Comparison and correlation of Lactate dehydrogenase levels of saliva and serum in healthy subjects, patients with gingivitis and chronic periodontitis

Background: Periodontal disease is a chronic tissue-destructive inflammation, which destroys tooth-supporting structures and ultimately leads to tooth loss. Early diagnosis and treatment of periodontal diseases can reduce the risk of tooth loss in general population. Several biomarkers like Lactate dehydrogenase (LDH) have been proposed for early detection of periodontal disease from saliva, serum and gingival cervicular fluid. Aims: To assess and correlate the LDH levels in saliva and serum of healthy subjects, subjects with chronic gingivitis and periodontitis and to compare the saliva and serum LDH levels in all three groups. Materials and methods: Total 33 subjects aged 20– 45 years were considered for the study. The subjects were divided into three groups based on periodontal parameters as healthy subjects, chronic generalized gingivitis and chronic generalized periodontitis. Two ml of un-stimulated whole saliva and two ml of blood was collected from all the subjects and the level of LDH in both saliva and serum were measured and compared using commercially available kit. Statistical analysis: Statistical analysis was carried out using student t test and ANOVA with the help of SPSS software and P value <0.05 was considered as significant. Results: The clinical parameters like gingival index, plaque index, probing pocket depth and clinical attachment level were statistically significant between healthy subjects, patients with generalized gingivitis, and those with chronic periodontitis. Serum and Salivary LDH levels were found to be within normal limits in healthy subjects where as it was significantly increased in patients with gingivitis and chronic periodontitis. The activity of LDH increased linearly as the disease progressed. Conclusion: LDH levels in saliva as well as serum increased with periodontal disease progression. There was no significant difference observed between saliva and serum LDH levels. Estimation of salivary LDH can be used as risk predictor in patients with periodontal disease.