Expression of toll-like receptor 4 and matrix metalloproteinase 8 in gingival crevicular fluid in patients with periodontitis

Objective: To determine the expression of TLR4 and MMP8 in gingival crevicular fluid [GCF] in patients with periodontitis. Material and Methods: Clinical samples were collected from 23 gingival crevicular fluid of periodontal disease subjects (n = 14) and healthy periodontal subjects (n=9). Measurement of Clinical parameters of probing pocket depth (PPD), bleeding on probing (BOP), and clinical attachment loss (CAL) were included as diagnostic criteria. Pocket Depth (PD) and CAL were defined as present if the PPD was ≥ 4 mm and the CAL ≥ 1 mm. Expression of TLR4 and MMP8 in the gingival crevicular fluid of deep pockets (PD≥ 6mm), shallow pockets (PD 4-5 mm) and healthy periodontal sulcus (0-3 mm) were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Statistical analysis to compare the pocket was using Independent t-test and Mann-Whitney test. Correlation between mRNA expression and clinical parameters was analyzed using Spearman’s correlation test. Results: Expression of TLR4 was higher in shallow pockets compared to the control group, but the difference was not statistically significant (p>0.05). The expression of MMP8 was higher in shallow pockets compared to the control group, but the difference was not statistically significant (p>0.05) either. There is no significant correlation between TLR4 and MMP8 with clinical periodontal parameters. Conclusion: TLR4 and MMP8 mRNA expression levels should not be used as a clinical biomarker in periodontitis diagnostic tools.