From the Guidelines
Managing trismus and improving mouth opening requires a multifaceted approach, with the most recent and highest quality evidence from 2023 suggesting the use of jaw mobilisation, jaw exercise, and jaw stretching as strong recommendations in favour of improving function and reducing pain 1. To manage trismus and improve mouth opening, the following steps can be taken:
- Start with gentle passive stretching exercises several times daily, using tools like tongue depressors stacked between the teeth or specialized devices like the TheraBite jaw motion rehabilitation system.
- Begin with 5-10 repetitions, holding each stretch for 5-7 seconds, gradually increasing duration and frequency as tolerated.
- Heat application before exercises can improve tissue elasticity.
- For medication management, NSAIDs like ibuprofen can reduce inflammation, while muscle relaxants such as cyclobenzaprine or baclofen may help with muscle spasm.
- In severe cases, botulinum toxin injections to the masseter and temporalis muscles can provide relief.
- Addressing underlying causes is crucial—treating dental infections, temporomandibular joint disorders, or oral cancers if present.
- For radiation-induced trismus, starting exercises before treatment and continuing throughout is preventative.
- Maintaining good oral hygiene and adequate hydration supports recovery.
- If trismus persists despite these measures, consultation with specialists in oral medicine, physical therapy, or pain management may be necessary for more targeted interventions, as recommended by the American Society of Clinical Oncology 1. It is also important to note that referral to rehabilitation specialists and dental professionals can help prevent trismus and treat it as soon as it is diagnosed, as suggested by the American Society of Clinical Oncology 1. Additionally, the use of custom mouth opening devices for rehabilitation of trismus and jaw motion can be beneficial, as mentioned in the Journal of the National Comprehensive Cancer Network 1.
From the Research
Management of Trismus
To manage trismus and improve mouth opening, several strategies can be employed:
- Prompt recognition of the cause of trismus and initiation of appropriate management is crucial, as delayed treatment may lead to permanent functional impairment 2
- Botulinum toxin injections into the masseter muscles have been shown to effectively reduce hypertonia and increase mouth opening in patients with spastic trismus 3
- Botulinum toxin therapy has also been found to be effective in the treatment of myofascial pain, which can contribute to trismus 4
- In cases of trismus associated with oral cancer, strategies for obviation and management include radiological and serologic prediction, surgical/reconstructive modifications, and tailored radiation therapy 5
- Rehabilitation of trismus involves accurate assessment of etiology and extent, and may include exercises, device-based interventions, and novel reconstructive methods 5
Treatment Options
Treatment options for trismus may vary depending on the underlying cause and severity of the condition:
- Botulinum toxin injections have been shown to be effective in reducing masseter muscle hypertonia and improving mouth opening 3, 4
- Conservative therapy, such as physical therapy and pain management, may also be effective in reducing pain and improving function 4
- Surgical interventions, such as reconstructive surgery, may be necessary in some cases to improve mouth opening and restore function 5
Importance of Early Intervention
Early intervention is critical in the management of trismus, as delayed treatment may lead to permanent functional impairment and decreased quality of life: