Is it important to use a radiometer with an LED light-curing unit?

Periodic evaluation of LED light performance with a radiometer is recommended. Typically, LED chips do not fail instantaneously, but have reduced output with prolonged use. There is no clinically relevant difference between radiometers for LED and QTH units, and absolute values from radiometers cannot be used to predict the potential for curing. Tip diameter can also greatly affect measurements. Use of these devices should be restricted to evaluating operating performance over time of a specified curing light/light guide combination.