"TMJ" is actually an abbreviation for the Temporomandibular Joint. You have two of these joints, one on each side of your head, located just in front of your ears. They act like a sliding hinge, connecting your lower jawbone (mandible) to your skull's temporal bone. These complex joints, along with a network of muscles and ligaments, enable essential movements like chewing, talking, yawning, and swallowing.

See the picture below for the TM joint on either side of your face.

Royalty free generic image of a human skull with arrows pointing to the TM joint.

When people refer to "TMJ," they are often actually talking about Temporomandibular Disorders (TMDs). TMDs are a group of more than 30 conditions that cause pain and dysfunction in these jaw joints and the muscles that control jaw movement. It's a broad term because the issues can arise from problems with the joint itself, the surrounding muscles, or a combination of both.

Key points about TMDs:

They are relatively common, affecting between 5% and 12% of the general adult population.
They are twice as common in women than in men, particularly in women between 35 and 44 years old.
Many TMDs are temporary and may resolve on their own, but for some, they can become chronic and debilitating.
The exact cause is often multifactorial and not always clear, but contributing factors can include genetics, psychological stress, injury, teeth grinding or clenching (bruxism), and other co-occurring conditions like headaches or fibromyalgia.

What are Common Symptoms of TMD?

TMD symptoms can vary widely in intensity and presentation, but here are the most common ones:

Jaw Pain or Tenderness: This is the most frequent symptom. It can be localized to the jaw joint area, the chewing muscles, or spread across the face. Pain often worsens with jaw movement (chewing, talking, yawning).
Headaches: Often described as tension headaches or even migraine-like, sometimes felt behind the eyes or in the temples.
Earaches: Pain in or around the ear that isn't caused by an ear infection. Some individuals also report ringing in the ears (tinnitus) or even dizziness.
Difficulty Chewing or Pain While Chewing: The jaw may feel tired, sore, or simply unable to chew effectively.
Clicking, Popping, or Grating Sounds in the Jaw Joint: These sounds may occur when opening or closing the mouth, or when chewing. While clicking or popping without pain is common and usually not a sign of a TMD that needs treatment, painful sounds are a key indicator.
Limited Jaw Movement or "Locking" of the Jaw: The jaw might get temporarily stuck in an open or closed position, making it difficult to fully open or close the mouth.
Neck Pain: Due to the interconnectedness of jaw muscles with neck and shoulder muscles, tension can refer pain or contribute to discomfort in the cervical spine.
Facial Pain: A general aching or discomfort throughout the face, often radiating from the jaw area.
A Change in the Way the Upper and Lower Teeth Fit Together: Your bite might feel "off."
Swelling: Sometimes swelling can be noticed on the side of the face.

What is TMJ and TMJ-D?