Interleukin 17 (IL-17) and interleukin 23 (IL-23) levels are modulated by compressive orthodontic forces in humans

Objective: The purpose of the investigation was to evaluate whether the application of compression forces exerted on the periodontal ligament during orthodontic movement is reflected at the level of interleukin (IL)-17 and IL-23. Materials and methods: The gingival crevicular fluid (GCF) samples from the compression sites of 32 molars from 16 patients prescribed with modified Hyrax appliance were collected. The GCF were analyzed for IL-17, IL-23, and IL-1 beta (Control) at baseline and at 1, 7, and 14 days of active wear of the appliance. Results: Orthodontic forces resulted in increased levels of IL-17 and IL-23 in the GCF, which were statistically significant at 7 days of force application at compression sites. At day 14, levels decreased to baseline; IL-1 beta levels (positive control) were more elevated at all times after force application. IL-17 and IL-23 levels were significantly lower than IL-1D, and undetectable in some samples. Conclusion: Upregulation of IL-17 and IL-23 occurred in response to the force application in compression sites. Monitoring the levels of inflammatory mediators might be a clinically useful procedure, as they may help to define optimal forces to produce the most rapid tooth movement. (C) 2019 World Federation of Orthodontists.