Temporomandibular disorders (TMDs) refer to issues with the jaw, specifically with jaw joints or the muscles surrounding them. These issues bring about symptoms for patients that can be extremely distressing and chronic if not properly addressed. These symptoms can involve severe pain and discomfort of the head or facial area, including tooth or neck pain, dizziness or hearing loss. TMDs affect around 20 to 30 per cent of the adult population, yet reasons as to why these disorders occur are not always clear and as a result, therapy options are not consistently effective. Because of the lack of clarity in this field, Dr Naoto Hirose, from the Department of Orthodontics and Craniofacial Developmental Biology at Hiroshima University Graduate School of Biomedical and Health Sciences and his team are working to elucidate factors contributing to the development of TMDs, as well as potential treatment options. So far, their work has focused on the relationship between mechanical stress and osteoarthritis, which is a cartilage degenerative disease. They have proven that excessive mechanical stress, specifically in the craniofacial area, leads to damaged cartilage, which in turn leads to TMDs, such as those relating to osteoarthritis. However, they have also discovered a promising remedy to the problem. Some of their most recent research focuses on the protein semaphorin3A (Sema3A) and its potential as an anti-inflammatory agent.