Phosphoric acid as a conditioning agent in the Gluma bonding system.

PURPOSE

To investigate the effect of phosphoric acid conditioning gels on compatibility with the Gluma dentin bonding system.

MATERIALS AND METHODS

Sheer bond strengths (BS), marginal performance in dentin cavities and microleakage resistance in mixed cavities were used as target parameters to determine the efficacy of Gluma/Pekafill on dentin pretreated with conditioners of 5, 10, 20 or 35% H3PO4 and different amounts of silica (0, 5 and 10%) after 15, 30 60 or 120-second treatment duration. The thicknesses of the hybrid layers were determined along the dentin cavity margin by light microscopy.

RESULTS

Neither the phosphoric acid concentration and the silica content nor the conditioning times tested had a significantly different effect on SBS or marginal performance (P > 0.05). There was no relationship between the hybrid layer thickness and the target parameters either. The SBS recorded on dentin were in the same order of magnitude as previously found on acid etched enamel (+/- 17 MPa). The marginal performance and microleakage results after thermocycling proved adequate dentin bonding and cavity sealing. Phosphoric acid etching of dentin is compatible with the gluma bonding system.