This book highlights the Photodynamic Therapy using Indocyanine green dye as photosensitizing agent, conducted on patients suffering from chronic periodontitis. We evaluated the efficacy of this therapy on various clinical and biochemical parameters. Clinical parameters included were as - Gingival Index, Plaque Index, Clinical Attachment Level, Periodontal Pocket Depth and biochemical parameters as - Reduced Glutathione (GSH) Level, Oxidized Glutathione (GSSG) Level and Glutathione Redox balance (GSH:GSSG). All the parameters were compared and evaluated on different time intervals. And the final results achieved were impressive. With colored photographs, bar graphs and tables.