Third-generation vs a second-generation LED curing light: effect on Knoop microhardness.

Richard B T Price; Corey A Felix; Pantelis Andreou

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PubMed · 17052038

Third-generation vs a second-generation LED curing light: effect on Knoop microhardness.

Richard B T Price·Corey A Felix·Pantelis Andreou

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Abstract

Third-generation light-emitting diode (LED) curing lights use several different types of LEDs within the light to deliver a broader spectral output compared with the narrower spectral output of second-generation curing lights. This study determined the benefits of this broader spectral output. A third-generation LED curing light was modified so that the 4 peripheral LEDs, which provide the lower wavelengths, could be turned on or off, allowing the light to be used as a third- or a second-generation LED curing light. Twelve composites of A2 and lighter shades were packed into molds 2 mm deep with an internal diameter of 12 mm, and then irradiated for 20 seconds. A laboratory-grade spectroradiometer was used to ensure that all the specimens received the same irradiance and total energy (16.82 J/cm2) from the curing light in both the second- and third-generation modes. The results showed the benefits of using a broader spectrum third-generation LED curing light. This light produced composites that were as hard as when the narrower spectrum second-generation LED curing light was used (P < or = .01). In 7 of the 12 resin composites, the top surface was harder when the third-generation LED curing light was used (P < or = .01).

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Richard B T Price, Corey A Felix, Pantelis Andreou. 2006. Third-generation vs a second-generation LED curing light: effect on Knoop microhardness.. https://pubmed.ncbi.nlm.nih.gov/17052038/

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