by Dr Y.L.M
My husband has been suffering pain at the angle of his jaw for a long time now, ever since he broke his jaw in a rugby accident when he was a teenager. It would come on especially after he’s had a cold. He went to the doctor who said he had temporo-mandibular disorder (TMD). I have never heard of this before. What is it?
Temporo-mandibular disorders are disorders pertaining to the temporo-mandibular joint.
This is the joint on each side of your head, the part where your lower jawbone is attached to your skull. It joins the upper jaw bone (maxilla) with the lower jaw bone (mandible). This joint allows your mouth to open and therefore for you to open your mouth, talk, bite, chew food and yawn.
The temporo-mandibular joint is a hinge or a sliding 'ball-and-socket' joint, and it is extremely complex because the lower jaw's rounded edges need to glide in and out of the joint socket whenever you talk or chew, which for some people can most of the time!
It is also known to be one of the most frequently used joints in the body.
The parts of the joint where the bones attach are naturally covered with cartilage. The two bones making up the joint are separated by a small disc to absorb shock and also to keep the movement smooth.
TMD is actually a very common disorder. Around 5 to 15% of people in the US have it, and it is more common in women than men, especially between the ages of 30 to 50.
Why do people get TMD? Is it because they talk too much?
It is jaw clenching and teeth grinding that are more likely to cause TMD than too much talking!
If anything happens to disrupt the structure or function of the temporo-mandibular joint, you may get TMD. Think of the components of the joint – the disc, the cartilages, the bones of the joint itself and even the muscles surrounding and attaching to them.
Any of these components can be damaged by :
(1) Trauma – a blow to the side of your jaw during sports or fighting. If you had an old fracture, the misalignment that results from improper healing might lead to TMD.
(2) Inflammation – when your joint's cartilage is affected by arthritis, such as rheumatoid arthritis.
(3) Erosion of the disc.
(4) When the muscles surrounding the joint are fatigued from being overworked, like if you do have a habit of grinding your teeth or clenching your jaw.
Teeth grinding and jaw clenching actually cause wear and tear on the cartilage of the joint. You may not even be aware you are doing this because a lot of people do it in their sleep. It usually takes your spouse to tell you or a dentist may notice you have a lot of wear and tear on your teeth. People under a lot of stress may constantly do this.
(5) Another common habit causing wear and tear on your cartilage is perpetual gum chewing or fingernail biting. So beware!
(6) Dental problems and misalignment of your teeth. Chewing on only one side of the jaw can lead to TMD.
(7) If you frequently hold the telephone receiver between your head and shoulder, you can also get TMD.
(8) Congenital deformity of your facial bones.
On many occasions, the cause of TMB is not known.
My husband says that sometimes he would experience a clicking sound whenever he tries to open his mouth. Is this common?
You may experience the following with TMD :
* Pain or tenderness of your jaw, especially at its angle.
* A disturbing or aching pain in and around your ear. You might sometimes mistake this for an ear infection. This happens in 50% of patients. The ear pain is usually described as being in front of or below the ear.
* Difficulty or discomfort while chewing your food.
* A general headache. 80% of TMD sufferers complain of this.
* Pain on your face – dull and aching. 40% of people complain of this.
* Sometimes your TM joint might 'lock', causing it to be difficult for you to open or close your mouth.
* The feeling that you are not able to bite properly. When you close your mouth, you may feel that one or more of your teeth are not making clean contact with their upper or lower counterparts.
* A clicking sound or a grating sensation whenever you try to open your mouth or chew. There also should be pain associated with it. Some normal people have jaws that click when they open them – they do not necessarily have TMD.
* Some people have a lot of ear symptoms associated with their TMD even though there is nothing wrong with the ear per se – such as dizziness, fullness of the ear and ringing in the ear. To this day, this cannot be fully explained, but a theory is that the muscles around your Eustachian tube (the one that connects your ear to your throat) might spasm when you have TMD.
An easy step you can do yourself to locate your TM joint is by putting your finger on the triangular structure in front of your ear. Now move your finger slightly forward and press down firmly while opening your jaw. Can you feel an immediate depression? This is your TM joint working.
If you have TMD, this simple manoeuvre can cause you considerable discomfort.
More info on TEMPOROMANDIBULAR DISORDER here.
by Dr Y.L.M