الفهرس 
LED light curing unitOnly 14 pages are availabe for public view
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Abstract
Adequate luting agent polymerization is necessary to achieve high mechanical properties of the resin cement and consequently, an adequate bond to the root canal walls. However, as light intensity for light polymerization systems is reduced with increasing distance from the light source tip. The apical areas of post preparation in the root canal continue to represent a challenge in terms of the bonding protocol. As a result, there are additional difficulties with regard to the insertion and light-curing of adhesive restorative systems. Halogen bulbs used in conventional curing units are referred to as incandescent lights. Their spectrum of radiation is continuous over the visible range, with radiation intensity increasing considerably toward the red end of the spectrum. Due to the selective absorption characteristics of the commonly used photoinitiator, 98% of this radiation does not contribute to polymerization and must be filtered to avoid heating the irradiated objects and/or blinding the operator. In contrast, light emitting diodes (LED) convert electricity into light more efficiently, thereby, producing less heat. LED technology eliminates the need for filters and may reduce heat generation to the extent that cooling fans may not be required or need only be of low capacity.