Dental Cavities

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Dental cavities

Alternative names

Caries; Tooth decay; Cavities - tooth
Definition

Cavities are holes that damage the structure of teeth.

Causes, incidence, and risk factors

Tooth decay is one of the most common of all disorders, second only to the common cold. It usually occurs in children and young adults but can affect any person. It is the most important cause of tooth loss in younger people.

Bacteria are normally present in the mouth. The bacteria convert all foods -- especially sugar and starch -- into acids. Bacteria, acid, food debris, and saliva combine in the mouth to form a sticky substance called plaque that adheres to the teeth. It is most prominent on the back molars, just above the gum line on all teeth, and at the edges of fillings. Plaque that is not removed from the teeth mineralizes into tartar. Plaque and tartar irritate the gums, resulting in gingivitis and ultimately periodontitis.

Plaque begins to accumulate on teeth within 20 minutes after eating (the time when most bacterial activity occurs). If this plaque is not removed thoroughly and routinely, tooth decay will not only begin, but flourish.

The acids in plaque dissolve the enamel surface of the tooth and create holes in the tooth (cavities). Cavities are usually painless until they grow very large inside the tooth and destroy the nerve and blood vessels in the tooth. If left untreated, a tooth abscess can develop. Untreated tooth decay also destroys the internal structures of the tooth (pulp) and ultimately causes the loss of the tooth.

Carbohydrates (sugars and starches) increase the risk of tooth decay. Sticky foods are more harmful than nonsticky foods because they remain on the surface of the teeth. Frequent snacking increases the time that acids are in contact with the surface of the tooth.

Symptoms
Toothache -- particularly after sweet, hot, or cold foods and drinks
Visible pits or holes in the teeth
Signs and tests
Most cavities are discovered in the early stages during routine checkups. The surface of the tooth may be soft when probed with a sharp instrument. Pain may not be present until the advanced stages of tooth decay. Dental x-rays may show some cavities before they are visible to the eye.

Treatment
Destroyed tooth structure does not regenerate. However, the progression of cavities can be stopped by treatment. The goal is to preserve the tooth and prevent complications.

In filling teeth, the decayed material is removed (by drilling) and replaced with a restorative material such as silver alloy, gold, porcelain, or composite resin. Porcelain and composite resin more closely match the natural tooth appearance, and may be preferred for front teeth. Many dentists consider silver amalgam (alloy) and gold as stronger, and these materials are often used on back teeth. There is a trend to use high strength composite resin in the back teeth as well.

Crowns are used if decay is extensive and there is limited tooth structure, which may cause weakened teeth. Large fillings and weak teeth increase the risk of the tooth breaking. The decayed or weakened area is removed and repaired. A covering jacket or "cap" (crown) is fitted over the remainder of the tooth. Crowns are often made of gold, porcelain or porcelain fused to metal.

A root canal is recommended if the nerve in a tooth dies from decay or from a traumatic blow. The center of the tooth, including the nerve and blood vessel tissue (pulp), is removed along with decayed portions of the tooth. The roots are filled with a sealing material. The tooth is filled and a crown may be placed over the tooth if needed.

Expectations (prognosis)

Treatment often preserves the tooth. Early treatment is less painful and less expensive than treatment of extensive decay. Anesthetics -- local (novacaine), nitrous oxide (laughing gas), or other prescription medications -- may be required in some cases to relieve pain during or following drilling or other treatment of decayed teeth. For those who fear dental treatment, nitrous oxide in combination with anesthesia may be preferred.

Complications
tooth abscess
fractured tooth
discomfort or pain
tooth sensitivity
inability to bite down on tooth
Calling your health care provider

Call your dentist if you have a toothache.
Call your dentist for a routine cleaning and examination if you have not had one in the last 6 months to 1 year.
Prevention Return to top

Oral hygiene is necessary to prevent cavities. This consists of regular professional cleaning (every 6 months), brushing at least twice a day, and flossing at least daily. X-rays may be taken yearly to detect possible cavity development in high risk areas of the mouth.

Chewy, sticky foods (such as dried fruit or candy) are best if eaten as part of a meal rather than as a snack. If possible, brush the teeth or rinse the mouth with water after eating these foods. Minimize snacking, which creates a constant supply of acid in the mouth. Avoid constant sipping of sugary drinks or frequent sucking on candy and mints.

Dental sealants can prevent cavities. Sealants are thin plastic-like coating applied to the chewing surfaces of the molars. This coating prevents the accumulation of plaque in the deep grooves on these vulnerable surfaces. Sealants are usually applied on the teeth of children, shortly after the molars erupt. Older people may also benefit from the use of tooth sealants.

Fluoride is often recommended to protect against dental caries. It has been demonstrated that people who ingest fluoride in their drinking water or by fluoride supplements have fewer dental caries. Fluoride ingested when the teeth are developing is incorporated into the structure of the enamel and protects it against the action of acids.

Topical fluoride is also recommended to protect the surface of the teeth. This may include a fluoride toothpaste or mouthwash. Many dentists include application of topical fluoride solutions (applied to a localized area of the teeth) as part of routine visits.



Regular Dental Visits
Q: How often should a child see the dentist?

A: The American Academy of Pediatric Dentistry recommends a dental check-up at least twice a year for most children. Some children need more frequent dental visits because of increased risk of tooth decay, unusual growth patterns or poor oral hygiene. Your pediatric dentist will let you know the best appointment schedule for your child.

Q: Why visit the dentist twice a year when my child has never had a cavity?

A: Regular dental visits help your child stay cavity-free. Teeth cleanings remove debris that build up on the teeth, irritate the gums and cause decay. Fluoride treatments renew the fluoride content in the enamel, strengthening teeth and preventing cavities. Hygiene instructions improve your child's brushing and flossing, leading to cleaner teeth and healthier gums.

Tooth decay isn't the only reason for a dental visit. Your pediatric dentist provides an ongoing assessment of changes in your child's oral health. For example, your child may need additional fluoride, dietary changes, or sealants for ideal dental health. The pediatric dentist may identify orthodontic problems and suggest treatment to guide the teeth as they emerge in the mouth.

Q: What happens in a dental check-up?

A: The pediatric dentist will review your child's medical and dental history. He or she will gently examine your child's teeth, oral tissues, and jaws. The teeth will be cleaned and polished, followed by the application of a fluoride solution.

Your pediatric dentist won't talk just to you about dental health, he or she will talk to your child with easily understandable words, pictures, and ideas. Your child will be motivated to take responsibility for healthy smile.

Q: Will X-rays be taken at every appointment?

A: No. Pediatric dentists, acting in accord with guidelines from the American Academy of Pediatric Dentistry, recommend X-rays only when necessary to protect your child's dental health.For example, X-rays maybe needed to diagnose tooth decay or abnormalities. Or, they may be required for orthodontic treatment. Your pediatric dentist will discuss the need for X-rays with you before any are taken.

Q: How can I help my child enjoy good dental health?

A: The following steps will help your child be part of the cavity-free generation:

Beware of frequent snacking
Brush effectively twice a day with a fluoride toothpaste
Floss once a day
Have sealants applied when appropriate
Seek regular dental check-ups
Assure proper fluoride through drinking water, fluoride products or fluoride supplements


Dental Cavities

Dental cavities or caries is one of the most common of all disorders.

It is an infection caused by a combination of carbohydrate-containing foods and bacteria that live in our mouths.

The bacteria are contained in a film called "plaque". Plaque begins to accumulate on teeth within 20 minutes after eating. If the plaque is not removed thoroughly and routinely tooth decay will occur.

Although there are many different types of bacteria in our mouths, only a few are associated with cavities

Streptococcus mutans, Lactobacillus casei and acidophilus, and Actinomyces naeslundii are some of them

When these bacteria find carbohydrates, they consume them to produce acids. The acids demineralize the hard part of the tooth (enamel and dentin) and eventually reach the pulp chamber.

Cavities are most prominent on the back molars, just above the gum line on all teeth, and at the edges of fillings.

The common symptoms of caries are:

1. Increased sensation to cold and/or sweet foods or beverages
2. Pain only when deeper layers are affected.
3. Weakening of the tooth

Treatment of a cavity generally consists of two steps:

1. Removing the decayed portion of the tooth under local anesthesia a high-speed dental drill is used to remove the decay and prepare the tooth for the filling.
2. Rebuilding the missing tooth structure with a suitable filling material