New Biomarker Evidence of Oxidative DNA Damage in Whole Saliva From Clinically Healthy and Periodontally Diseased Individuals

Abstract
There is an increasing body of evidence implicating reactive oxygen species in the pathogenesis of periodontal tissue destruction. 8-Hydroxy-deoxyguanosine (8-OHdG) is one of the most commonly used markers to evaluate oxidative damage in a number of disorders including chronic inflammatory diseases. The aim of the present study was to evaluate 8-OHdG levels in whole saliva of patients with periodontitis and to assess the changes after initial treatment.Saliva samples were collected from 78 patients with untreated periodontitis and 17 healthy control subjects. Clinical parameters and levels of 8-OHdG were assessed first to establish a baseline and again after initial periodontal treatment from 15 patients. 8-OHdG levels were determined by enzyme-linked immunosorbent assay.The mean value of 8-OHdG in the saliva of periodontally diseased subjects, 4.28 +/- 0.10 ng/ml, was significantly higher (P<0.01) than that of clinically healthy subjects (1.56 +/- 0.10 ng/ml). A significant decrease in salivary 8-OHdG was observed after therapy (P<0.01).In the present study, we evaluated for the first time 8-OHdG levels in whole saliva of patients with periodontitis and assessed changes after initial periodontal treatment. Our study indicated that 8-OHdG levels in saliva appear to reflect the status of periodontal health.