Abstract <p>The purpose of this study was to determine the levels of IL-17, Bcl-3 and IκBζ gene expression in the gingival crevicular fluid (GCF) of psoriatic and healthy individuals and to compare the clinical periodontal parameters in the patient and control groups. A total of 10 psoriasis patients and 2 healthy patients in the control group were included in the analysis for IL-17, Bcl-3, and IκBζ gene expression in the GCF. Periodontal health, gingival index, plaque index, and mobility (using a periotest device) levels were compared between the groups. While considering the down-expressed patients, the expression level of the Bcl-3 gene showed the most variability among the genes studied in psoriasis disease. IL-17 gene expression levels were significantly higher and up-regulated in all patients compared to the control group. In addition, when comparing IL-17 with Bcl-3, IL-17 gene expression was notably high in all patients except patients 4, 9 and 10. The highest expression levels of the IκBζ gene were observed in the patient sample, except for patients 7 and 8. While plaque index, gingival index, and pocket depth parameters were higher in the psoriasis group, there was no significant difference between the two groups (<i>p</i> = 0.257, <i>p</i> = 0.390, <i>p</i> = 0.240, respectively). In the periotest (mobility) parameter, while the mean value was higher in the psoriasis group significantly (<i>p</i> = 0.030), clinically mean values of two groups were in the same grade according to Miller mobility index. The IκBζ gene showed notable high expression levels in psoriasis patients. It was concluded that psoriasis may be associated with periodontitis.</p> Clinical Trial Registration Number <p>NCT06408454–05/06/2024.</p> Name of the Trial Register <p>Interleukin- 17 (IL-17), Bcl-3, and NF-kappa-B Inhibitor Zeta (IκBζ) Expression Levels in the Psoriasis Patients.</p>