Oxidative Stress in Dental Caries and Periodontal Disease Among Secondary School Students in Duhok, Kurdistan Region, Iraq

Abstract

Background:The main oral health concerns and markers of the oral health burden globally are dental caries and periodontal diseases. In the etiology and pathogenesis of various oral disorders, including dental caries and periodontal diseases, oxidative stress has been involved. The most commonly investigated markers of oxidative stress reactions include lipid peroxidation, protein oxidation, and antioxidant status. Aim: The aim of the study was to evaluate the interrelation between markers of salivary oxidative stress on dental caries and periodontal disease among secondary school students in Duhok City. Material and methods: Across a sectional study performed on a randomized sample of 809 high school students (395 females and 414 males) aged 14-20 years from eight secondary schools from 4 quarters of Duhok city from December 2018 to May 2019. Unstimulated saliva was collected for the analysis of total antioxidant capacity (TAC) and Malondialdehyde (MDA) followed by a clinical examination. Dental caries assessment was performed using the Decayed, Missing, and Filled/Teeth (DMFT) index and periodontal status were evaluated using the Gingival Index (GI) and the Plaque Index (PI). Subsequently were divided into high caries ≥ 5 and low caries group < 5 according to caries status; furthermore, they were subdivided according to the periodontal status into students with healthy/mild gingivitis and students with moderate/severe gingivitis. Results:The study results showed that there was no significant difference between the mean TAC levels in terms of decay status and periodontal disease in females (p=0.057), males (p=0.110) and the whole sample (p=0.741). Concerning the MDA and the decayed status, the mean MDA level was higher in those with DMFT of ≥ 5 relative to those with DMFT <5 in the entire sample and male patients. While the difference between females was not significant between the two DMFT groups (p = 0.473). Significantly, higher MDA levels (p<0.01) were found in males with moderate to severe gingivitis compared with those with mild gingivitis. However, the difference among females was not significant (p = 0.890). Conclusions: MDA levels were relatively higher among students of the high caries group and periodontal disease, suggesting that oxidative stress is correlated with the process of dental caries and periodontal disease.