“When I wear it at night I rarely wake up with the headaches I used to have”. I hear this comment frequently from patients who have been given a dental parafunction-control appliance. Parafunction means jaw movements that are outside of our normal day to day motions (chewing, swallowing, talking etc). Parafunction often occurs at night when we sleep but can also occur during our awake times.
Have you ever caught yourself clenching your teeth together during a stressful moment? These are the clenching or grinding movements that dentists look for the signs of in your check-ups. In studies where muscle activity of the jaw muscles is measured, it has been found that, while asleep, people are able to clench with over 30% more force than the strongest clench they can do while awake.
These parafunctional movements can cause damage to a number of structures:
Teeth: Teeth can become worn or even fractured (we see this daily in our practice). Teeth can also become mobile with bone loss around them (an increase in periodontal disease).
TMJ: The TMJ’s or Temporomandibular Joints, in front of the ears, can have internal damage that builds up with time. This damage can produce clicks, pops, grating noises or limited movement (not being able to open as wide as you were once able). This damage can be painless or very painful.
Muscles: The muscles that control our jaws and face can become overworked and fatigued. Muscles in this fatigued state can form “trigger points”. These trigger points are painful nodules within the muscle itself. The points themselves can be painful but they can also refer pain to other sites. Referred pain means pain that is felt somewhere other than where the actual trigger point is located. This is often where the headaches originate from. It is estimated that ninety percent of all headaches are these “muscle tension” headaches.
The original reason for parafunction can be very complex to diagnose. We are all a combination of genetic information through our parents and their parents. Tooth size, jaw size and jaw development are one manifestation of this variation. Very few of us have an ideal balance of tooth size and jaw size. Rather, our bites and our tooth alignment are a compromise; our teeth fit in as best they can to the faces we were given. Breathing passages and processes which affect their development can also restrict proper development of our jaws as children. Allergies, swollen tonsils and adenoids can force a child to mouth breathe while sleeping. This causes the tongue to drop down so the child can breathe. Having the tongue improperly placed restricts the palate from developing properly-the upper jaw becomes narrow with a high palate. This then limit’s the teeth ability to fit together properly. It’s believed that this lack of fitting together properly can cause parafunction. Periods of stress in our lives can also initiate parafunctional activity.
The complexity of the head and neck is amazing. There are sixty-six pairs of muscles involved in moving our head and neck, talking and chewing! If anything is not functioning properly, a chain of effects can occur far from the original problem. Thus we look for symptoms such as pain in the ear, buzzing in the ear, headaches, tearing of the eyes, neck pain, shoulder pain, numbness or tingling of the fingers. These can all be caused by a malposition of your teeth and jaws.
These methods of diagnosis and even the topic itself represents a significant change in dentistry, one that presents a more holistic approach. If you have signs or symptoms of parafunctional activity or if you have frequent headaches investigate the dental component.
Dr. Larry Hill practices in Nanaimo. In September 2008, he traveled to Nepal as a volunteer dentist.