RESUMEN
Background:Oral premalignancies are a group of disease or syndromes which if left untreatedcanleadtocancer.ItcarriesagreatsignificanceinIndianperspective. Theactual figure of oral cancers arising from oral premalignancies is not known and to predict accuratelythemalignanttransformationsofthemisstillnotpossible.Oxidativestressisa known player behind cancerogenesis. Recently decreased Paraoxonase-1 activity and increasedoxidativestressmarkerswarefoundtobeassociatedwithOralSquamousCell Carcinoma. So, thereis astrongpossibilityofasimilar findingin Oral Premalignanciestoo. Aim: This studyaims to investigatethecor-relation between serum PON-1 activityand oxidative stress markers (MDA& Vitamin C) in patients with Oral Premalignancies. MaterialandMethods:Atotalof62patientswithclinically diagnosedoralpremalignant lesions anddiseasedcontrolswerechosenforthe study. Venous bloodsampleswerecollectedandPON-1,MDA (inse-rum)&Vitaminc (inplasma) wereanalysed spectro-photometrically. Results:A significant decreased serum PON-1 activity (P<0.05) and concomitant significantlyincreased serum MDA(P<0.05)anddecreased Vitamin Clevels (P<0.05) were observedinpremalignanciescomparedtothecontrols.Thesefinding weremorepronounced inOral Leukoplakia (OL) thaninOral Submucous Fibrosis (OSMF)withasignificantdifference.Meanlevelsoftheanalysedparameters differedaccordinglyin theclinicalgrades of oral premalignancies. Conclusion:Itcanbeenvis-agedthatserumPON-1activity andincreasedoxidativestress mightbe acontributingfactorbehindpathogenesisandprogressionofOralPremalignant Diseases