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Expected Dental Challenges - 2-9 Years Old

During the 2-9 year old period, the child has only deciduous (baby) teeth. Baby teeth are fragile.


Enamel is the protective outer coating of teeth, and it is thin on baby teeth. This means that if a cavity starts, it gets big quickly. The most common place for a cavity in a baby tooth is between the last two molars or between the two upper front teeth. If you notice a cavity, get it looked after at the dentist’s office soon. Baby teeth are needed. The adult teeth “know” where to erupt by guiding themselves into position using the roots of the baby teeth. Having a bunch of baby teeth out when a child is very young virtually assures the need for braces later. The least expensive way to take care of cavities is to use a toothbrush and floss and avoid getting them in the first place. Now is the time to get into the tooth brushing habit after waking up and before going to bed every day.

Baby teeth will begin to be replaced by adult teeth starting at about six years old and all will be replaced by about twelve years old. Spaces usually develop between the teeth before the new teeth arrive. Grinding at night (officially called bruxing) is not at all uncommon as the jaws grow to accommodate the much larger adult teeth. Researchers do not expect decay in the majority of children in this period, but we have seen that many young people get cavities. A diet with sweets and or fruit several times a day without brushing soon afterwards each time is usually the cause of these early cavities. Keep in mind that a filling on a permanent tooth placed at six years old will usually have to be replaced even if everything goes perfectly (with the person’s oral hygiene) at least every 20 years. 6, 26, 46, 66, 86. That’s five fillings on that same tooth in the child’s lifetime, so you can see why early decay in permanent teeth is something to be avoided if possible.

Many teeth have deep groves on their biting surface. Teeth are more likely to get a cavity during the first six months they are in the mouth because of the depth of the groves on some people’s teeth. Sometimes the grooves are so deep there is actually little or no protective coating on the tooth (enamel) at the deepest part of the grooves. A sealant acts as the protective coating nature sometimes neglects to place properly on some molars. When molars are erupting, it is a good idea to get a dentist to have a look at them and give an opinion on whether the young person would benefit from having the grooves sealed with plastic. The technology of sealants has changed in the last few years as researchers have discovered that decay grows in the grooves if it has inadvertently been sealed into the tooth when a sealant is placed. Many young people can benefit from sealants. Ask your dentist if your child is one of them.

At this point in history, we have several tools everyone can use to reduce the chance of tooth decay: Toothbrush, floss, professional cleaning, and fluoride. You at home also have another powerful tool to aid in reducing the chance of tooth decay, and that tool is diet. Fluoride is a powerful tool to use in fighting the development of tooth decay. Young people in the 2-9 year old period (actually birth to 9 year old period) benefit significantly from fluoridated water. The body concentrates fluoride in the bones and teeth, so even though municipal water in fluoridated communities is 1 part per million or slightly less, it has a powerful effect on developing teeth. Research is quite conclusive that exposure to fluoride in water on a daily basis in this birth to 9 year old period reduces tooth decay throughout life by about 35%. The effect continues throughout life even if the person moves out of the fluoridated area after 9 years old. Eating fluoridated toothpaste is common in this period and should be avoided because too much fluoride when the teeth are forming can cause unsightly permanent white or even brown spots to develop on the forming teeth. Just a pea sized bit of toothpaste is plenty on Junior’s toothbrush. Use of fluoridated toothpaste instead of non fluoridated toothpaste or no toothpaste at all reduces tooth decay by another about 30%, but its effect is short lived. It lasts a few weeks or months on the teeth rather than lasting a lifetime like the fluoride introduced by fluoridated water. As far as diet, sweets should be a treat and not a staple in this period. For the teeth, the amount of sugar is much less of a factor causing damage to the teeth than is the frequency of sugar intake. For example, if a child is going to eat a candy bar, it does far less damage to the teeth if it is consumed in a couple of minutes than if it is eaten bit by bit over the whole afternoon. Brushing is a good idea after eating sweets, or at least a rinse and swish with water if brushing is not possible.

- This article was written by Dr. Mike Christensen and published in the Daily Miner and News, and Enterprise. Local Kenora News Publicatons (1998-2006)

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