Assessment and Comparison of 8-Hydroxy-2-Deoxyguanosine (8-OHdG) Levels in Saliva and Serum among Healthy Subjects, Periodontitis, and Oral Submucous Fibrosis (OSMF) Patients

Abstract

Introduction: Oxidative stress plays a critical role in the pathogenesis of oral diseases such as periodontitis and oral submucous fibrosis (OSMF). 8-Hydroxy-2-deoxyguanosine (8-OHdG) is a marker of oxidative DNA damage. This study aims to compare 8-OHdG levels in saliva and serum among healthy individuals, periodontitis patients, and OSMF patients to elucidate the extent of oxidative damage in these conditions.

Materials and Methods: This cross-sectional study included 90 participants divided equally into three groups: healthy subjects, periodontitis patients, and OSMF patients. Saliva and blood samples were collected from all participants in the morning. 8-OHdG levels were quantified using enzyme-linked immunosorbent assay (ELISA). Statistical analyses, including ANOVA and correlation tests, were performed to compare 8-OHdG levels and assess the relationship between salivary and serum 8-OHdG.

Results: The mean salivary 8-OHdG levels were significantly higher in OSMF patients (8.9 ± 2.3 ng/mL) and periodontitis patients (6.2 ± 1.8 ng/mL) compared to healthy subjects (3.4 ± 1.1 ng/mL). Similarly, mean serum 8-OHdG levels were highest in OSMF patients (10.2 ± 2.8 ng/mL), followed by periodontitis patients (7.5 ± 2.0 ng/mL), and lowest in healthy subjects (4.1 ± 1.3 ng/mL). A significant positive correlation was observed between salivary and serum 8-OHdG levels in all groups, with correlation coefficients of 0.72, 0.78, and 0.81 for healthy subjects, periodontitis patients, and OSMF patients, respectively.

Conclusion: The study demonstrates elevated oxidative stress in periodontitis and OSMF patients, with the highest oxidative burden in OSMF patients. The strong correlation between salivary and serum 8-OHdG levels suggests that salivary 8-OHdG can serve as a reliable non-invasive biomarker for systemic oxidative stress. These findings highlight the potential of 8-OHdG measurement for early detection, monitoring, and management of oxidative stress-related oral diseases.