Muscular jaw pain has different causes due to the complex nature of the chewing process. The most common are temporomandibular disorders, or TMDs, with the temporomandibular joint disorder (TMJ) being only a specific type. The jaw requires different movements for chewing controlled by an intricate balance between the bones, muscles, ligaments, and tendons. However, when this delicate balance is disrupted, it can lead to pain.
The most common cause of jaw pain is temporomandibular disorder (TMD).
Temporomandibular joint disorder (TMJ) is a specific type of TMD.
The jaw has numerous types of movements involved with chewing.
Various factors cause jaw muscles to fatigue and tighten, leading to pain.
Bones, connective tissues, muscles, tendons, and ligaments comprise the jaw.
The two main jaw bones are the mandible (diagram #1) and maxilla (diagram #2).
The mandible is the lower jaw bone and contains the lower teeth. There are left and right mandibles at birth, but they fuse within the first year. Each side has two bony areas — condylar and coronoid processes — that work together with the skull in a hinge-type mechanism to facilitate chewing. The maxilla is the upper bone of the jaw and contains the upper teeth. Unlike the mandible, which moves while chewing, the maxilla is fixed in place.
Different jaw movements
The numerous muscles, tendons, and ligaments permit different jaw movements, including:
- Opening and closing of the jaw (mouth).
- Moving the jaw forward and backward.
- Shifting the jaw from side to side.
TMD – most common cause of jaw pain:
Temporomandibular disorders (TMD) are the most common cause of jaw pain. Temporomandibular joint (TMJ) disorder is a specific type of TMD involving the temporomandibular joint. Other TMD disorders affect the jaw muscles.
The exact location of the temporomandibular joint is shown above, where the skull’s temporal bone joins the mandible’s condyle at a specific joint; thus, the term temporomandibular joint.
Symptoms of TMD and TMJ
Other symptoms of TMD/TMJ include:
- Popping or cracking.
- Limited range of motion.
- Ear pain or tinnitus (ringing in the ears).
- Vertigo (a sensation of being off balance).
What causes TMD?
With TMD, the muscles and connective tissue fatigue, tighten, and become painful.
There are many causes of TMD, including:
- Bruxism, which is grinding or clenching of the teeth, especially during sleep.
- Depression and anxiety.
- Fibromyalgia (a generalized musculoskeletal disorder).
- Disc displacement at the TMJ joint.
- Inflammatory conditions (rheumatoid arthritis or lupus).
- Various traumas of the jaw or surrounding area.
Who suffers the most from TMD?
Most people affected with TMD develop it between 20-40 years old, with women affected more often than men. Even though an estimated 65% of the population has TMD, only 10% report it to their physician and receive treatment.
Furthermore, in females younger than 30 years old, smoking is a risk factor for TMD. Most people affected with TMD develop it between 20-40 years old, with women affected more often than men.
How to diagnose muscular jaw pain
A physician can diagnose TMD by first looking at the patient's history.
With TMJ, there is pain in the TMJ area after chewing or jaw movement. There may be an audible pop, but it also exists in people without TMJ or jaw pathology (disease).
Physical examination usually presents with tenderness at the TMJ joint and other muscles involved in mastication (chewing). The doctor may press on the TMJ joint and ask the patient to open and close their mouth. They do this because some people's jaws deviate to one side when opening and closing.
Radiographs like plain X-rays can help demonstrate fundamental bony abnormalities, like fractures, cysts, or osteoporosis. A panoramic X-ray captures a special dental image of the teeth, mandible, maxilla, and TMJ joint. Even though the jaw is shaped like a horseshoe, the panoramic view is a flat two-dimensional view of the entire mouth and jaw.
After the initial X-rays, if more detailed views are needed, a doctor may order a computed tomography (CT or CAT) scan or magnetic resonance imaging (MRI) scan. These produce three-dimensional images of the jaw's structure, including bones, muscles, tendons, and ligaments. Because an MRI provides more details than a CT scan, it may be ordered for different or more difficult cases.
Laboratory tests can rule out generalized inflammatory conditions, such as an erythrocyte sedimentation rate (ESR), a rheumatoid factor, and an anti-nuclear antibody (ANA) test.
Ways to treat muscular jaw pain
Doctors will try to rule out the causes of jaw pain. If they can determine that the jaw pain is muscular, it can be treated conservatively like other muscular disorders, including medications, ice, heat, physical therapy, occupational therapy, acupuncture, or chiropractic. However, specific treatments specifically designed for jaw pain are discussed below.
- Mouthguards. They can be beneficial, especially when worn at night since many people who clench and grind their teeth often do so while sleeping. Mouthguards come in a variety of styles ranging from soft to hard. Some are molded when heated in hot water, while others are professionally crafted from a mouth mold.
- Antidepressants. Tricyclic antidepressants, commonly used to treat major depressive disorders, can be extremely helpful for easing muscular jaw pain and TMJ. Examples of tricyclic antidepressants include amitriptyline (Elavil) and nortriptyline (Pamelor).
- Eating softer rather than harder foods. Softer foods require less chewing. Therefore, avoiding foods like hard rolls or bagels, carrots, hard cereal, candies, and pretzels can help to ease symptoms. Additionally, foods like licorice, beef jerky, and tough meat require excessive chewing and can overwork and tire jaw muscles.
- Behavior changes. Teaches the person to decrease daytime clenching or grinding.
- Surgery. Should be considered but only as a last resort.
Even though jaw pain can be painful and disabling, there are numerous steps you can take to alleviate the symptoms including eating and behavior shits as well as certain medications. However, TDM tends to affect women between 20-40 years old rather than men with smoking being the main factor.