Damage to dental composite restorations following exposure to CO2 laser radiation.

Damage to tooth structure is a major hazard in the use of infrared lasers for oral surgical procedures. While the effects of laser exposure on dental enamel and dentine are well characterized, there are no data on the effects of laser exposure on dental composite materials, which are widely used in tooth-colored restorations. This study examined surface changes in several dental composites exposed to CO2 laser radiation for 200 msec. Surface changes, such as ablation, combustion, and melting, occurred even at relatively low power densities (340 W/cm2), with greater effects occurring in composites than in "compomers" (glass iomomer-composite mixtures). These findings indicate that nonmetallic dental restorations are prone to damage from inadvertent laser exposure. Clinicians must be aware of this hazard and employ measures to protect both natural tooth structure and restorations when performing intraoral laser surgery.