Application of blue laser LED for disinfection in COVID-19 era

Coronavirus (COVID-19) pandemic brought unprecedented attention to infection control protocols, raising public awareness and alarming healthcare professionals. Many protocols for infection control and air disinfection in the dental setting have been proposed and implemented, some of which include separation of the treatment area by physical barriers or single entry treatment rooms, the use of high-volume suctions and ventilation systems with incorporation of HEPA or photocatalytic air filters, non-thermal plasma, vaporized hydrogen peroxide, ozone, and ultraviolet (UV) light. Some of these methods such as direct UV radiation and gas/vapor disinfection can only be used between patients, or at the end of the day, and accidental exposure to both can have detrimental effects on health. Here, we propose the use of visible violet light for disinfection of the environment and inactivating airborne pathogens, such as coronavirus. This protocol entails isolation of the dental operatory area with barriers to include a certain amount of space around the dental chair, where aerosols and droplets are generated, and then, emission of violet light at 405 nm wavelength at 10 W by a blue laser LED in an area of 10 m2 for 20 minutes between treatment sessions. In contrast to UV emission or gas/vapor disinfection, violet light does not have adverse effects such as carcinogenicity, or damage to the skin, eyes, or lungs, and thus, can also be safely used in other buildings and public areas, as short exposure to its radiation is deemed to be harmless. Therefore, the use of violet light emission can be considered a safe, easy-to-implement, and fairly inexpensive disinfection method in COVID-19 era.