Abstract | Keywords | Fulltext | Export | TOC

Aims: To study the effect of different curing modes of Light emitting diodes (LED) curing unit on thedepth of cure (DOC) of composite resin with light and dark shades and compare the results withconventional curing method by the use of halogen curing light. Materials and Methods: A total of 40cylindrical composite resin samples (4mm diameter and 6mm height) were prepared, 20 of light shadeand 20 of dark shade. They were subjected to four curing modes (n=5 for each group): conventionalhalogen light, and three modes related to the LED light curing unit (LCU) which were: Fast (F); Ramped(R); and Pulsed (P). The samples were irradiated to the time required by the manufacturer for each curingmode, and a digital micrometer was used to measure the depth of cure according to scraping methoddescribed in ISO 4049:2000. Data were collected and analyzed for comparison. Results: No significantdifference was found in the DOC of composite irradiated by LED curing light for all of the three curingmodes or shade. However, the LED produced significantly greater depths of cure when compared withconventional halogen curing unit for both shades. The lighter shade was cured to a significantly greaterdepth than dark one when considering halogen LCU. Conclusions: All curing modes of the LED lightcan produce similar DOC regardless of composite shade when irradiated to the time recommended by themanufacturer. However, Curing with conventional halogen curing unit yielded the least DOC values forlight or dark shades when compared with LED units. Longer irradiation times are needed to cure darkshades by the use of halogen LCUs.

Curing depth --- light emitting diode --- resin composite