What is trismus?

 I have trismus now what?

Trismus is the inflammation of muscles of mastication causing restricted mouth movement. There is pain in the muscles and joints, which results in pain with any movement.  It is a frequent result to surgical removal of mandibular third molars (lower wisdom teeth). Trismus usually resolves on its own in 10–14 days, during which time eating and oral hygiene may be more difficult.  It does occur do to injection of local anesthetics and is more likely from the physical trauma of the injection itself on the medial pterygoid muscle.  By rarely I mean I see it at my office between 0-2 times a year, less than 1 average.

 Muscle trismus Treatment

To prevent trismus progression to a chronic state, treat early with heat, analgesics, muscle relaxants, and exercises. The application of heat (e.g. heat bag extraorally, and warm salt water intraorally) will help reduce the severity and duration of the condition.  Additionally, control of symptoms with pain medications (NSAIDs) and muscle relaxants may be used.  Passive range of motion stretching needs to be done 10 times per day.  Passive range of motion refers to the moving of body parts without activating muscles to perform the movement.  In this case that means you use your hands to pull your lower jaw open as far as you can and holding it for 30 seconds.
trismus treatment
Some very fake acting of trismus suffering.

Bottom line for trismus treatment

1.  Take 800mg ibuprofen three times a day until symptoms are gone, up to 10 days.
2.  Use heat 15-20 minutes at a time 4-10 times a day
3.  Take Flexeril (cyclobenzaprine) 10mg at night.  Can take 10mg in morning too but has side effects!
4.  Physical Therapy: open and close as well as side to side movements 5 minutes every 3 to 4 hours. Chewing gum for 5 minutes every 4 hours will take care of this.  Also use passive range stretch and hold as wide as can for 30 seconds 10 times a day.
5.  If the pain is persistent and continues for more than 10 days I want a phone call.  That could be a sign of an infection setting in.
flexeril main side effects are drowsiness, dizziness and lightheadedness do not take with alcohol or if have taken MAO inhibitors within 14 days

Another similar condition is jaw joint and muscle strain/sprain (JAMSS)

JAMSS describes acute trauma to the joint or muscles from dental work. It is a common occurrence.

What is JAMSS feel like?

Symptoms vary and last for just a few days to several weeks in the acute phase. Patients will experience any or all of the following.

  • Pain in front of the ear (joint pain)
  • Inability to open all the way
  • Pain to chewing or speaking

What are the higher risk procedures? What procedures should you consider pre-dosing ibuprofen for?

  • The further back the more risk.
  • The longer the procedure will take the more risk.
  • The more pressure that the dentist uses the more risk, which likely means an extraction.
  • A female patient is also higher risk, although that may relate to mouth size.

We have a few risk factors that we use to decide whether or not to give anti-inflammatory medication before we start. These are guides more than rules for us and we just give 400 mg ibuprofen but if they can not take that then we do 500 mg Tylenol.

  1. Does the patient already suffers from chronic pain or TMD then they get ibuprofen at the start of their visit.
  2. If we are working on a molar for over an hour or more on a female.
  3. If we are taking out a tooth.
  4. If we are doing a root canal.

Long term issues with these acute injuries

These acute injuries can trigger chronic TMD in susceptible patients. More than 50% of patients state their TMD report their initial onset of pain was from dental care.

Treatment for JAMSS is similar to Trimus as both are about getting inflammation under control quickly.

We use similar recommendations as Brady April 2017 Inside Dentistry

  1. Limit clenching, grinding, and other forms of overuse of the jaws.
  2. Stretchering
  3. Tylenol and Advil alternating
  4. Hydrotherapy or alternating hot and cold packs.