[Public domain] via Wikimedia CommonsTemporomandibular joint disorder (TMJD) is characterized by severe jaw pain associated with chewing or biting down. There is no effective treatment for the disorder, which affects more than 10 million Americans. TMJD can arise from trauma, but for many cases, the underlying cause is not known, hindering attempts to develop therapeutic strategies. A study by researchers at Duke University (Durham, NC) has now identified a protein that is required for TMJD-associated pain in mice. The protein, TRPV4, may be a new target for pain relief in TMJD.