IADR Abstract Archives
Calcium and Phosphate ion Release From Experimental Remineralizing Dental Composites
Objectives: Develop new remineralizing composites that sustainably release calcium (Ca2+), phosphate (PO43-) ions and exhibit mechanical/physical properties suitable for Class V restorations. Evaluate Ca2+ and PO43- ion release, mechanical strength, and water sorption (Ws) of experimental dental composites, containing quaternary ammonium monomers (AM) and amorphous calcium phosphate (ACP) filler.
Methods: Four AMs, designated AMadh1, AMadh2, AMsil2, and MTADS, were incorporated at 3, 3, 9 and 8 mass %, respectively into a resin comprised of urethane dimethacrylate (UDMA) (50.91%), polyethylene glycol-extended UDMA (18.18%) and ethyl 2-(hydroxymethyl)acrylate (30.91%), designated UPE resin. These levels were previously determined to be unaffected by elution with alcohol; exclusion of AM served as the control. Camphorquinone (0.2%) and ethyl 4-(dimethylamino) benzoate (0.8%) were used as the photo-initiating system with ACP (25%) as the filler. A Triad2000 curing light was employed for sample polymerization. Composite samples (n=5) were stored in pH 7.4 saline solution at 37 °C for 168 days. Released Ca2+ and PO43- ions, composite biaxial flexural strength (BFS), and Ws were determined for all formulations.
Results: During the 168-day test, the UPE-ACP composite released 26.1±3.1 mmol of Ca2+ and 28.8±3.1 mmol of PO43-. The incorporation of AM monomers did not disrupt ion release from the UPE-AM formulations. After saline exposure, the BFS of composites containing no AM (72.7±9.9MPa), AMadh2 (85.6±8.6MPa), AMsil2 (77.8±4.4MPa), MTADS (82.0±9.1MPa) were not significantly (P>0.05) different. The BFS of AMadh1 (96.1±12.9MPa) composite was higher (P=0.008) than control. A significant (P<0.001) increase in Ws of AMadh2 (189.9 mg/mm3) and MTADS (190.3 mg/mm3) composites, relative to the control (158.8 mg/mm3), AMadh1 (166.7 mg/mm3), and AMsil2 (173.4 mg/mm3) composites, was observed.
Conclusions: Continuous ion release and physical properties of UPE-based experimental remineralizing dental composites demonstrated their future potential as Class V restorative materials.
Methods: Four AMs, designated AMadh1, AMadh2, AMsil2, and MTADS, were incorporated at 3, 3, 9 and 8 mass %, respectively into a resin comprised of urethane dimethacrylate (UDMA) (50.91%), polyethylene glycol-extended UDMA (18.18%) and ethyl 2-(hydroxymethyl)acrylate (30.91%), designated UPE resin. These levels were previously determined to be unaffected by elution with alcohol; exclusion of AM served as the control. Camphorquinone (0.2%) and ethyl 4-(dimethylamino) benzoate (0.8%) were used as the photo-initiating system with ACP (25%) as the filler. A Triad2000 curing light was employed for sample polymerization. Composite samples (n=5) were stored in pH 7.4 saline solution at 37 °C for 168 days. Released Ca2+ and PO43- ions, composite biaxial flexural strength (BFS), and Ws were determined for all formulations.
Results: During the 168-day test, the UPE-ACP composite released 26.1±3.1 mmol of Ca2+ and 28.8±3.1 mmol of PO43-. The incorporation of AM monomers did not disrupt ion release from the UPE-AM formulations. After saline exposure, the BFS of composites containing no AM (72.7±9.9MPa), AMadh2 (85.6±8.6MPa), AMsil2 (77.8±4.4MPa), MTADS (82.0±9.1MPa) were not significantly (P>0.05) different. The BFS of AMadh1 (96.1±12.9MPa) composite was higher (P=0.008) than control. A significant (P<0.001) increase in Ws of AMadh2 (189.9 mg/mm3) and MTADS (190.3 mg/mm3) composites, relative to the control (158.8 mg/mm3), AMadh1 (166.7 mg/mm3), and AMsil2 (173.4 mg/mm3) composites, was observed.
Conclusions: Continuous ion release and physical properties of UPE-based experimental remineralizing dental composites demonstrated their future potential as Class V restorative materials.