Can delta neutrophil index values predict the success of periodontal treatment in patients with periodontitis?

Objectives The aim of this study was to evaluate the effect of delta neutrophil index (DNI) on non-surgical periodontal therapy (NSPT), whose role has been documented in the pathogenesis and follow-up of periodontal disease. Methods and materials The study included 35 patients with stage 3, grade A periodontitis (test group) and 35 patients without periodontal disease (control group). Initially, periodontal parameters were recorded and blood samples were taken from all patients. For patients with periodontitis, periodontal parameter measurements and blood sample analyses were repeated 3 months after NSPT. Results After NSPT, DNI, CRP (C-reactive protein), neutrophil count, WBC (white blood cell), and neutrophil–lymphocyte ratio (NLR) values decreased in the test group, but did not reach a statistically significant level ( p > 0.05). When the inflammatory variables were examined, significantly higher CRP, IG (immature granulocytes), DNI, neutrophil count, and WBC were observed in the test group compared to the control group ( p < 0.05). In the test group, periodontal parameters were lower 3 months after NSPT than at baseline ( p < 0.05). Conclusion Consistent with previous findings in the literature, the patients with periodontitis were determined to have higher levels of DNI, CRP, neutrophils, and WBC, compared to the individuals without periodontitis. Although a decrease was seen in DNI after NSPT, this was not at a significant level. Clinical relevance DNI is a guide in the evaluation of inflammation at the onset of periodontal disease, but studies with a larger number of cases are needed to use these parameters in the evaluation of treatment success. Trial registration This study was retrospectively registered on December 27, 2022, with the number NCT05666622 at http://www.clinicaltrials.gov .