The light radiated by the broad spectrum dental LCU used in this study may be potentially hazardous to the operator’s eyes. 1. When looking at the refected light from human teeth without magnifcation loupes, at 40 cm distance, the maximum permissible cumulative daily exposure time to light refected from the tooth was approximately 11 min (range 630 to 690 seconds). 2. All the loupes increased the weighted blue light irradiance received by the eye. 3. Although the radiant fux received by the eye was greater when magnifcation loupes were used, the surface area of the image was increased by the square of the magnifcation. Thus, the hazard was less and the maximum permissible cumulative daily exposure time to refected light from a plasma arc light curing unit increased to 16–28 min. 4. Lack of eye movement when using loupes may increase the damaging efects of the higher radiant exposure to the retina.

Dear all, may it is not light radiation itself that bear such responsibility of being the cause of cancer. It is the type and density of free radicals generated by light. In addition to that, any residual source of free radicals will for sure manifest post-curing during use. My Regards