Expression of IL-6, IL-10, IL-17 and IL-33 in the peri-implant crevicular fluid of patients with peri-implant mucositis and peri-implantitis

Objectives: The aim of this study was to compare the levels of IL-6, IL-10, IL-17 and IL-33 in the peri-implantar crevicular fluid (PICF) and in parotid gland saliva (PGS) of healthy patients, and peri-implantitis and peri-implant mucositis patients.

Materials and methods: The PICF was collected from 40 implants as follows: 10 peri-implant mucositis patients, 20 peri-implantitis patients and 10 healthy patients. The PICF and PGS samples collected from each patient were quantified for IL-6, IL-10, IL-17 and IL-33 by enzymatic immunosorbent assay (ELISA).

Results: IL-6, IL-17 and IL-33 levels on PIFC were significantly higher in peri-implantitis group when compared to healthy group. IL-17 and IL-33 levels in PIFC were significantly higher in peri-implant mucositis group than in healthy group. There was no significant difference when comparing IL-6, IL-10, IL-17 and IL-33 levels in PGS among healthy, peri-implant mucositis and peri-implantitis groups.

Conclusions: Therefore, as in patients with peri-implantitis there were significantly higher levels of IL-6, IL-17 and IL-33 in PICF, we believe that these cytokines were intensifying local inflammatory process, and contributing to clinical aspects such as increased marginal bleeding and probing depth found in patients with peri-implantitis. Furthermore, as IL-17 and IL-33 were increased in patients with peri-implant mucositis, hypothesized that these cytokines were also contributing to the inflammatory process observed in this disease.