Estimation and correlation of serum and salivary C-reactive protein in oral potentially malignant disorders

Background: A large proportion of oral cancers arise from oral potentially malignant disorders (OPMDs). Very few studies have assessed serum and salivary C-reactive protein (CRP) levels in OPMDs warranting further research. Furthermore, no study has evaluated the correlation of serum and salivary CRP in OPMDs to the best of our knowledge. Objectives: The study aimed to compare serum and salivary CRP levels between subjects with OPMDs and controls along with their correlation. Materials and Methods: A total of 60 subjects with 30 subjects each in the study (Group 1) and control group (Group 2) were included. Group 1 was further categorized into group 1a, 1b, and 1c comprising 10 subjects each of Leukoplakia, Oral lichen planus (OLP), and Oral submucous fibrosis (OSMF). Group 2 comprised of 30 age and gender-matched controls. Results: Higher mean serum and salivary CRP levels were found in subjects of Group 1 (5.91 ± 3.11 mg/L and 1.00 ± 0.45 mg/L, respectively) as compared to group 2 (2.18 ± 0.66 mg/L and 0.48 ± 0.33 mg/L) with a statistically significant difference (P < 0.001). There was a positive correlation between serum and salivary CRP levels values in both group 1 (P < 0.001) and group 2. Conclusion: Higher serum and salivary CRP levels in OPMD subjects in comparison with controls indicate its role as a potential biomarker in the early detection of oral cancer. A positive correlation between the two potentiates the use of saliva as a non-invasive diagnostic tool for detection of CRP.