Curing lights are used primarily in the dental industry, where they are used in fillings, sealants, and adhesives for various dental procedures. Other versions of the curing light can be seen in use in manufacturing, where rapid and even curing can be an important part of the manufacturing process. A number of companies produce curing lights which have been custom designed for particular applications, ranging from electronics to dentistry.

In the dental field, a dental curing light can use ultraviolet or visible light, depending on what it is designed for. Both dentist and patient need to wear eye protection to limit damage to the retina for even the 20 seconds to a minute that the light is in use during rapid curing, and the light needs to be well maintained so that it will work properly and effectively. It’s also important to use the right curing light for the right resin product; many lights are designed to handle a range of resins safety.

When dentists or any member of a dental team uses dental curing lights, protective eyewear or a shield to cover the light-curing unit (LCU) is a must. Ophthalmic research shows that short wavelength light like that commonly used in dental curing lights may contribute to premature aging of the eye’s retina and to senile macular degeneration.

Light with wavelengths of less than 500nm, also known as near ultraviolet or blue light, has been shown to cumulatively harm the eye’s retina and decrease the ability of the macular region of the retina to provide sharp vision. This light may also be connected to the formation of cataracts.

Resin-based restorations and dental sealants are cured by light in the 370nm to 470nm range. Reliable research shows that this area below the 500nm range can be harmful to vision. Therefore, the use of appropriate eye protection or a shield when operating a dental curing light is essential. Any protection should filter out the majority of light that is less than 500nm.

Studies have shown that looking away while curing frequently allows the curing light tip to drift slightly, causing inadequate amounts of energy to be delivered to the restoration. Curing lights in use today provide very intense blue light and very short cure times, so even a slight drift reduces the amount of energy delivered to the restoration by a significant percentage.