PHOSPHORIC-ACID AS A CONDITIONING AGENT IN THE GLUMA BONDING SYSTEM

Purpose: To investigate the effect of phosphoric acid conditioning gel s on compatibility with the Gluma dentin bonding system. Materials and Methods: Shear bond strengths (SBS), marginal performance in dentin c avities and microleakage resistance in mixed cavities were used as tar get parameters to determine the efficacy of Gluma/Pekafill on dentin p retreated with conditioners of 5, 10, 20 or 35% H3PO4 and different am ounts of silica (0, 5 and 10%) after 15, 30, 60 or 120-second treatmen t duration. The thicknesses of the hybrid layers were determined along the dentin cavity margin by light microscopy, Results: Neither the ph osphoric acid concentration and the silica content nor the conditionin g 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 SBSs re corded o n dentin were in the same order of magnitude as previously found on ac id etched enamel (+/- 17 MPa). The marginal performance and microleaka ge results after thermocycling proved adequate dentin bonding and cavi ty sealing. Phosphoric acid etching of dentin is compatible with the G luma bonding system.