II. Long-term bruxism often causes changes of appearance, in at least three different ways.
First, unappealing, worn out looking teeth.
Second, shorter teeth. As a result, when the mouth is closed, the upper and lower jaws are nearer than they used to be, and so are the nose and chin. The skin now may bag below the eyes and curl around the lips, causing the lips to seemingly disappear (Schlott, 1997). The chin recedes, and the person looks comparatively old.
The young man (image to the right) has normal teeth. By middle age (middle frame), bruxism flattened this man’s teeth and changed his appearance somewhat. By old age (right frame), the change is even more remarkable (Source: Gelb, 1994, p. 227).
Third, bruxism involves excessive muscle use, leading to a build-up or enlargement (hypertrophy) of facial muscles, especially those of the jowl (where the masseter muscle–the muscle that raises the lower jaw and enables closing the jaws–is located). In long-term bruxers, this build-up may lead to a characteristic, square-jaw, appearance. Some patients resort to removing part of the masseter muscle by surgery or injections of toxic materials to reduce muscle size and thus partially regain their former, more aesthetically pleasing, looks (Mandel & Tharakan, 1999; Rijsdijk et al. 1998).
Images to the right and above: Facial appearance of a 13-year-old bruxer with left masseteric hypertrophy (arrow on right). Source: Mandel & Tharakan, 1999. Masseter muscle. Source: Life Art
III. Symptoms of long-term bruxism (Bubon, 1995):
- Jaw tenderness
- Jaw pain
- Fatigue of facial muscles
- Neck aches
- Hearing loss
Our body is not built to sustain, night in and night out, the tremendous pressures of bruxing. The teeth, as we have seen, are affected, but in some cases other parts of the head suffer too. We need to note, in passing, that such aches and pains are a functional, healthy, response. It’s the body’s way of sending a message: stop bruxing, or else!