonding agent and the composite resin were light cured at the same time. The difference between the modified testing method and a commonly used method (application of the DBA onto a dry dentinal surface, water storage at 37 degrees C for 24 h) was significant (p < 0.001, ANOVA two way). The shear bond strengths recorded with our method were generally lower than formerly published results. A.R.T. Bond and Experimental had the best average results in both testing groups. Superbond C&B bond strength had to be interpreted separately.