Research shows that sensitivity and bond failure often results from incomplete polymerization of the material. Polymerization is initiated by a high intensity light which if not maintained or updated will underperform.

Resin composites were better and the lights became stronger. The plasma light was introduced in 1998. It was a high-intensity light with a fluorescent bulb claiming to cure in 3 seconds. There were negative aspects to this light: high priced, actually cured in longer times than 3 seconds, and it was expensive to maintain. This brought about another light source technology.

Today we use the LED light. While the LED lights have been around since the 90's they weren't widely used until the frustrations of the plasma lights were unbearable. LED lights are continually being developed.

With all the buzz these days over LEDs (one estimate is that 90% of all new lights being purchased in the U.S. are LEDs), the old reliable halogen dental curing light seems destined for the archives. It has been castigated for being heavy, still tethered to the base unit with a cord, noisy due to its fan, and possessing old technology.

Protective Shields Most lights (but not all) come with different types of protective shields that fit over the end of the tip or mount on various locations of the tips. These shields are meant to protect our eyes from blue wavelength light being emitted by these devices. While these shields can be convenient and do not require any additional hands to hold them, they can also be cumbersome to use and difficult to switch from tip to tip. In addition, they are not universal in their protection.

For example, the larger shields may interfere with getting your light tip close to a second molar. In addition, they provide no protection when curing the linguals of anterior teeth. We recommend the use of handheld shields to protect your eyes from the light generated by these units.