Bacteriologic evaluation of the effect of Nd:YAG laser irradiation in experimental infected root canals

• Published in: Journal of endodontics Vol. 28; no. 4; p. 276
• Main Authors: Piccolomini, Raffaele, D'Arcangelo, Camillo, D'Ercole, Simonetta, Catamo, Giovanni, Schiaffino, Gianluigi, De Fazio, Pietro
• Format: Journal Article
• Language: English
• Published: United States 01-04-2002
• Subjects: Actinomyces - growth & development; Actinomyces - radiation effects; Aluminum Silicates; Chi-Square Distribution; Colony Count, Microbial; Dental Pulp Cavity - microbiology; Disinfectants - therapeutic use; Humans; Laser Therapy; Neodymium; Pseudomonas aeruginosa - growth & development; Pseudomonas aeruginosa - radiation effects; Root Canal Irrigants - therapeutic use; Root Canal Preparation - methods; Sodium Hypochlorite - therapeutic use; Statistics as Topic; Sterilization - methods; Yttrium
• ISSN: 0099-2399
• DOI: 10.1097/00004770-200204000-00004

The aim of this study was to evaluate the efficacy of the Pumped Diodium-Nd:YAG laser in sterilizing contaminated root canals. After hand instrumentation, 30 teeth were inoculated with Actinomyces naeslundii CH-12 and 30 teeth with Pseudomonas aeruginosa ATCC 27853 and incubated for 24 h. The teeth were divided into three subgroups: subgroup A received no treatment; subgroup B was irradiated with laser (5 Hz for 15 s or 10 Hz for 15 s); and subgroup C was irrigated with 5.25% NaOCl. The number of viable bacteria in each group was evaluated by using the surface-spread plate technique. The results indicated an average of 34.0% decrease in colony-forming units for A. naeslundii CH-12 and 15.7% for P. aeruginosa ATCC 27853 with the 5 Hz/15 s laser treatment, and for the 10 Hz laser frequency, a decrease of the 77.4% for A. naeslundii CH-12 and 85.8% for P. aeruginosa ATCC 27853. No bacteria were detected in the canals treated with 5.25% NaOCl. The results show an antibacterial effect of the Pumped Diodium Nd:YAG laser, depending on the radiation frequency. However, 5.25% NaOCl was more effective than either laser application.