What Causes Dental Trismus?

What is dental trismus?

Dental trismus is also known as ‘lockjaw’, a condition in which one is unable to open the mouth properly. There are several ways to identify dental trismus, the most common being the inability to open the mouth beyond two fingers width.

What’s the impact of dental trismus?

There are several impacts of limited jaw opening and/or jaw movement, a major one being pain. Additionally, trismus can cause difficulty during eating, talking and cleaning teeth. In the long run these restrictions can lead to nutritional deficiency and the development of dental disease.  

What are the main causes?

The three main causes of dental trismus are:

Temporomandibular joint disorder (TMJ)

There are two temporomandibular joints: one on each side of the jaw, connecting the jawbone to the skull. These joints act as a sliding hinge, allowing for the movements required to chew. When there is a dysfunction in these joints, it can lead to general mouth pain, difficulty or pain when chewing, and dental trismus.

What causes dental trismus?

This joint dysfunction can have several causes, including genetics, trauma, surgery, arthritis and stress. In regard to stress, it’s not the stress itself that is the cause, but the associated behaviours such as teeth grinding and jaw clenching.  

In most cases, management by physical therapy and medication is successful. In more extreme cases, a surgical procedure might be needed.

Muscle conditions

Healthy muscles are key for movements in the entire body, and when it comes to the mouth it is no different. If the muscles required for chewing become inflamed or injured (due to surgery, dental treatment or anesthesia), it can limit the ability to open the mouth.

Infection

Infections can cause swelling and in the case of an infection near the jaw, can limit the ability to open the mouth causing trismus. It is extremely important to treat this type of infection immediately, not just because of the trismus, but because there is a risk of the infection spreading to other parts of body, causing major complications.

In cases like this, treating the infection will reduce the swelling and heal the dental trismus.

If you are experiencing trismus book a consultation with Dr Kate Amos or Dr Sam Rosehill at Ethical Dental on 6652 3185 or book online.