Which is true concerning light emitting diode (LED) polymerization lights?

The correct choice is that light emitting diode (LED) polymerization lights cure materials with camphoroquinone photoinitiators. This is accurate because camphoroquinone is a commonly used photoinitiator in dental materials such as composites and bonding agents. It is activated by light in the blue spectrum, specifically around 450 nm, which is precisely where the output of many LED curing lights is concentrated.

While the other options present some relevant information, they do not apply specifically to the functioning of LED polymerization lights. For instance, while the spectral output of blue LEDs generally falls within the ranges mentioned, the effective curing wavelength for many dental materials tends to be optimized around 450 nm, making this detail significant but not definitive for curing mechanisms. The need for filters to prevent eye injury is less pertinent, as many LED devices are designed with safety features minimizing eye exposure risk. Lastly, while pulpal irritation from heat can be a concern with some curing lights, it is not uniquely or significantly associated with LED lights compared to other curing methods. This makes choice A the most accurate representation of the working principles of LED polymerization lights.