Wearing of magnification loupes seems to be increasingly popular among medical and dental personnel to improve visibility of detail. In this paper, we investigated whether wearing magnification loupes during the light curing procedure would influence the time to reach the limit value for blue-light exposure to the eyes, compared to a situation in which no loupes were used. The emission of a broad-spectrum dental curing lamp was reflected off the surface of a human tooth model and passed through magnification loupes before it reached a spectrometer light detector, mimicking the operator’s eye. Three loupes with 2.5 × magnification and two loupes with 3.5 × magnification were included.
Using this experimental model, it turned out that the presence of magnification loupes did not decrease the time to reach the limit value compared to exposure of reflected blue light from curing lamps to the naked eye. Curing light exposure without loupes exceeded the daily limit value in about 10 minutes, thus necessitating eye protection. It is worth noting that the experimental model did not take into account that the operator’s eyes may be more fixed when wearing loupes, thereby suppressing normal eye movement, leading to increased light exposure of the pupil. Furthermore, loupes intended for dentistry can be equipped with a visible light source, and the blue-light content will add to the total light dose received by the eye. These factors may increase the cumulative blue-light exposure and contribute to increase the ocular hazard.
Price RB, Labrie D, Bruzell EM, Sliney DH, Strassler HE. The dental curing light: A potential health risk. J Occup Environ Hyg. 2016 Aug;13(8):639–646. doi: 10.1080/15459624.2016.1165822. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/27003737