Extracorporeal Shock Wave Therapy Enhances IL-1b Production in Periodontal Tissues

Background: Extracorporeal shock wave therapy (ESWT) was introduced for medical therapy twenty years ago to disintegrate kidney stones, however, over the last ten years it has been used in different fields of medicine to stimulate healing processes. Though the ESWT influence on inflammatory mediators in the periodontium has not yet been studied. Objective: Investigate the changes in IL-1β concentration in the periodontium after the induction of orthodontic tooth movement with and without ESWT in a rate model. Methods: Eighteen rats were randomized into four groups: without orthodontic appliance nor ESWT (negative control:n=2); ESWT without orthodontic appliance (positive control:n=6); orthodontic appliance without ESWT (ESWT/-:n=5); and orthodontic appliance with ESWT (ESWT/+:n=5); The orthodontic appliance, incorporated a reciprocal open NiTi-coil-spring, was fabricated unilaterally to the second maxillary molar and incisor. Gingival crevicular fluid was harvested from the periodontium every day during the 4 days of study. Elisa assay was used to determine IL-1β concentrations. Results: No statistical significant difference was found in IL-1β concentrations between all groups on day 0 and between negative and positive control on day 1. IL-1β concentration rose in both ESWT/+ and ESWT/- groups on the first day, but was higher in ESWT/+ group (257.45 pg/site and 166 pg/site respectively). However, on day 2 while it kept rising in the ESWT/+ group, it decreased in the ESWT/- group (277.63 pg/site and 136.36 pg/site respectively). This increased IL-1β concentration in the ESWT/+ group was found to be statistically significant in comparison to its level on day 0 (p=0.05). On day 3, IL-1β concentrations in both groups decreased and reached a lower level in the ESWT/+ group (75.09 pg/site and 94.72 pg/site respectively). Conclusion: These results indicate that ESWT application during orthodontic tooth movement enhances IL-1β production, which may contribute to periodontal remodeling and eventually faster orthodontic tooth movement.