Trismus treatment

Karen Harnett explains how to improve your patients’ quality of life.

Temporomandibular disorders (TMD) is a collective term for conditions which affect the temporomandibular joint (TMJ) or jaw joint and the surrounding muscles. TMD is common, affecting eight to 15 per cent of the adult population in the UK. It is caused by problems which affect the masticatory system. Trismus is one of these conditions – in which a patient is only able to open their mouth 35mm or less.

Trismus and its causes

Trismus has many causes, including trauma, surgery (including wisdom tooth removal), radiation treatment, TMJ problems, arthritis, infection, and minor trauma (which may include bruxism). Because trismus can happen as a result of a number of things, it is important to be vigilant in order to prevent as much pain for your patients as possible.

Trismus tends to develop slowly, and in some cases, patients don’t notice that they’re struggling until they cannot open their mouth more than 20mm. It is important to catch this problem early and begin treatment as soon as possible, as it will likely be more effective early on and cause patients less pain. This is why being proactive in looking for signs of trismus is important. The ‘three finger test’ is a simple check in which a patient inserts three fingers between their central incisors. If fewer than three fingers fit in this space, the mouth opening is not considered functional as there is too much restriction – trismus is likely.