Dental Occlusion 101

Few things can be more uncomfortable than a jaw that is out of kilter. When you think about how your jaw is in nearly constant movement, pivoting, opening, closing, chewing, yawning, talking, it is not surprising that any small irritation can give rise to major, nearly constant, discomfort.

Just to make it clear: the lower jaw is a very unique piece of your body. It is, for example, the only joint in your entire being that crosses your midline, and the muscles on either side really only function comfortably when coordinated with their counterparts on the other side. And these muscles overlay and interact with all the muscles of your head and neck, so any tension or disharmony in one muscle or group can eventually transfer to every other muscle. So it is very important that the muscles function as they should, going from a relaxed rest position into their functional position as easily and smoothly as possible.

The ideal position for any muscle at rest is in a relaxed position, where there is no pull on the muscle. However, the muscles in your jaw are directed to place by the position of your teeth. You see, the muscles will guide your jaw to close where the greatest number of teeth hit together at the same time, which makes of course for efficient and effective chewing. The problem arises when one or more teeth are out of ideal position, so that the muscles have to torque the jaw into full closure, and then fight to hold them there. This means that the muscles are constantly working to hold the jaw where the jaw really does not want to be (due to the misaligned teeth).

And so the muscles do what muscles do: they try to wear away the point of deflection, and this creates what we call either bruxing or clenching. And eventually, the muscles will wear away the high spots by wearing away the teeth, but there will be a great deal of “collateral damage” in the process.

Our goal is to guide the jaw into the most conservative and comfortable position possible, either by selectively polishing the high spots or by repositioning the teeth, through orthodontics or restorations. To make absolutely certain of our accuracy, we use a computer to assist us in our “fine-tuning” of the bite, and confirm the endpoint by measuring the status of the primary muscles of chewing. We are the only dental office in Portland, and one of the few in the world, to use this sophisticated equipment to correct the bite, using a process called “Disclusion Time Reduction”, or DTR.

For those who seek a temporary but effective solution, we also offer Botox, to lessen the force of the facial muscles. Botox can be refreshed almost indefinitely and is very effective, but it only treats the symptoms.

The endpoint we look for is to adjust the bite so that the jaw closes easily and solidly, and that there are no interferences to block an easy slide to the side or forward.

You can easily evaluate your own mouth, in a few simple steps:

1). Bite together, quickly, and with your lips apart. If everything is hitting at the same time, there should be a loud “CHOMP” sound. If the sound of closing is muffled, or soft, or indistinct, this is an indication that you may have a deflective contact, and your muscles are hesitating because they need to compensate for this interference.
2). Rest your fingers to the outside of your upper teeth, from the canines back, and then, from full closure, slide your jaw side to side. If you feel the teeth “riding up” on one or more teeth, then this is an indication of a restrictive contact that should be corrected.
3). If there are grooves near the outer neck of the teeth, where the teeth enter the gums, or if there is a notching on the inside edge of the upper front teeth, then you may well be positioning your jaw forward whenever possible. This is a sign of a jaw being held back too far and is often because of the front teeth being pushed back, and hence restricting the lower jaw movement.

In any event, if you have any questions, we invite you to call us or visit us for an evaluation. Sometimes it is as simple as polishing an area, and the relief can be immediate and significant. But the rule of thumb is that if you feel you might have TMJ problems, you most likely do. And those problems will not resolve themselves comfortably or in a timely manner, without professional assistance.