Abstract
The main cause for the development of periodontitis is the accumulation of subgingival microbial deposits organized tightly to the porous surface of the tooth cementuni. The growth of the microbial populations and the immunological reaction of the host organism are responsible for the destruction of periodontal ligament apparatus. The primary goal in the treatment of periodontitis is the complete removal of subgingival bacterial deposits. The large amount of evidence establishing a microbial etiology for periodontitis (has been the basis for the development of antimicrobial treatment approaches. Photodynamic therapy (PDT) employs a non-toxic dye, termed a photosensitizer (PS), and low intensity visible light which, in the presence of oxygen, combine to produce cytotoxic species. In this in vitro protocol study it was tested the bactericidal efficacy of Diode laser (Oralia), of Hydrogen Peroxyde and the association Diode Laser-Peroxyd Hydrogen (PDT) on Prevotella intermedia, Peptostreptococcus micros and Fusobacterium nucleatum, three of the most aggressive bacteria envolved on periodontal disease.