How is tooth decay treated?

Romesh Nalliah
Tooth decay can be treated in a variety of ways and it depends on the extent of the decay:

1. Very minor cavities are actually reversible in the presence of fluoride.
2. Larger cavities may require a filling.
3. Very large cavities that involve the nerve have to be thoroughly evaluated by your dentist and may need root canal treatment in addition to fixing the cavity.

The important point is to have regular check-ups where your dentist can diagnose and manage cavities in the first or second category before they become so large that they need root canal treatment
Dental caries, or decay, is usually treated by removal of the decay and shaping of the remaining tooth structure to retain a filling. The filling is placed, contoured and adjusted to duplicate the shape of the natural tooth as closely as possible. When indicated, liners, sealers and/or bases are placed under the primary filling material.

A dental filling, which may be placed with a variety of materials, restores a fractured, chipped, decayed and sometimes worn tooth. When a tooth has extensive deterioration, a large filling can restore the tooth but not necessarily keep the weak areas from fracturing.

When the tooth is extensively broken down, often a crown may be indicated to provide a more secure restoration that can help to prevent fracture and further breakdown of tooth structure.
Early, or Incipient Decay, is a small bit of decalcification of enamel, in the outer layer of the tooth. These early lesions can often be treated with a prescription fluoride toothpaste, or rinse and they can reverse and not need a filling. 

Decay that moves through the enamel, into the softer, less calcified dentin, does require a restoration. Typically a small bonded filling is placed on early dentinal lesions. Bonded fillings hold the tooth structure together and allow for less tooth to be removed.

Deep decay, which moves closer to the nerve of the tooth, can be restored with a base and a filling. If the tooth is, or remains symptomatic, root canal therapy may be needed. 

Imagine that a supporting wooden beam in your home becomes infested with termites. If only a small portion of the beam is involved, the termites can be destroyed, the weakened part of the beam removed, and the beam patched and strengthened. If the entire beam is infested with termites, it will need to be completely replaced. Similarly, a tooth can become weakened by bacteria. If the infected part of the tooth is limited to a small amount, the soft part of the tooth can be removed and then patched with a filling. If the entire tooth is destroyed, it should be removed and replaced with an artificial tooth.

Tooth decay should be treated by a dentist. The severity of the decay will determine the treatment. Small cavities can generally be treated with fillings. Larger cavities may require root canals and crowns. Severe cavities may require extraction of the tooth. Your dentist can best advise you as to what treatment would be best for your tooth with a cavity.

Tooth decay is usually removed while the tooth is anesthetized. Decay, or 'caries,' is removed by various methods including hand instrumentation, by the use of dental "drills" and with the use dental lasers. The depth or size of the decay will often determine which means is best utilized.

Once the caries is removed, the tooth needs to be restored to normal function. The type of restoration depends on how much of the tooth needs to be replaced following caries excavation. If a small cavity remains, it can be restored most commonly with silver or tooth colored/composite fillings. If it is a larger cavity, it may require an inlay, an onlay or even a crown.

The best treatment of all is to prevent the disease from happening in the first place. This is accomplished through proper oral hygiene and regular visits to the dentist.
All the prior answers offer the reader a great base of information. Let's take that a step farther, to what I'm seeing clinically.

We have a great number of patients, who experience an unexpected and rapid onset of tooth decay with different medications prescribed by their physicians. It's essential you list all medications with your dentist's health history form, and they review this with you on a frequent basis. Why?

Medications seemingly unrelated to dental care may have a profound impact on dental cavities. The big problem is dry mouth. Your natural saliva is a protection mechanism against tooth decay. When certain medicines like blood pressure medications or psychotherapeutic medicine are used, a side effect may be reduced saliva flow. Your physician may not even be aware. So, please review all prescribed medicines with your dentist.

This includes illegal drugs as well. There is a profound link between methamphetamine use and "meth mouth", which often results in a severe increase of dental decay.

Therefore, the treatment of tooth decay goes beyond restoration of teeth. It goes to addressing the causes, which generated the tooth decay. 
Abraham Speiser

Tooth decay is the destruction of tooth by a bacterial disease called dental caries. Caries destroys teeth. If caries is diagnosed EARLY, i.e. before loss of tooth structure results in a hole in the tooth (a cavity), then caries can sometimes be “cured” using chemicals to re-calcify the affected tooth structure. Once the caries has resulted in a cavity, the treatment is to remove the caries and restore the tooth to form and function with a filling or a crown.

Dante A. Gonzales, DMD
Orthodontics & Dentofacial Orthopedics

That all depends on how deep the tooth decay is.

  • If the tooth decay is very superficial then brushing, flossing, and fluoride treatments will usually help arrest the decay and prevent a cavity from forming.
  • Once the decay has penetrated into the tooth enamel and formed a cavity then the dentist must remove the decay along with the bacteria that caused the decay. The cavity is then filled with a restorative material.
  • If the decay has penetrated not only the enamel and dentin, but also the pulp of the tooth, then a root canal is needed in order to remove the infection from the pulp.

Going to the dentist every 6 months should help prevent decay from progressing into the dentin or pulp. Regular dental checkups and good oral hygiene will go a long way in preventing the need for any extensive dental work.

Tooth decay is best treated by your dentist. Decay can be prevented by brushing twice a day with fluoride toothpaste, flossing teeth once a day, eating a healthy diet and limiting snacking. Drinking fluoridated water also helps prevent tooth decay. Visit your dentist regularly for professional cleanings and an oral examination.

Continue Learning about Cavities


Cavities are tiny holes in your teeth that have developed from decay. Left untreated, cavities will get larger, and can cause toothache and possible loss of teeth. Anybody can get a cavity, but you put yourself at greater risk if ...

you don't brush regularly, or frequently consume sweets or sugary drinks. Your dentist can help prevent cavities with fluoride treatments, and can find them by taking pictures (X-rays) of the teeth. Once found, the dentist may treat your cavity with a filling or if extensive, with a crown. If there has been an extensive infection, other treatments, including antibiotics or a root canal surgery may be indicated.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.