caa a22 4500 475782321 CHVBK 20180406123648.0 cr unu---uuuuu 170329e20000601xx s 000 0 eng 10.1023/A:1008981907601 doi (NATIONALLICENCE)springer-10.1023/A:1008981907601 Correlation between light intensity and exposure time on the hardness of composite resin [Elektronische Daten] [L. Sobrinho, M. de Goes, S. Consani, M. Sinhoreti, J. Knowles] This study evaluated the correlation between light intensity emitted by the curing units and exposure time on the of degree polymerization of dental composites by measured Knoop hardness. Specimens with 5 mm diameter and 2 mm height were prepared in a copper mold, covered with a mylar strip and polymerized for 30 sec by curing units with 50, 130, 180, 220, 280 and 520 mW/cm2, respectively. The output for all units was measured using a Curing Radiometer (Demetron). Other specimens were polymerized for 45, 60, 75, 90, 105, 120, 135, 150, 165 and 180 sec utilizing units of 130, 220 and 280 mW/cm2. Knoop hardness values of the top and bottom surfaces were measured after 24 h. The results indicate that the curing units with higher light intensity presented improved values of Knoop hardness on the top and bottom regions. As expected, the top surface always presented improved Knoop hardness values in relation to the bottom, after exposure for 30 sec. The values obtained on the surface were statistically superior compared to the values on the bottom (p<0.05) for the intensity of 130, 220 and 280 mW/cm2 after 30, 45 and 60 sec of exposure. ©2000 Kluwer Academic Publishers Kluwer Academic Publishers, 2000 Sobrinho L. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut de Goes M. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut Consani S. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut Sinhoreti M. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut Knowles J. Department of Biomaterials, Eastman Dental Institute, 256 Gray's Inn Road, WC1X 8LD, London, UK aut Journal of Materials Science: Materials in Medicine Kluwer Academic Publishers 11/6(2000-06-01), 361-364 0957-4530 11:6<361 2000 11 10856 https://doi.org/10.1023/A:1008981907601 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1008981907601 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sobrinho L. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut NATIONALLICENCE 700 1- de Goes M. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut NATIONALLICENCE 700 1- Consani S. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut NATIONALLICENCE 700 1- Sinhoreti M. Department of Biomaterials, Piracicaba Dental School (UNICAMP), Avenida Limeira, 901, Piracicaba-SP, Post code 13414-900, Brazil aut NATIONALLICENCE 700 1- Knowles J. Department of Biomaterials, Eastman Dental Institute, 256 Gray's Inn Road, WC1X 8LD, London, UK aut NATIONALLICENCE 773 0- Journal of Materials Science: Materials in Medicine Kluwer Academic Publishers 11/6(2000-06-01), 361-364 0957-4530 11:6<361 2000 11 10856 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer