Background: Tobacco use generates reactive oxygen species that induce oxidative stress and cellular injury. Salivary biomarkers such as malondialdehyde (MDA) and lactate dehydrogenase (LDH) serve as simple, noninvasive indicators of these changes. Objective: The objective was to compare salivary MDA and LDH levels among different tobacco exposure groups. Methods: In this cross-sectional study, 140 participants (20–45 years) were allocated into five groups: active smokers, passive smokers, smokeless tobacco users, quitters, and healthy controls ( n = 28 each). Salivary MDA and LDH were estimated, and intergroup differences were analyzed using one-way analysis of variance with Bonferroni post-hoc testing ( P ≤ 0.05). Results: Active smokers and smokeless tobacco users demonstrated significantly elevated MDA and LDH levels compared to controls ( P < 0.001), with increases exceeding twofold for MDA and 100% for LDH. Passive smokers and quitters showed intermediate values, indicating partial recovery following cessation. Conclusion: Both smoked and smokeless tobacco use are associated with clinically meaningful increases in salivary oxidative stress and cellular injury markers, supporting the utility of MDA and LDH as adjunctive biomarkers in oral risk assessment.
Arunmozhi et al. (Thu,) studied this question.