Caries Control Program

Dental Caries is caused by a number of interrelated factors including bacterial ecology, frequency of fermentable carbohydrate intake, unhealthy saliva and retained acid producing plaque.

How dental tooth decay happens

Tooth decay is caused by certain types of bacteria (mutans streptococci and lactobacilli) that live in your mouth. When they attach themselves to the teeth and multiply in dental plaque, they can do damage. The bacteria feed on what you eat, especially sugars (including fruit sugars) and cooked starch (bread, potatoes, rice, pasta etc). Within about five minutes after you eat or drink, the bacteria begin producing acids as a byproduct of their digesting your food. Those acids can penetrate into the hard substance of the tooth and dissolve some of the minerals (calcium and phosphate). If the acid attacks are infrequent and of short duration, your saliva can help to repair the damage by neutralising the acids and supplying minerals and fluoride that can replace those lost from the tooth. However, if you have many of these bacteria, or your saliva is defective, then the amount of tooth mineral that is lost by the attacks of acid is too great and cannot be repaired. This is the start of tooth decay and leads to cavities.

Methods of controlling tooth decay

1. Diet

Reducing the number of sugary and starchy foods, snacks, drinks or lollies can help reduce the development of tooth decay. That doesn't mean you can never eat these types of foods, but you should limit their consumption particularly when eating between meals. A good rule is 3 meals per day and no more than 3 snacks per day. (It is the frequency of the sugary insults, not the quantity).

2. Remineralisation

To rebuild the tooth minerals that have been lost or eroded, you need calcium and fluoride in that order. The structure of tooth enamel is Ca,10(ph) 6F2, so we need 10 calciums, 6 phosphates and 2 fluorides in order to add back one tooth crystal.

3. Plaque Removal

The most important thing to do at home is to clean your teeth twice daily. The purpose of cleaning the teeth is to reduce the overall level of bacteria in your mouth as well as cleaning the biting surfaces and the sides of the teeth, facing the tongue and cheeks. Brushing is also effective in reversing and preventing gingivitis, but in order to control and prevent tooth decay, you must use a toothpaste containing fluoride. However, in order to clean between the teeth, other oral hygiene aids must be used daily, e.g. floss or interdental brushes.

4. Saliva

Saliva is critical for controlling tooth decay. It neutralises tooth decay acids and provides minerals and proteins that protect the teeth. If you cannot brush after a meal or snack, you can chew some sugar free gum. This will stimulate the flow of saliva to help neutralise the acids and bring lost minerals back to the teeth. Sugar free candy and mints could also be used, but some of these contain acids themselves. These acids will not cause tooth decay, but they can slowly dissolve the enamel surface over time (a process called erosion). Some sugar free gums are designed to help fight tooth decay and are particularly useful if you have a dry mouth (many medications can cause dry mouth). Some gums contain baking soda which neutralises the acids produced by the bacteria in plaque.

Gum that contains xylitol as its first ingredient is the gum of choice e.g. Extra professional or Extra for kids.

If you have a dry mouth, you could also fill a drinking bottle with water and add 2 teaspoons of baking soda for each 250ml of water and swish with it frequently throughout the day. Toothpastes containing baking soda are also available from several companies.

5. Antibacterial mouth rinses:

Rinses and gels that your dentist can prescribe are able to reduce the number of bacteria that cause tooth decay and can be useful in patients at high risk of tooth decay e.g. perioguard used once a week will provide excellent killing of bad bacteria but not result in staining or bacterial resistance.

6. Fissure Sealants (Preventative Resin Restorations)

PRRs are plastic coatings bonded to the biting surfaces of back teeth to protect the deep grooves from decay. In some people, the grooves on the surfaces of the teeth are too narrow and deep to clean with a toothbrush, so they may decay in spite of your best efforts. Sealants are an excellent preventative measure for children and young adults at risk.

Why do I get so many dental cavities?

Tooth decay or cavities occur when plaque bacteria produce acid that lowers the pH of the mouth thus dissolving the mineral components in the enamel surface of the tooth. Unfortunately, some people are more prone to decay than others.

Your diet plays a large role in the development of tooth decay. A diet that is high in sugary foods produces more bacterial plaque, therefore increasing your chance of developing cavities.

Factors determining the cariogenicity of food

1. Frequency of exposure

Each exposure of the teeth surfaces to sucrose in a meal or snack increases the amount of acid on the teeth causing the pH of the mouth to drop, increasing the chance of the teeth to decay. The amount of sucrose is not as important as when and how often the teeth are exposed.

2. Duration of exposure of teeth

The longer food remains in the mouth, the more exposure of the teeth to plaque acids thus causing the greater chance of decay. For example, sucking on a lolly will create more chance of decay than eating an apple. Sweet food taken after brushing and flossing before retiring are not cleared readily because salivary flow decreases during sleep therefore providing longer duration of the sweet food on the teeth.

3. Consistency of food

Soft, sticky foods cling to the teeth and encourage food and debris accumulation thus leading to increased amounts of bacterial plaque. On the other hand, firm, fibrous foods like uncooked vegetables tend to clear away loose debris.

There are several ways that you can reduce the frequency of decay

1. Choose snacks wisely

Try eating snacks that are lower in sugar. Some snacks such as cheddar cheese, nuts, vegetables and popcorn are anti-cariogenic and do not cause decay. Choosing snacks such as these will reduce your incidence of decay.

2. Brush your teeth after every meal and floss once a day

Brushing your teeth within 30 minutes after eating will increase the pH of your mouth and clear away debris thus reducing the incidence of decay. Flossing every day removes the plaque that builds up between your teeth, reducing the chance of interproximal decay.

3. Avoid eating and drinking between meals throughout the day

Try to avoid long exposure to the teeth to sugary drinks and candy. Avoid sucking on lollies and drinking sugary beverages all day long. If drinking coffee or tea, avoid adding sugar. Avoid drinking energy drinks during exercise as they are high in sugar. Drink water instead.

4. If you cannot brush between meals or after snacks try sugarless chewing gum.

Chewing sugarless gum will stimulate saliva flow. As saliva acts as the body's natural clearance of sugar, chewing sugarless gum will increase saliva flow and reduce your chance of developing decay.

Treatment:

Normally treatment of decay is to remove the decay, fill the cavity, promote good daily home care and use a fluoride rinse to prevent further decay. However, if you have a high rate of decay, then controlling your diet is also important.