Dentistry

Cavities

What Causes a Cavity?

Your mouth is a busy place. Bacteria - tiny colonies of living organisms are constantly on the move on your teeth, gums, lips and tongue.

Having bacteria in your mouth is a normal thing. While some of the bacteria can be harmful, most are not and some are even helpful.

Certain types of bacteria, however, can attach themselves to hard surfaces like the enamel that covers your teeth. If they're not removed, they multiply and grow in number until a colony forms. More bacteria of different types attach to the colony already growing on the tooth enamel. Proteins that are present in your saliva (spit) also mix in and the bacteria colony becomes a whitish film on the tooth. This film is called plaque, and it's what causes cavities.

Braces

How Do Braces Work?

Having straight teeth is important. Teeth that are crooked or out of place (misaligned) affect the way a person chews and talks and how their smile looks. Because they have unnatural spaces, crooked teeth are harder to clean and are more likely to have cavities.

In some cases, crooked teeth can affect the way the jaws line up and can cause pain and discomfort.

Severe Malocclusion

One method to correct this is to have Orthodontic treatment (or braces and retainers as they are sometimes called). Orthodontic treatment works by exerting a gentle pressure over time to straighten teeth that are growing, or have already grown, out of place.

Braces have three basic parts:
1) Brackets - brackets that are attached to each tooth
2) Bonding or band - the material that attaches the bracket to the tooth
3) Arch Wire - a thin metal wire that runs from bracket to bracket

Braces have come a long way from the "train track" look of years ago. Today, many orthodontic patients can get braces that attach to the backs of the teeth, or use transparent brackets.

A retainer is a custom-made, removable appliance that helps keep teeth in their new, straightened position after braces have been removed. Retainers can also be used to treat more minor orthodontic problems.

Prevention

Fluoride:How Does It Work?

Fluoride is a natural element that can be found in many things, like the water we drink and the food we eat. Decades ago, scientists began to notice that children who lived in places where fluoride occurred naturally in the water, had fewer dental cavities.

Fluoride that is absorbed by your body is used by the cells that build your teeth to make stronger enamel. Topical fluoride - fluoride that is applied to the outside of the enamel - makes the crystals that form enamel more durable. Tooth enamel crystals that have fluoride are much more resistant to acid. They are less likely to breakdown and cause the tooth surface to become porous.

If your dentist recommends a fluoride treatment during your next dental visit, you'll be receiving topical protection. The fluoride your dentist puts in your mouth will help make the crystals in your tooth enamel stronger. Always use a toothpaste with fluoride. Look for the Canadian Dental Association seal of approval on the toothpaste tube in your bathroom.

For an experiment on the protective power of Fluoride, check out the Healthy Teeth Dental Experiments Page!

Teeth and Gums

Tooth Growth and Development

What's the difference between "baby" teeth and permanent teeth? At between six and ten months of age, most infants begin to get their "baby" teeth.

The Central Incisors (front middle teeth) usually come in first, and then teeth begin appearing on either side and work their way back to the second molars. By the time a child has reached three years old, most of the "baby" teeth should be present.

The process begins to repeat itself when the child is about seven years old. The Central Incisors fall out first and are replaced by permanent teeth. By the age
of 21, most people have all of their permanent teeth.

"Baby" teeth are important because they hold the place for permanent teeth and help guide them into correct position. "Baby" teeth play an important role in the development of speech and chewing.

Experiments

The Power of Fluoride

This experiment simulates the protection
power of Fluoride.

What you'll need:

1 bottle of Fluoride rinse solution (available from your dentist, local dental supply company and some pharmacies)
2 eggs
1 bottle of white vinegar
3 containers

What to do:
Pour four inches of Fluoride rinse solution into one of the containers and then place an egg in the solution. Let it sit for five minutes. Remove the egg. Pour four inches of vinegar into each of the remaining two containers. Put the egg that has been treated with the Fluoride into one container of vinegar and the untreated egg in the other container of vinegar.

What will happen:
One egg will start to bubble as the vinegar (an acid) starts to attack the minerals in the egg shell. Which egg do you think will start to bubble?

No Butts About It

Tobacco and Healthy Teeth Don't Mix

Do you smoke? If you don't, you probably know some friends or see other students at school who do. Too many young people today are getting addicted to tobacco, and the results are showing up in their mouths.

Smoking or using smokeless "chewing" tobacco can make you four times more likely of developing oral cancer (especially on the rise in women as more younger girls take up smoking) - and it's not just something that older adults get anymore.

On top of cancer, tobacco causes:

bad breath
stained teeth
bone loss
shrinking gums
mouth sores
decreased senses of taste and smell
poor healing of mouth sores
hairy tongue
leukoplakia

Young people who think that smokeless "chewing" tobacco is somehow safer than lighting up are putting themselves at terrible risk of illness. Chewing tobacco releases a variety of chemicals into the body and often causes mouth sores, cracked and bleeding lips and gums, and can lead to cancer of the throat, mouth and gums.

How does Tobacco
affect oral health?

Tobacco contains many substances known to be cytotoxic (destructive to your body's cells and tissues). Smokers have more calculus (hardened dental plaque) than nonsmokers, and heavy smokers have more calculus than light smokers. The Nicotine in tobacco causes something called vasoconstriction (narrowing the blood vessels). Blood circulation - certainly an important thing! - has been shown to decrease by as much as 70% in your mouth during the smoking of a cigarette. Tobacco smoking, furthermore, also affects your body's immune responses (defense system).

New studies are even showing the possibility that second-hand tobacco smoke (the smoke from someone else's cigarette) causes periodontal disease (gum disease).

Sugar? In tobacco?

We all know that sugar is a major cause of tooth decay. More than one-fifth of the content of some brands of smokeless "chewing" tobacco is sugar, and causes a much greater risk of developing cavities.

Cut the Sugar, Grab the Milk!

Hey, what's in that School Lunch or Snack?

Each time you eat a snack containing sugar or starch (carbohydrates), the resulting acid attack on your teeth can last up to 20 minutes, and a lot of snacks and drinks contain sugar. How much sugar? A single can of pop contains up to 10 teaspoons of sugar, and if you think that natural sugar (like the sugar in raisins or other fruit) is better for your teeth it’s not. Sugar is sugar, and the average Canadian consumes over 40 kilograms of sugar each year! Click here for a list of how much sugar your favorite snack might contain.

Beat the Clock - foods that are eaten during a meal usually pose less of a threat to teeth because of the additional saliva produced during mealtime eating. Saliva helps to wash food particles from your mouth and lessen the damage from acid.

Brush & floss those teeth - toothbrushing is important, and you should brush twice a day. Did you know that if you don’t floss, you miss cleaning up to 35% of each tooth? If you’re not sure how to floss, just ask your dentist.

Stock up on Dairy Products - yogurt and cheese, milk and milk products contain things that are good for your teeth. Everything that’s made from milk is a good source of calcium - an essential nutrient for the development of bones and teeth. Some scientific studies have shown that eating cheese might actually help to protect your teeth from cavities by preventing something called demineralization (the loss of important calcium in your teeth).