Ability of a Polywave LED Light to Cure Five Composites

Objective: The ability of the polywave Bluephase LED curing light to cure five composites was compared to three other LED-curing lights.

Methods: The polywave Bluephase, Bluephase 16i, LEDemetron II and UltraLume 5 LED curing lights were all used for 10s to cure; Tetric Evoceram A2 and M shade, Filtek Supreme A2, Vit-l-escence A2, and Ælite LS Posterior A2 composites at distances of 4 and 8mm from the end of the light guide. The samples were then stored for 24 hours before 49 Knoop microhardness readings were made 0.5mm apart in 3x3mm grid at the top and bottom of the composites. A total of 240 samples were made in random order and 23,520 Knoop hardness readings were taken to determine the ability of the curing lights to cure the resin composites. Analyses were completed using PROC MIXED and PROC GLM statistical procedures using an α of 0.05.

Results: The polywave Bluephase light delivered a broad spectral output, the greatest energy density at both distances (15.5 and 10.5 J/cm²), and maintained the highest irradiance as the distance from the light guide increased. This light produced a uniformly hard surface across a 9mm² area on the surface of the composite. Overall, the polywave Bluephase light produced the hardest composite (p<0.01). Individual comparisons for each composite at both distances and at both top and bottom surfaces, showed that in every case the polywave Bluephase produced the hardest composite. The mean microhardness values achieved by each light on all the composites were compared and plotted as a percentage of the overall maximum hardness. The polywave Bluephase produced the maximum overall hardness(100%), UltraLume 5(80%), Bluephase 16i(78%), LEDemetron(76%).

Conclusion: For every composite and surface tested, the polywave Bluephase light produced the hardest, best-cured composite (p<0.05).

This study was supported by NSERC, Dalhousie University and Ivoclar-Vivadent.