Selective removal of residual composite from dental enamel surfaces using the third harmonic of a Q-switched Nd:YAG laser

Background and Objective: Conventional methods of residual composite removal after the debonding of orthodontic brackets involve the use of abrasives that damage the underlying enamel. The objective of this study was to demonstrate that 355-nm laser pulses with a pulse width of 10 ns are well suited for the removal of composite through selective laser ablation. Study Design/Materials and Methods: The residual composite remaining on the surface of extracted human third molars and bovine incisors was removed using multiple laser pulses from the third harmonic (355-nm) of a Q-switched Nd:YAG laser. Results: There is selective ablation of composite from the enamel surface without any discernable damage to the underlying enamel. Conclusion: This study demonstrates that 355-nm, 10 ns laser pulses can be used for the selective ablation of dental composite without thermal or mechanical damage to the underlying enamel. Lasers Surg. Med. 30:240-245, 2002. (C) 2002 Wiley-Liss, Inc.