ARGON-LASER ORAL SAFETY PARAMETERS FOR TEETH

Argon lasers have been reported to prevent or reduce demineralization of enamel in extracted teeth and to polymerize dental composites (usin g 25-100 J/cm2). Prior to clinical trials on caries prevention and cur ing composites, safety parameters for intraoral use of the argon laser need to be established. This study was conducted to determine the ena mel damage, pulp temperature changes, and associated pulpal tissue dam age following irradiation at various argon laser energy levels using 1 .6-6.0 watts, approximately 1 and 2 mm diameter beam for 0.2-5.0 secon ds. To evaluate pulpal damage, selected dogs' teeth were irradiated in vivo, extracted 7 days postlasing, fixed, decalcified, sectioned, sta ined, and read for pulpal damage. Pulp temperature and enamel damage t ests utilized extracted dog and human teeth. Temperature probes were i nserted in the pulp chambers and temperature changes recorded as ename l surface was lased. Enamel surface damage was evaluated by visual and microscope examination. Results showed that histologic pulpal damage occurred at > 600 j/CM2 . Temperature changes were < 6-degrees-F in hu man teeth with approximately 900 j/cm2 . No enamel damage was observed at these energy densities. At energy densities needed for proposed us es, no apparent damage would be expected to pulp or enamel. (C) 1993 W iley-Liss, Inc.