Self-etching adhesives and postoperative sensitivity.

Purpose: To test the hypothesis that the prevention of postoperative sensitivity in resin-based composite restorations is better achieved with a self-etching/self-priming (SE/SP) dentin bonding system without lining than with an early generation total-etch (TE) bonding system.

Methods: Over a 4-year period, clinical follow-ups were conducted on patients who had received composite restorations. The depth of each cavity was categorized as being shallow, medium or deep, and an evaluation was made regarding the need for pulpal protection for each restoration.

Water absorption of poly(methyl methacrylate) containing 4-methacryloxyethyl trimellitic anhydride.

The amount of water absorption of poly(methyl methacrylate) (PMMA) containing 0, 1, 3 and 5 wt% of an adhesive monomer, 4-methacryloxyethyl trimellitic anhydride (4-META), was measured at 7 degrees C, 37 degrees C and 60 degrees C. After the water uptake reached equilibrium in specimens, they were desorbed to obtain a constant value and the absorption process was repeated. Mass changes in the second desorption were recorded for the storage temperatures of 37 degrees C and 60 degrees C.