When I talk to someone about grinding I am usually met with the same answer, “I don’t think I grind my teeth.” To which I reply, “You’re either taking a belt sander to your teeth during the day, or grinding at night, you tell me.” The truth is; most people who grind don’t even know that they are doing it. The damage from grinding is like aging, you don’t see it happening on a daily basis. One day you look in the mirror and see a 40 year old where you expected to see a 21 year old.
Grinding is referred to, by Dentists, as Bruxisim, meaning; the habitual, involuntary grinding or clenching of the teeth, usually during sleep, as from anger, tension, fear or frustration. It originates from the Latin Bruxis: a gnashing. The word gnashing is used in the bible to explain what hell will be like, “there will be much gnashing of teeth.” Doesn’t sound very nice to me.
Teeth are not meant to touch. It sounds odd, but it’s true. They don’t touch while you speak, smile or rest. Even when you chew, your teeth only have to be close enough to mash food, not touch. An average person who does not grind will have their teeth touch only about 4 minutes in an average day. The average person who grinds only during REM sleep will have their teeth touch about 3 hours a night or 180 minutes, that is 45 times longer.
Grinding wears away your tooth structure and flattens the teeth. This flat- tening is unsightly and initially a cosmetic issue. Eventually your teeth shorten enough that your jaw starts to over close. People without teeth or with short teeth have a shorter facial appearance. The corners of the mouth become creased and you get the permanent frown look because the teeth are hidden behind the lips and the lips bunch up when your mouth is closed. Severe wear will shorten your teeth to the gum line and spaces will appear between the teeth. The material underlying your enamel is called dentin, and is much softer in composition. Once the enamel is worn away and the soft dentin is exposed, it wears at 4-5x the rate of enamel.
Why do we grind? Most habitual grinders have a personality that is charac- terized by aggressive, competitive, hurried, nervous and have a hard time handling stress. However, anger, pain and frustration can cause anyone to start showing the signs of bruxisim. It is difficult to estimate the incident of bruxisim in the general population. However, it is generally accepted that in a nor- mal population approximately 1/3 to 1⁄2 of people have significant wear from grinding.
Another part of grinding is the stress placed on the tooth itself. When lateral pressure is applied to a tooth, the tooth wants to bodily move. The boney socket surrounding your root prevents the tooth from mov- ing, so the tooth bends slightly at the gumline. The repeated bending of the tooth is much like when you bend a paperclip, eventually it starts to break in half. Another way to think of the tooth is to compare it to a candy with a hard shell and a soft flexible inner; like a Mike and Ike. When it is bent the hard outer shell flakes away revealing the soft inner core. The enamel of the tooth will begin to flake away and leave the softer sensitive dentin. We call this process abfraction. An abfraction clinically appears as a triangular notch on the front surface of your tooth, slightly below or at the gumline.
There is a competing theory that proposes that these notches are caused by tooth brush abrasion, or rigorous, hard brushing. In my professional opinion this theory is wrong. If enough force was applied with a toothbrush to notch the teeth, then the gum tissue adjacent to the tooth would also be damaged. It also does not explain how the lesions start below the gum line. If you took a tooth brush and scrubbed one spot on a piece of granite for 30 seconds twice a day it would take a long time to make a notch.
Other habits may influence tooth wear such as biting finger nails or cuticles, pencils, and chewing on your cheek or lip. Sun flower seeds, tongue rings and fishing line will also cause tooth wear especially on the front teeth. Women who do crafts and hold wire in their teeth can eventually carve a notch with the wire.
A quick comment about grinding in kids. It is normal and usually self limiting and does not progress to adult denti- tion.
Treatment for bruxisim is simple. Eliminate all stress in your life. Ok, so it’s not that simple. The treatment will involve some or all of the following: Self-care ther- apy, splint wear and/or medication. The first step is usually recognition of the habit and fabrication of an occlusal guard. The guard is an acrylic or thermoplas- tic plate that covers the upper or lower teeth and provides a smooth surface that the opposing teeth cannot gear into. Many times the slight 2-3mm opening of the mouth eliminates the trigger for the muscles to grind. If grinding does occur the acrylic is softer than your teeth so it wears away instead of your teeth. Over the counter grinding guards and soft “gummy” grinding guards are usually not suffi- cient to correct grinding. The teeth can still find purchase with grinding and clenching and cause abfraction damage.
Abfractions are treated only if they are sensitive to cold and brushing or if they show in the smile. If they are caught early enough an abfraction is best treated through a periodontal surgery to cover the exposed area and an occlusal guard. If the abfractions are too large for surgery or if you do not want surgery, then they can be fixed with white filling material in conjunction with an occlusal guard.
Some insurance companies have coverage for occlusal guards. Even if you have to pay out of pocket an ounce of prevention is worth a pound of cure. Cor- recting severely worn teeth requires extensive crown work and can cost tens of thousands of dollars.
If you have any questions about grinding, abfraction or occlusal guards please contact us today.