TMJ disorders is a group of complicated problems of the jaw joint. TMJ stands for temporomandibular joint or jaw joint. This is also referred as myofacial pain dysfunction and Costen's sydnrome. Since muscle and joints work together, a problem of this joint can lead to stiffness, headaches, ear pain, bite problems, clicking sounds or locked jaws.

These are the common causes that can lead to TMJ:

1. Teeth grinding and clenching of teeth can cause an increase in the wear on the cartilage lining of TMJ. If a person continue to do this he often wakes up in the morning with jaw or ear pain.

2. Gum chewing or biting of the fingernails.
3. Problems with teeth and misalignment of the teeth. Patient who have this often complain that they have difficulty biting and they have a tendency to chew on only one side of the jaw which can lead to TMJ problems.

4. Trauma to the jaws
5. Stress can lead to unreleased nervous energy and some people often release this by either consciously or unconsciously clenching their teeth.

Symptoms of TMJ are:

1. Headache which are often felt by 80% of patients with TMJ while 40% report facial pain. The pain is usually increased when opening and closing the jaw.

2. Ear ache or pain in he ear are often the complain of about 50% of patients. The pain is usually located in front or below the ear.

3. Grinding, crunching or popping sounds which are called crepitus are common in patients who have TMJ.

4. Forty percent of the patients reports a mild dizziness or imbalance.
5. Feeling of fullness in the ear. For 33% of patients, they describe muffled, clogged or full ears.
5. Tinnitus or ringing in the ear are the complaints of some 33% of patients with TJM.

Most people have occasional episodes of TMJ but much of the time the cause is unknown. It is more common in women than men, so it may have a hormonal component. Grinding teeth due to stress, eating hard candy or chewing gum, or physical trauma can cause tmj but it can also be secondary to certain conditions such as rheumatoid arthritis.

There are some self-care steps one can take to ease the pain; avoiding hard candy and chewing gum which can make the condition worse, OTC pain meds or hot/cold packs. Sleeping on your side will help too; sleeping on the back lets the jaw go slack.

Here's a resource about Jaw Pain. Please refer the link below for information.

Source : http://www.whatpain.com/jaw-pain.html

Causes of TMJ are the following-
• Muscle tension
• Teeth grinding
• Dental bite misalignment
• Poorly fitted dentures
• Partial jaw dislocation
• Jaw injury
There are many symptoms of TMJ disorder. The disorder can and does manifest itself in a variety of ways, such as:
• Eye Pain and Eye Problems
• Head Pain, Facial Pain
• Ear Pain, Ear Problems
• Throat Problems
• Neck and Shoulder Problems