Clinical Research Associates
Heat - A Negative Side-Effect of High Intensity
The higher the intensity of a light, the more energy is absorbed by the oral tissue that the light falls on. That energy raises the temperature and can cause pain and damage.
A convincing demonstration of this energy transfer can be made by holding a high intensity light about 1 mm from the back of your hand, then actuating the light and seeing how long it can be held there before pulling your hand away in pain.
Click here to go the the May-June '99 CRA Newsletter about heating due to lights.
High intensity lights (argon lasers, plasma arc lights, halogen lights with highly focussed outputs [turbo tips]) can all cause oral tissues to become dangerously hot. To combat the heat issue, curing light manufacturers use filters which reduce the wavelengths emitted, thereby reducing the total energy. They also caution users to shorten cure times. CRA data, however, show that these measures can lead to insufficient cure in some cases and with some resins.
Click here to go to the December '99 CRA Newsletter on light/resin incompatibilities