OBJECTIVES: This study evaluated the effectiveness of the diode-pumped solid state (DPSS) laser as a light source for light-curing dental resin composites. BACKGROUND DATA: A DPSS laser of 473 nm may be useful because of its match with the absorption peak of camphorquinone (CQ), the photoinitiator. MATERIALS AND METHODS: A DPSS laser (LAS) of 473 nm and a quartz-tungsten-halogen (QTH) light-curing unit (OP) were used as the light sources for light curing six different resin composites (four nanocomposites and two hybrid composites). Polymerization shrinkage and mass change (water sorption and solubility) were measured during and after light curing to determine the degree of polymerization. Mass change was evaluated by following the ISO 4049 standard. RESULTS: According to the evaluation, the specimens light cured using LAS showed similar maximum polymerization shrinkage (12.3∼18.1 μm for LAS; 13.2∼16.2 μm for OP) and water sorption (11.4∼24.1 μg/mm(3) for LAS; 11.3∼22.8 μg/ mm(3) for OP) to the cases light cured using OP. The specimens light cured using LAS showed a significantly higher solubility than the cases light cured using OP (2.4∼6.6 μg/ mm(3) for LAS; 0.8∼1.6 μg/ mm(3) for OP). However, the maximum water sorption and solubility obtained from the specimens were lower than the values permitted by the ISO 4049 standard. CONCLUSIONS: The results may suggest that the DPSS laser with an emission wavelength of 473 nm can be used as a light source for light-curing dental resin composites.
OBJECTIVES: This study evaluated the effectiveness of the diode-pumped solid state (DPSS) laser as a light source for light-curing dental resin composites. BACKGROUND DATA: A DPSS laser of 473 nm may be useful because of its match with the absorption peak of camphorquinone (CQ), the photoinitiator. MATERIALS AND METHODS: A DPSS laser (LAS) of 473 nm and a quartz-tungsten-halogen (QTH) light-curing unit (OP) were used as the light sources for light curing six different resin composites (four nanocomposites and two hybrid composites). Polymerization shrinkage and mass change (water sorption and solubility) were measured during and after light curing to determine the degree of polymerization. Mass change was evaluated by following the ISO 4049 standard. RESULTS: According to the evaluation, the specimens light cured using LAS showed similar maximum polymerization shrinkage (12.3∼18.1 μm for LAS; 13.2∼16.2 μm for OP) and water sorption (11.4∼24.1 μg/mm(3) for LAS; 11.3∼22.8 μg/ mm(3) for OP) to the cases light cured using OP. The specimens light cured using LAS showed a significantly higher solubility than the cases light cured using OP (2.4∼6.6 μg/ mm(3) for LAS; 0.8∼1.6 μg/ mm(3) for OP). However, the maximum water sorption and solubility obtained from the specimens were lower than the values permitted by the ISO 4049 standard. CONCLUSIONS: The results may suggest that the DPSS laser with an emission wavelength of 473 nm can be used as a light source for light-curing dental resin composites.
Authors: William Telford; Matilde Murga; Teresa Hawley; Robert Hawley; Beverly Packard; Akira Komoriya; Fred Haas; Charles Hubert Journal: Cytometry A Date: 2005-11 Impact factor: 4.355