IL1B and synovitis: However, activated synoviocytes in inflammatory synovitis produce and release a large number of pro-inflammatory factors when synovitis occurs, such as IL-1β, IL-6, MMPs and TNF-α, which mediate cartilage destruction and TMJ inflammation through various ways (Yuan et al., 2004; Sellam and Berenbaum, 2010; Jiang et al., 2016; Ulmner et al., 2022).