Short-Term Effects of Non-Surgical Periodontal Treatment on the Gingival Crevicular Fluid Cytokine Profiles in Sites With Induced Periodontal Defects: A Study on Dogs With and Without Streptozotocin-Induced Diabetes

Background: The aim of this study is to assess the short-term effects of non-surgical periodontal therapy (NSPT) on the gingival crevicular fluid (GCF) cytokine profile in sites with standardized periodontal bony defects in beagle dogs with and without diabetes. Methods: Four beagle dogs with streptozotocin (STZ)-induced diabetes and four healthy dogs were included. Fasting blood glucose levels were measured using a glucometer. In all animals, a 3-walled bony defect was created on the mesial surface of the second premolar and first molar in all quadrants. After 12 weeks, all animals underwent weekly NSPT for 3 weeks. Baseline and post-NSPT GCF samples were collected, and levels of interleukin (IL)-1, IL-1 beta, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha were measured using enzyme-linked immunosorbent assay. Statistical analyses were performed using a software program, and P values <0.05 were considered statistically significant. Results: Mean fasting blood glucose levels were significantly higher in dogs with induced diabetes than those without diabetes (P < 0.01). At baseline, mean IL-6 (P < 0.01) and IL-8 (P < 0.05) levels were higher in dogs with diabetes than those without diabetes. A significant reduction in levels of IL-1, IL-1 beta, IL-6, IL-8, and TNF-alpha was noted in dogs without diabetes 1 week after NSPT. However, this significant reduction (P < 0.05) only appeared 2 weeks after NSPT in dogs with diabetes. Conclusions: NSPT reduces GCF levels of proinflammatory cytokines in dogs with and without STZ-induced diabetes; however, chronic hyperglycemia seems to retard the effect of NSPT on GCF cytokine concentration.