TRPA1 and Arthritis: In the present study, we used two distinct unilateral models of TMJ inflammatory hyperalgesia, relevant to arthritis and obtained similar results to show: (i) ipsilateral pain-related behaviours (hyper-nociception) as measured by monitoring front paw wiping, (ii) increased markers of TMJ inflammation as measured by a non-invasive technique to measure cheek skin blood flow as well as pro-IL1β/mature IL-1β expression, and (iii) for the first time, we show a dependence of the hyper-nociception and inflammatory phases on TRPA1 and NLRP3 in mouse TMD models.