Tooth decay

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at March 9, 2016
StartDiseasesTooth decay

Tooth decay, which is also called cavities and caries, is the result of bacteria in the mouth creating acid that breaks down the tooth either in its outer layer (enamel), middle (dentin), or center (pulp).


Definition & Facts

Bacteria that builds up in the mouth is known as plaque and can cause acidic erosion of the teeth when the bacteria feeds on various sugars and carbohydrates in the mouth. When the bacteria eats sugars, it produces acid which then eats away at the tooth. Cavities occur when the acid dissolves a part of the enamel, creating a hole.

Tooth decay can cause complications such as tooth loss, breaking of the teeth or tooth, an infection of the tooth or gums, and inflammation of the gum around the teeth (known as gingivitis). A serious gum infection with irreversible damage can also occur and is called periodontitis. An abscess of the tooth or gums may occur and become severe.

Symptoms & Complaints

Sensitivity to hot and cold food or drinks is a common symptom of tooth decay. Due to this pain and difficulty eating, nutritional problems and weight loss can be the results. The severity of the pain can also become so intense that normal, everyday living (work duties, social lifestyles) can be inhibited.


The bacteria, whose acidic byproducts cause tooth decay, feeds on different forms of sugars: fructose (fruit sugars) and sucrose (refined sugars and simple sugars). This bacteria also feeds on refined starches (potatoes, corn) and refined grains, which are white grain products that have had the fiber, hull, and bran removed during processing. When bits of these sugars or carbohydrates are present in the mouth, the bacteria feed on them, producing acid that eats away at the teeth.

Reduced production of saliva from the salivary glands, mainly from medical conditions such as diabetes, sarcoidosis, and Sjögren's syndrome can also contribute to tooth decay. There are medications that have this effect on the production of saliva as well. These medications include antihistamines and antidepressants. Also, tobacco use carries a significant risk of tooth decay, especially smokeless tobacco due to its high sugar content.

Diagnosis & Tests

Slight toothaches should not be taken lightly, and a visit to the dentist should be in order without having to wait until a six-month examination. The diagnosis of caries, cavities or the presence of tooth decay usually is determined via X-rays, physical examinations and recent tests such as fiber optic transillumination, LED fluorescence, and laser fluorescence.

With a physical examination, the dentist can observe the teeth and look for caries, or white spots, on the teeth. A more in-depth physical examination involves a probe of the teeth with a hook-shaped instrument, or dental explorer, to feel around the teeth for crevices and holes that would distinguish cavity formations.

Treatment & Therapy

Over-the-counter pain medications as well as rinsing with salt water will help alleviate the pain of a cavity or infection. With a tooth abscess, antibiotics are administered in order to kill off the infection. If tooth decay is minimal, then a treatment using fluoride paste and a fluoride varnish will help prevent further decay.

When cavities are detected, the dentist can look to X-rays in order to view the severity of the cavity. They will then decide on the type of restoration will be needed to alleviate the problem. Cavities usually result in the removal of the decayed material and inserting a filling made of either porcelain or silver. For larger cavities, a crown or cap is used to cover the tooth.

If tooth decay has caused an infection or destruction to the root, then a root canal treatment will be done before any type of restoration is applied. However, if the tooth is destroyed enough that a root canal cannot save it, then the tooth will be removed.

With dental extraction, the patient can also opt for teeth replacement via dentures (if a significant amount of teeth are lost), a dental bridge (to fill the gap of lost teeth), or a dental implant (becomes an artificial root that is anchored into the mandible or maxilla that will support crowns, bridges or dentures).

Prevention & Prophylaxis

A six-month visit to the dentist is highly recommended as thorough cleaning and checkups will not only help keep the teeth and gums healthy but will enable the patient to know of any issues that they may tend to. Executing proper and frequent oral hygiene will help with the prevention of tooth decay; tooth brushing three times a day can help prevent tooth decay.

Also, flossing daily is recommended as it provides adequate removal of food particles left between the teeth and gums, therefore reducing the risk of infection of the gums and tooth loss. Furthermore, using an antiseptic mouth rinse during every brushing and flossing session will greatly reduce the plaque that harbor bacteria which cause tooth decay.