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Tooth Grinding and Facial Pain

Psychotherapy has helped me enormously, but I still grind away every night.
—a 25-year-old dietitian

I sometimes think the whole roomful of people can hear my jaw pop.
—a 36-year-old actor

Grinding teeth and pain in the jaw, joint, teeth, and face often occur together. They may or may not occur with other TMJ symptoms such as headaches or neck stiffness. When the cause of these symptoms is unknown or incorrectly diagnosed, patients can be subjected to various treatments that seldom relieve the problems.

GRINDING TEETH

Bruxism is the medical name for grinding the teeth. Also, although few people associate it with bruxism, clenching the teeth is included in the medical definition. Clenching teeth is a natural response to stress in many animals, including humans. Bruxism can be directly related to TMJ, either as a trigger for the spasms or as a result of the discomfort.

Even though bruxism can be destructive to the teeth, it is not abnormal in all situations. In children it is not only natural for some tooth grinding to occur, it is desirable. The teeth in a child's mouth often fit together poorly, and bruxing is necessary to refine the gearing parts of the teeth into a more normal scheme.

Typically, newly erupted front teeth have three bumps, called mamelons. In adults, the mamelons are rarely visible, because they have been worn off in the childhood grinding process. The only adults with mamelons have an "open bite," which means that the front teeth don't touch each other, and the wearing off of the mamelons doesn't take place.

Parents usually needn't worry if their children are grinding their teeth, even if the noise made by the bruxing keeps the entire household up at night. Any potential damage from the bruxing should show up in normal dental visits. As the child matures, the excessive bruxing usually disappears.

RESULTING PROBLEMS

Later in life, bruxing may become a way of getting rid of tension, anxiety, or nervousness. (It still can keep a household awake all night, while the sleeping person grinds away.) During waking hours, people relieve stress by clenching more than by grinding. A tooth-gearing problem may act as a trigger for the bruxing, which can result in muscle spasms in the Lateral pterygoids and, therefore, may lead to painful symptoms.

In adults, bruxing can also damage the teeth and the supporting structures as well as produce painful symptoms. People with abnormal gearing of the teeth are unconsciously trying to grind away what doesn't fit well in their mouths. Unfortunately, the person rarely grinds in the primary area, that is, where the teeth conflict the most. Rather they shift to other areas and grind those teeth out of proper gearing. This happens because teeth that do not gear correctly are neurologically sensitive. This sensitivity may not produce pain, however. The body protects itself in ways the person is not conscious of. This protective mechanism will lead the person to grind elsewhere in the mouth. A dentist can observe that some patients have ground their teeth just about everywhere except where the primary interference exists.

MOUTH GUARDS

Ellen Rogers was referred by a psychiatrist because of intermittent but severe headaches. She had also been grinding her teeth for so long that they were about half the height of normal teeth. She is by no means the only patient treated for TMJ whose teeth looked like tiny stubs as a result of bruxing. Ms. Rogers had a severe tooth-gearing problem and a full array of other symptoms, including neck pain, vertigo, and pain around her ears.

At her examination, she displayed a device she'd been using at night, similar to an athletic mouth guard. This device makes sense in that it keeps the teeth apart and prevents further damage to them. However, the mouth guard can hold the jaw in an unnatural and arbitrary position, which can then trigger further muscle spasms and TMJ symptoms.

Mouth guards are not recommended for TMJ treatment simply because the jaw isn't set in a natural position. Sometimes the patient gets lucky, and this arbitrary position may be proper for the jaw. In those few cases, symptoms will subside. But for far more patients, symptoms are exacerbated. Several patients have reported more severe morning headaches after using mouth guards than before using them.

TOOTHACHES

Ms. Rogers miraculously didn't have tooth pain along with the physical damage to the teeth, probably because the wear had taken place over a long period of time. Sometimes the mouth will wear itself into a position that the body can accommodate.

At other times, bruxism can go along with un-diagnosable tooth pain, which is another symptom of TMJ. While this isn't always the case, people who are aware that they sometimes grind their teeth at night shouldn't be surprised if they have toothaches or jaw pain for which no apparent cause can be found.

There are numerous reasons for tooth pain, including decay, injury, a dying nerve in the tooth, an abscess, or a sinus infection. The reasons for tooth pain in a TMJ patient can be more complicated. Because a tooth has nerve material and tissue, it can become inflamed and swollen. Pain and sensitivity to cold are also early symptoms of a dying tooth. A dentist examining a patient will listen to the patient, X-ray the tooth, and tap the tooth with an instrument. Even though nothing is visible to indicate it, the symptoms point to a dying tooth. While other causes of pain are easily diagnosed by a dentist or a physician, in patients with toothaches caused by TMJ, the diagnostic process can be baffling.

TRAVELLING PAIN

A patient once came to me for a routine check-up, and before I'd even had a chance to examine her, she told me that the previous year she'd had five root canals. When I questioned her further, she said that the root canal series had begun when one tooth caused her a great deal of pain. There was no decay or injury to the tooth, and it was eventually concluded that the tooth must be dying. A root canal was done; this was a logical, if not necessarily correct, diagnosis and treatment.

This treatment for a dying tooth wasn't unusual, except that a few weeks after the treatment was complete, she was back in the dentist's office complaining of pain in another tooth. The dentist repeated the same diagnostic sequence, and the patient had another root canal. This continued to happen until she'd had five of these procedures. Unfortunately, the pain still travelled from tooth to tooth.

Sometimes the pain will migrate around the mouth more quickly, and the patient tells the dentist that pain in one tooth went away in a few days, but came back someplace else—often, but not always, in the tooth directly above. Patients have been referred for psychological counselling because of migrating tooth pain. Since nothing appears to be physiologically wrong with each painful tooth, the cause seems to be psychological.

Most often migrating tooth pain is actually a result of the tooth-gearing problem. A cycle of hitting or banging the tooth is taking place. When a tooth is hit or banged over a period of time, the nerve in the tooth becomes inflamed. To protect that tooth, the jaw changes position to prevent the contact that caused the tooth to become inflamed and painful. Unfortunately, another tooth may then take the brunt of the hitting or banging, and it, like the first tooth, may become sensitive. The pattern can repeat itself indefinitely until many teeth have gone through a mysterious pain cycle. In many cases, this results in a mouth full of root canals. With older people, because the dental care available in their youth was less sophisticated than that available today, the painful teeth may have been removed instead.

"Hitting" or "banging" a tooth is a subtle process. No one consciously bangs a tooth. But in a patient who is grinding or clenching, the tooth may be taking the brunt of unnatural pressure, so the body unconsciously changes the clenching pattern.

REFERRED PAIN

The issue of tooth pain is further complicated because pain in a tooth can actually be "referred pain" from anywhere in the face or other areas of the body. Nerves send information along certain pathways. We don't know all the reasons for referred pain, but we know some directions pain might travel. For example, spasms in the Lateral pterygoid muscles cause pain behind the eye. Similarly, pain in a tooth may be referred from some other place.

Problems having nothing to do with TMJ or dental status can cause referred tooth pain. Sinus problems, for example, may cause pain in the upper back teeth. The roots of the molars and the bicuspids sometimes intrude into the sinus cavities, separated by only a thin layer of bone and/or sinus membranes. Allergies may also cause tooth pain, often because environmental and food allergies cause inflammation in the sinuses.

Because we now know that mysterious or undiagnosed tooth pain can be caused by TMJ, this condition should be added to the list of possible causes for tooth pain. But because TMJ patients have the same dental problems as everyone else, problems such as decay, injury to the tooth, and abscess should be investigated thoroughly, too.

FACIAL PAIN

Facial pain is another symptom that can be quite mysterious and difficult to diagnose. Pain in the face is sometimes experienced along with a headache. People frequently say, "My head hurts so much that my face is in pain, too." Many people consider a pain in the head normal, but pain in the face spells alarm. Actually facial pain can be referred pain from a tooth problem, a sinus problem, or from an injury to the head.

There is also a condition called tic douloureux, which is a facial pain syndrome. It is characterized by intense short-lasting pain, and has a trigger point in the face. A person with this problem may not have any pain until this trigger point is touched. Patients with tic douloureux will actually shave or apply makeup around that trigger point. This is quite different from the facial pain associated with TMJ. Facial pain that is caused by TMJ problems usually lasts longer and does not have a particular point that triggers the pain. TMJ and tic douloureux can exist together. In these patients it seems that, as with migraines, TMJ triggers the problem to be more frequent and severe.

An occasional patient suffers only facial pain or perhaps one or two other TMJ symptoms. A few have facial pain with the cycle of bruxing and tooth pain, leading to a confirmation of a dying- tooth diagnosis. It isn't unusual for a patient to have facial pain when a tooth is abscessed.

PAIN AND NOISE IN THE JAW AND JOINT

Pain along the jaw should be distinguished from pain felt in the joint itself. Jaw pain is common when people have dental problems, and it sometimes accompanies bruxing. But it is also a symptom of a heart attack, and a person experiencing sudden jaw pain should not assume it is a dental concern or TMJ.

Pain felt in the joint itself can also have numerous causes. Sometimes the pain is accompanied by a popping or a clicking in the joint. This popping or clicking sound is rarely associated with pain. The source of the noise is the cartilage disc that protects the bones of the joint by preventing the bones from touching each other. When functioning normally, the disc is intact and moves smoothly and in a coordinated fashion with the jaw as it goes through its range of motion.

But if the cartilage disc becomes uncoordinated for any reason, it will slip out of position, producing a popping sound, and then making another popping sound as it moves back in. The disc can be out of its normally smooth co-ordination for many reasons—loose ligaments, lack of co-ordination in the muscles, a tear in the disc, or displacement.

Some patients never experience this symptom—it is common but by no means universal. Some people report this popping only when they open their mouths very wide, as in yawning or taking a bite of a large sandwich. The jaw also may lock at these times. The popping or clicking sound can be loud and bothersome. It should always be evaluated, because it can indicate damage to the joint or the cartilage disc.

These popping or clicking sounds are different from the sounds produced in other joint- derangement conditions such as arthritis. Joint derangement from arthritis makes a crackling, gritty sound, somewhat like sand in a gear. Often the patient can hear it, and the examining clinician can hear it with a stethoscope. In some cases, the sounds are loud enough to be heard by someone standing close to the patient.

This crackling or gritty sound indicates damage to the joint. This kind of damage can cause pain, and in keeping with the idea of referred pain, it's possible that damage to the joint may cause other symptoms such as headache.

However, in most TMJ patients, symptoms that seem to be related to the joint itself are not caused by the joint. They are actually caused by the muscle spasms most often seen in patients with joint popping or pain. The joint can't cause the muscle to go into spasm directly, and the ultimate cause is the tooth-gearing problem.

As will be discussed in Chapter 11, surgery is often considered the solution for people whose symptoms are directly connected to the joint itself. However, when muscle spasms are present, it is advisable to put off such drastic treatment until there is an attempt to relieve the pain with the standard treatment approach as it is most often successful.

Each of the symptoms described can occur alone or together with the more common symptoms—headaches, neck and shoulder pain and stiffness, etc. There are people with all of them and people seeking help with only one that manifests in a severe and debilitating way. Some symptoms appear to be related to the teeth and the jaw mechanism itself, but there are two other symptoms to be discussed which seem, on the surface, to have nothing whatever to do with a gearing problem in the teeth.