Article type :
Review Article
Author :
Trupti Sarda, Surekha Rathod
Volume :
4
Issue :
1
Abstract :
As soon as oxygen was used as the terminal electron acceptor in aerobic respiration, then came the curse in the form of reactive oxygen species (ROS). So as to overcome this problem the evolving organism had developed elaborate defence machinery to escape from these reactive by-products of its own metabolism, and also developed a mechanism by which there is utilization of these species in physiological processes to gain a survival advantage. Thus it can be said that reactive oxygen species (ROS) exert a multitude of biological effects that ranges from physiological regulatory functions to damaging alterations participating in the pathogenesis of number of diseases.
Periodontitis, an inflammatory disease of the supporting tissues of the teeth, is initiated and perpetuated by a small group of predominantly gram-negative, anaerobic or microaerophilic bacteria that colonize the subgingival area. These bacterial species result in the production of various cytokines including interleukin?8 and TNF??, further causing an increase in number and activity of polymorphonucleocytes (PMN) along with these cytokines, PMNs also produce reactive oxygen species (ROS) superoxide via the respiratory burst mechanism as the part of the defence response to infection. ROS, when produced in excess, have deleterious effects on tissue cells. Human body has its own defence mechanisms to eliminate them as soon as they are formed so as to counter the harmful effects.
Recently, as the medical and dental research regarding ROS, free radicals antioxidant defence mechanisms has expanded tremendously, this review paper focuses on the key roles of ROS in both health and periodontal disease.