Background:Periodontitis destroys the tooth's supporting structures and attachment apparatus. Local or systemic factors can cause it. Traditionally, diagnosis is based on clinical parameters that may not consistently reflect an accurate confirmation. Biochemical and genetic analyses can provide deeper insights. MicroRNAs (miRNAs) regulate the immune and inflam-matory response to microbial pathogens. Detecting and evaluating miRNAs can be an important diagnostic parameter. This study aimed to assess the expression of miRNA 146a,200c, and its target gene PTEN to non-surgical periodontal therapy in serum and saliva.Materials and Methods:This interventional comparative study was conducted on 120 patients of both genders, ages between 35 and 55. Non-surgical periodontal therapy (NSPT) scaling and root planing were performed on all subjects, and their saliva and serum samples were collected before and after 8 weeks of NSPT. Quantitative rt-PCR (reverse transcriptase Polymerase Chain Reaction) analysis was conducted on all samples. The statistical analysis was done using SPSS version 22, and comparisons were made using paired t-tests, independent t-tests, and Pearson’s correlation coefficient. The statistical significance level was set at a ‘P’ value of less than 0.05.Results:It has been observed that there was a significant difference of miRNA in both serum and saliva samples 146a,200c, and the PTEN gene expression, from the beginning to 8 weeks. Sig-nificant variation was not observed when comparing the levels between serum and saliva.Conclusion:miRNA 146A, 200c, and PTEN genes are interrelated with periodontitis. We can consider them as future biomarkers of periodontal diseases.