Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 12 1 2013 03 15 75 80 EN Ehsan Darabi Department of Peridontotics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Zeinab Kadkhoda Department of Peridontotics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Aliakbar Amirzargar Molecular Immunology Research Center, Tehran University of Medical Sciences, Tehran, Iran 2015 10 16 Peri-implantitis is a multi-factorial disease involving peri-implant tissues and resulting in therapeutic failure. Inflammatory mediators and cytokines in the Gingival Crevicular Fluid (GCF)  have  pivotal  roles  in  the  disease pathogenesis  and  could  be  used  for  disease monitoring. Therefore, the  present  study was conducted  to  compare the GCF  levels of TNF-α and IL-17 between patients with peri-implantitis and healthy implants. In this case-control study, 24 patients with peri-implantitis and 18 individuals with healthy implants referring to  faculty of dentistry in Tehran  University of Medical Sciences were selected. GCF was collected by paper cons number 30. Samples were preserved in PBS -70ºC. TNF-α  and IL-17 levels in GCF  were determined by ELISA method.  Data  were analyzed by SPSS software version 13, using descriptive indices and independent t tests. Mean probing depth in peri-implantitis and control groups were 6.2 ± 1.1 and 3.7 ± 1.6 mm respectively. Mean level of IL-17 in patients with peri-implantitis was significantly more than the control group (19.8 ± 16.0 versus 9.3 ± 8.4 pg per site in 40 seconds, p=0.016). Also, mean level of TNF-α in patients with peri-implantitis was more than control group (39.0 ± 3.9 versus 14.5 ± 9.0 pg per site in 40 seconds, p =0.000). The  significant higher  levels of  TNF-α  and  IL-17  in  patients  with  peri-implantitis compared to control group indicated the pivotal role of these cytokines in peri-implantitis and could be suggested as diagnostic markers and in future possibly for immunomodulatory treatments. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/531 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/531/473