RESPONSE OF ASSOCIATED ORAL SOFT-TISSUES WHEN EXPOSED TO ARGON-LASER DURING POLYMERIZATION OF DENTAL RESINS

Background and Objective: Polymerization of dental resins with Argon l aser produces restorations with improved physical properties when comp ared to conventional visible-light polymerization techniques. However, the possibility of damaging adjacent soft tissues has not been addres sed. Study Design/Materials and Methods: In this study, Argon laser (4 88/514 nm) was used for the polymerization of composite resins to dete rmine effects on the parakeratinized gingiva adjacent to both restored and unrestored teeth in six dogs, using 10-, 20-, and 30-second polym erization exposures. Results: Gingival tissues removed at 24 hours, 72 hours, or 5 days revealed desiccated, disrupted, hyalinized connectiv e tissue. Tissues exposed for 10 seconds showed minimal change. This m inimal degree of change was most evident at 72 hours and returned to n ormal limits at 5 days. The 20-second exposure produced alterations ev ident through all time periods. Tissues exposed for 30 seconds exhibit ed necrosis, severe disruption, and vessiculation, which was still unr esolved at 5 days. Conclusion: This study demonstrates that clinically relevant Argon laser exposure (10 seconds) of parakeratinized gingiva adjacent to teeth undergoing restoration does not cause lasting damag e. (C) 1997 Wiley-Liss, Inc.