Increased expression of IL-17 in oral mucosal tissues bordering the non-healing extraction socket of BRONJ patients. A and B, Immunofluorescence studies showed increased expression of IL-17 in both CD4+ T cells and CD68+ macrophages in mucosal tissues bordering the extraction sockets of patients manifested BRONJ lesions (BRONJ) or patients with history of zoledronate treatment without clinical BRONJ (Non-BRONJ) (n=5), whereby oral mucosal tissues from healthy patients who underwent routine dental extraction for other non-inflammatory mucosa conditions (Normal) or healthy patients with diagnosis of inflammatory gum disease, specifically, active periodontitis with resultant tooth loss (Periodontitis) were used as controls (n=5). Scale bars, 50μm. C, IL-17 levels in the tissue lysates were examined by ELISA. Data are mean ± SEM of multiple fields in n=5 per group. *P < 0.05; **P<0.01.