A cavity is an area of decay in a tooth, resulting from the interaction between oral bacteria and sugar and other carbohydrates in the mouth. In the course of metabolizing the sugars (and starches transformed into sugar by saliva), the bacteria create an acid that becomes part of a sticky substance known as dental plaque. Plaque clings to the tooth and begins to erode the enamel, producing holes, or cavities. Tooth enamel is the strongest material in the body, but it does not renew itself. As bacteria and the acids they form further penetrate the damaged tooth surface, a cavity enlarges to the point where it invades the dentin the bony material inside a tooth .
Diagnostic Studies And Procedures
During a routine checkup, a dentist examines each tooth with an angled mirror and metal probe to make sure that surfaces are intact. Where doubt exists, an X-ray may be taken. In addition, a complete set of dental X-rays is routinely taken every three or four years to detect any hidden problems.
If the work is expected to be extensive and painful, the dentist gives the patient the option of having an anesthetic such as Novocain injected into the gum. To prepare a tooth for filling, the dentist cleans out the cavity with a high-speed water cooled drill, sterilizes the interior, and dries it. A filling that matches the tooth is then chosen from a wide range of long lasting compounds. Unless there are unexpected complications, a simple cavity can be filled in one visit. If the cavity has extended to the dentin, the area may be injected with a calcium phosphate solution to stimulate new dentin growth. A temporary filling will be placed in the cavity, then later removed and replaced with a permanent filling. When a cavity has reached into the pulp of the tooth, the patient may be referred to a specialist, an endodontist, for root canal work. This procedure kills the nerve, eliminating pain and usually saving the tooth, which can then be cleaned out and filled as usual. If only the base of the tooth remains after extensive decay or root canal work, the dentist fills the socket of the tooth with cement and covers it with a crown. This usually takes three or four sessions because it involves laboratory work and precision fitting.
The compounds in green tea are reported to kill the bacteria responsible for causing tooth decay. The same compounds occur in sage, coriander, and thyme. A traditional temporary remedy for a toothache has been oil of cloves, but this is not recommended today because it can damage delicate gum tissue.
A diet that provides adequate calcium and other minerals is essential to building strong teeth. For this purpose, babies and young children may also be given fluoride drops with their food, especially if the local water does not contain added fluoride. Reducing sugar intake, especially sticky sweets that adhere to the teeth, helps to prevent cavities.
Hypnosis, biofeedback, and similar techniques can help people to overcome a fear of dentists. Hypnosis is also used as an alternative for patients who cannot tolerate Novocain and other anesthetics.
Good oral hygiene is the key to preventing cavities. Visiting your dentist regularly and flossing and brushing properly can prevent most decay. Toothpastes with added fluoride also help prevent cavities. However, be careful about allowing children to use extra strength fluoridated types. Eating the toothpaste can lead to fluoride toxicity. Also, pregnant women should not take fluoride supplements because it can cause tooth mottling in the child. Never allow a baby to fall asleep with a bottle of milk, juice, or other sweetened liquid because this can cause “baby bottle caries.” If a bottle is essential at bedtime, fill it with water. The application of a dental sealant on the chewing and grinding surfaces of a child’s back teeth is the best way to protect them from cavities. The procedure is usually scheduled when the permanent molars begin to appear typically between ages 6 and 8, and again at age 12.
Other Causes of Cavities
Long term use of drugs that reduce the flow of saliva, such as antihistamines, tranquilizers, and antidepressants, increase the risk of cavities. Radiation therapy of the head and neck and diseases affecting the salivary glands also contribute to tooth decay by reducing the output of saliva. Accidents that chip or break tooth enamel make the surface more vulnerable to decay.