Curing lights are found in every dental practice today and are a necessary tool in the armamentariums of modern-day dental practices. Curing lights, like everything else in dentistry and the rest of the world, have evolved and changed over the years and there is a plethora of them still in use today. In this brief article, we will discuss and review how curing lights have evolved and where they are today.
Some of the original curing lights developed in the 1970s for dentistry-emitted UV light, but it was not long before dentistry moved away from this type of light due to its limitation in clinical settings (of course, nowadays we know the implications of UV light damage). Quartz halogen lights came along not long afterwards in the 1980s, when the focus became more on blue light and how we could cure resins better and have a greater depth of cure.
In the late 1990s, plasma ARC lights came along that cure resins in five seconds or less due to their high intensity nature. However, initial costs, heat generation and clinical concerns over fast curing times and how these lights worked kept them from gaining widespread popularity. Quartz halogen lights were a mainstay in dentistry for years and worked well, but they had limitations in depth of cure. Over time, the halogen bulbs degrade and the overall output decreases with time. This, in turn, ultimately leads to under-cured resins and premature failure.
Manufacturers continued to develop curing lights, and along came the newest addition to curing lights: LED (light emitting diode). LED lights are becoming mainstream in dentistry as well as life in general, from flashlights to light bulbs. Unfortunately, the first-generation LED lights were weak and the depth of cure was very limited, but this changed quickly when the newest, second generation of LED lights came along. Now, third generation LED lights have multiple wavelength peaks. Both second and third-generation lights have consistent and high outputs and work extremely well.
LED lights in dentistry have a lot of advantages over the older quartz halogen lights. For one, the light output is consistent, does not diminish over time, and the light output is higher along with a more focused blue wavelength that is needed for the photoinitiator in composite resins.
Because LED lights require a lot less energy to operate, many of the LED curing lights on the market today are lightweight, portable, cordless and battery-operated. The other great attribute of LED curing lights is that they generate significantly less heat in comparison to older curing lights.
Clinical studies suggest that LED curing lights today cure composite resin to a greater harness and to a greater depth of cure. So, if you have not looked at LED curing lights and have older quartz halogen lights in your office, you may want to consider something that will help you and your patient.
Jeff Lineberry, DDS, FAGD, FICOI, Accredited Member of the AACD and Visiting Faculty and Contributing author for Spear Education