Materials Research | |
Effect of exposure time vs. irradiance on knoop hardness of dental composites | |
Américo Bortolazzo Correr1  Mário Alexandre Coelho Sinhoreti1  Lourenço Correr-sobrinho1  Rubens Nisie Tango1  Simonides Consani1  Luis Felipe Jochins Schneider1  | |
[1] ,UNICAMP Piracicaba School of Dentistry Piracicaba SP ,Brazil | |
关键词: composite resin; energy density; Knoop hardness; light curing; | |
DOI : 10.1590/S1516-14392006000300006 | |
来源: SciELO | |
【 摘 要 】
A comparison was made of the hardness of Z250 and Esthet-X composites light cured with different light sources. Cavities (3 mm diameter x 6 mm deep) were prepared in 240 bovine incisors. The composite was bulk inserted and light-cured using halogen light, LED or xenon plasma arc (PAC) with different irradiances and exposure times, maintaining the same energy density. The specimens were stored in an incubator at 37 °C for 24 hours prior to sectioning for hardness measurements. Three measurements were taken at each depth: surface, 1, 2, 3, 4 and 5 mm. The data were analyzed by ANOVA and Tukey's test (p < 0.05). No statistically significant differences were found for LED up to 2 mm, for PAC up to 3 mm, and for halogen light up to 5 mm. Photoactivation with intermediate power density and exposure time resulted in the highest Knoop hardness values.
【 授权许可】
CC BY
All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License
【 预 览 】
Files | Size | Format | View |
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RO202005130152236ZK.pdf | 390KB | download |