While the term “lockjaw” is often associated with tetanus, it medically refers to a broader condition that restricts your ability to open your mouth. This article explores the connection between wisdom teeth and this restricted jaw movement, explaining how issues with these molars can lead to such a problem.
What Trismus Is
Trismus, commonly known as lockjaw, is a condition characterized by the painful restriction of mouth opening, resulting from spasms or inflammation of the masticatory muscles used for chewing. Normal mouth opening typically ranges from 35 to 45 millimeters, or approximately the width of two to three fingers. Individuals experiencing trismus find their ability to open their mouth significantly reduced, making everyday activities like eating, speaking, or maintaining oral hygiene challenging. This condition can manifest as tightness, stiffness, or cramping in the jaw muscles, sometimes accompanied by pain even at rest. While the term “lockjaw” was historically used to describe tetanus, trismus itself is a symptom that can arise from various underlying causes.
Wisdom Teeth as a Cause
Wisdom teeth, or third molars, can lead to trismus primarily due to complications. One common issue is impaction, where a wisdom tooth is unable to fully erupt through the gums and jawbone. An impacted tooth can exert pressure on surrounding tissues and structures, leading to inflammation and restricted jaw movement. Infections, particularly pericoronitis, are a frequent cause of trismus associated with wisdom teeth. Pericoronitis is an inflammation of the gum tissue around a partially erupted wisdom tooth, often occurring when bacteria and food particles become trapped under a flap of gum. This infection can cause significant swelling and muscle spasms in the jaw, leading to limited mouth opening. Trismus is also a common temporary side effect following wisdom tooth extraction surgery. This post-operative stiffness can result from the inflammation caused by the surgical procedure, hyperextension of the jaw during the extraction, or even needle injury to a muscle during local anesthesia.
Recognizing and Responding to Trismus
The most noticeable indicator of trismus is a reduced ability to open the mouth fully, which can be measured by how many fingers can be inserted between the upper and lower front teeth; usually, less than three fingers indicates trismus. Beyond limited jaw movement, individuals might experience pain in the jaw, difficulty chewing, swallowing, or speaking. If an infection is present, additional signs such as facial swelling, fever, or swollen lymph nodes in the neck may accompany the jaw stiffness. If you experience persistent jaw pain, difficulty eating, or increasing swelling, it is important to seek professional dental or medical attention. Timely intervention can prevent the condition from worsening and address any underlying infection or inflammation.
Managing and Avoiding Trismus
Managing trismus involves addressing the underlying cause and alleviating symptoms. For infections, antibiotics are typically prescribed, and pain management often includes over-the-counter or prescription anti-inflammatory medications and muscle relaxants. Applying warm compresses to the jaw area for 15 to 20 minutes several times a day can help relax the muscles and promote blood flow. Gentle jaw exercises, such as slowly opening the mouth as wide as comfortable and moving the jaw side to side, are important to gradually restore range of motion; a physical therapist or dentist may provide specific exercises or recommend jaw-stretching devices. In cases where a problematic wisdom tooth is the root cause, its removal might be necessary to resolve the trismus.
To avoid trismus, maintaining good oral hygiene around erupting wisdom teeth can help prevent infections like pericoronitis. Regular dental check-ups allow for early assessment of wisdom teeth, and timely removal of those prone to complications can prevent future occurrences of trismus.