These acids attack the teeth for 20 minutes or more after food is eaten.

A cavity (hole) occurs when the calcium in the tooth enamel has been removed by repeated acid attacks. The enamel can no longer repair itself through the natural remineralization process. A cavity needs treatment to save the tooth and to prevent pain and infection.

Gum disease (gingivitis or periodontal disease) is an infection that affects the gums and other tissues supporting the teeth. It is most common in adults, but also affects children.

If plaque is not removed every day by brushing and flossing, it builds up and causes the gums to become red, swollen and bleed easily. Healthy gums do not bleed. Bleeding is a common early sign of gum disease and means that brushing and flossing practices need to be improved.

Plaque hardens and turns into tartar (calculus). Tartar collects around the gum line and makes a great place to trap more plaque. This makes gum disease more likely to happen. You cannot remove tartar by brushing and flossing. You need to visit the dental office to have the tartar removed professionally.

If gum disease is not treated early, it can get worse. The infection moves down the tooth and under the gums, and can eventually destroy the bone underneath. The teeth may become loose and fall out or have to be removed.

Remember to watch for these early signs of gum disease:

• red, shiny or puffy gums
• bad breath, bad taste
• gums that bleed easily and may be tender

Studies have suggested that periodontal (gum) disease may be a risk factor in heart disease, stroke, bronchopneumonia and premature or low birth rate babies.