In the present study, we have explored the immune activation and the expression of the intracellular TLRs - TLR3, TLR7, TLR8, and TLR9 in OL without and with dysplasia, and in oral squamous cell carcinoma (OSCC).<h4>Patients and methods</h4>Immunohistochemistry was performed on 19 OL patients without dysplasia (OL-no) and 13 patients with dysplasia (OL-dys) and 10 OSCC patients. This evidence concerns the gene TLR9 and dysplasia.