Salivary biomarkers for the prediction of Grade B and Grade C periodontitis: A case-control study.

Abstract

Background: The expression of the Wingless-related integration site (WNT) signaling pathway molecules has been reported to be aberrant in periodontitis.

Objectives: This case-control study aimed to determine the salivary concentrations of sclerostin (SOST), Dickkopf-related protein 1 (DKK1) and WNT family member 5a (WNT5a) and their ability to distinguish systemically healthy patients with periodontitis - across different progression rates - from periodontally healthy controls.

Material and methods: A total of 90 individuals participated in this study (30 healthy controls, 30 Grade B periodontitis patients, and 30 Grade C periodontitis patients). Salivary samples were collected using the unstimulated saliva collection method. Subsequently, clinical periodontal parameters were recorded. The enzyme-linked immunosorbent assay (ELISA) was utilized to determine the salivary levels of SOST, DKK1 and WNT5a.

Results: The salivary levels of SOST and DKK1 were significantly higher in Grade B periodontitis patients (14.85 ±3.28 ng/mL and 3.65 ±1.11 ng/mL, respectively) and Grade C periodontitis patients (7.45 ±3.84 ng/mL and 1.68 ±0.46 ng/mL, respectively) than in healthy controls (4.37 ±0.97 ng/mL and 0.88 ±0.15 ng/mL, respectively). Notably, their levels were significantly higher in periodontitis Grade B than in Grade C (p < 0.0001). The WNT5a salivary levels were also considerably higher in Grade B periodontitis patients (6.58 ±3.28 ng/mL) and Grade C periodontitis patients (13.41 ±1.73 ng/mL) than in healthy controls (2.03 ±0.31 ng/ml). Unlike SOST and DKK1, WNT5a showed significantly higher levels in periodontitis Grade C as compared to Grade B (p < 0.0001). Additionally, the receiver operating characteristic (ROC) analysis demonstrated that SOST, DKK1 and WNT5a showed significant diagnostic accuracy in distinguishing periodontitis from periodontal health with the area under the curve (AUC) values of 0.96, 0.97 and 0.99, respectively, and also in distinguishing periodontitis Grade B from periodontitis Grade C with AUC of 0.94, 0.97 and 0.92, respectively.

Conclusions: The salivary levels of SOST, DKK1 and WNT5a demonstrated high diagnostic value in distinguishing generalized periodontitis from periodontal health. The WNT5a levels increased with disease progression, effectively differentiating Grades B and C. Similarly, SOST and DKK1 also distinguished these grades, with higher levels in Grade B than in Grade C.