Treatment with Nd:YAG Laser Irradiation Combined with or Irrigation on Periodontal Pathogens: An Study.

The purpose of this study was to evaluate the effect of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser with low concentrations of hydrogen peroxide (HO) or sodium hypochlorite (NaOCl) on viability of oral bacteria. Bacterial species , , and were grown in an anaerobic chamber at 37°C. Samples were irradiated with the Nd:YAG laser (1064 nm, 300 μm Varian tip) using parameters: 150 mJ, 20 Hz, 3 W, 50 sec, and 100 μs short pulse duration in contact mode. Treatment groups included (1) control, (2) Nd:YAG, (3) 0.5% HO, (4) Nd:YAG and 0.5% HO, (5) 0.5% NaOCl, and (6) Nd:YAG with 0.5% NaOCl. Viable colonies were counted, calculated into colony forming unit/mL, and converted into log form for statistical analysis using a two-tailed paired -test. The combined treatment with the Nd:YAG and HO showed the greatest reduction in all bacterial viability compared with other treatment groups ( < 0.001). Antiseptic solutions and laser were most effective against , least effective against but improved significantly in combination with laser irradiation ( < 0.001). Laser alone was effective against all of three bacterial species, however, it was not significant. Combination treatment with Nd:YAG laser and an oxidative disinfectant (0.5% NaOCl or HO) resulted in more effective reduction of bacterial viability than monotherapies.