Periodontitis was induced by a single intragingival injection of 1 μl LPS (10 μg/μl), Our results show that 14 h after intragingival injection of LPS, there was a high tissue damage associated with bone resorption, and in gingivomucosal tissues there was a significant expression of NF-kb p65 and pro-inflammatory cytokine as well as a higher expression of COX-2 and iNOS, activation of the apoptotic process, and also increased levels of NGF expression, often associated with a higher nociceptive perception.
The validation of the association of rs20417 by the htSNP rs6681231 provides evidence for a general genetic risk of COX-2 variants in the pathogenesis of periodontitis.