NSPT is the gold‐standard treatment for periodontal pockets < 6 mm in depth, however, successful outcomes are not always guaranteed due to several factors. Periodontitis‐associated tissue destruction is evidenced by the increased level of soluble E‐cadherin and reduced antioxidants in oral fluids which could be used as predictors for success/failure of NSPT.

Patients with periodontitis (n = 24) were included in this clinical trial and full‐mouth periodontal charting was recorded for each patient. GCF samples from periodontal pockets with probing pocket depth (PPD) 4–6 mm from the interproximal surfaces of anterior and premolar teeth were obtained. These sites subsequently received NSPT and were clinically re‐evaluated after 1 and 3 months. Levels of GCF E‐cadherin and TAC levels were assayed using ELISA.

All clinical periodontal parameters were significantly improved 3 months after completion of NSPT. These outcomes were associated with a significant decrease in E‐cadherin levels and GCF volume, while TAC levels were significantly increased in samples obtained in follow‐up appointments. Binary regression model analysis showed that PPD, GCF volume, E‐cadherin, and TAC levels could significantly (p < .05) predict the outcomes of NSPT. The cut‐off points for PPD, GCF volume, E‐cadherin and TAC were 5 mm, 4 × 10⁻³, 1267.97 pg/mL and 0.09 μmol/g, respectively.

NSPT improved clinical parameters along with increased antioxidants capacity and epithelial pocket lining integrity. Discrimination of favorable/unfavorable responsiveness of periodontally diseased sites to NSPT could be possible by using GCF volume, PPD, E‐cadherin and TAC level assessments.