Purpose: To evaluate the efficacy of Nd:YAG laser in destruction of Porphyromonas gingivalis and Prevotella intermedia and to assess surface damage after ablation with laser in an in vitro tissue model. Materials and Methods: Subgingival plaque samples were collected from patients with generalized chronic periodontitis with a sterile curette. P. gingivalis and P. intermedia were isolated and cultured on blood agar plate which was the test group, while blood agar plate without colonies was the control group. Nd:YAG laser was applied to both plates and the results were observed under a surgical microscope at 24X magnification. Results: Distinct craters with flat bottoms were seen in the test group after application of Nd:YAG laser, due to lysis of the colony forming units. No change was noted on the surface of the control group after irradiation with Nd:YAG laser. Conclusion: Nd:YAG laser can selectively destroy pigmented periopathogenic bacteria, while leaving the surrounding tissue intact.
Keywords: Nd:YAG laser, Porphyromonas gingivalis, ablation, blood agar