How Dental Cavities Develop (And What Treatment To Expect)

Despite taking the best possible care of teeth and gums, it is highly likely that dental cavities will become an issue at some time in life. Dental care and hygiene play an important role in avoiding this all-too-common dental problem — but cavities can form for a number of reasons, some of which are unavoidable.

Cavities form when the surface of the tooth, the enamel, is damaged. The affected area is weakened — and this allows small holes to develop, plus bacteria penetrating into the tooth’s core. Also called “caries” or “tooth decay”, dental cavities are one of the world’s biggest dental health issues.

Cavities can affect people of all ages although they are more prevalent in young children, teenagers and the elderly.
A cavity will not heal itself and only get worse over time, giving rise to toothaches, infections and, eventually, tooth loss. A cavity can be readily treated by a dentist — but early detection of the problem is vital to avoid an extraction or needing to have the tooth replaced.

Causes and Symptoms

Dental cavities should be treated as early as possible — and it is important to recognize the underlying causes and early symptoms of the condition. Although a cavity may develop due to physical injury, it is usually a result of improper cleaning leading to plaque and tooth decay.


A cavity forms when the tooth begins to decay and this decay advances in stages:

Plaque Build-Up. Plaque is a sticky, clear substance that coats the surfaces of the teeth. It occurs due to the breakdown of starch and sugar which quickly attracts bacteria.

If not removed properly and regularly by brushing and flossing, the plaque builds up and hardens along and under the gum line to form tartar. This makes the plaque extremely difficult to remove and provides a perfect breeding ground for bacteria.

Plaque Attack. Plaque is acidic and this acid attacks and erodes the protective dental enamel on the tooth’s surface. Tiny openings appear, and the acid and bacteria progress deeper into the tooth. Once the acid and bacteria reach the inner dentin, which connects directly to the tooth’s nerve endings, decay becomes more rapid and tooth sensitivity can be expected.

Internal Destruction. As the acid and harmful bacteria reach deeper into the heart of the tooth, the destruction continues — as the tooth’s inner pulp becomes infected. The pulp swells up due to the infection and, with no room to go, exerts pressure on the nerves causing pain, discomfort, toothache and jaw pain.

Once this stage has been reached the tooth is virtually dead and will require urgent treatment by a dentist who can provide guidance on how best to treat the problem.

Symptoms of Tooth Decay

As plaque begins to accumulate it often goes unnoticed as it causes no pain. It is usually only when the damage is done (or well under way) that physical symptoms may be noticed.

Visible and physical symptoms include:

  • Noticeable holes in the teeth
  • Discoloration of the teeth
  • Tooth sensitivity
  • Pain while eating or biting
  • Pain when drinking or eating hot, cold, sweet or sour drinks and foodstuffs
  • Toothaches
  • Painful teeth and/or jaw

By the time any, some, or all of these symptoms appear there is a significant chance that a cavity is already developing or has formed. Regular dental check-ups can greatly lower the risk for dental cavities — and early intervention is far preferable to simply letting the situation deteriorate.

Risk Factors

Anyone can suffer a cavity at any time but there are some categories of people that may be more susceptible including those who:

  • Overindulge in sweet, savory and sugary foods and drink
  • Frequently snack between meals
  • Do not clean the teeth correctly after eating or drinking
  • Suffer with dry mouth
  • Do not have fillings or dental appliance checked and replaced when necessary
  • Suffer from an eating disorder like bulimia or anorexia
  • Lack sufficient fluoride
  • Suffer with excessive heartburn

The position of a tooth can also make it more difficult to clean — which means plaque is more likely to accumulate. This is also the case with damaged fillings or dental braces, which are breeding grounds for bacteria if not properly cleaned and maintained.


When caught in the very early stages, it may be possible to treat dental decay with a mouthwash — or to varnish the tooth with a protective covering. In most cases, however, cavities require fillings. Fillings are made from either amalgam or glass composite.

Having a filling is a routine procedure and can be divided into four steps:

  1. The gum and nerves under and around the affected tooth are numbed with the use of a local anesthetic.
  2. The dentist uses a drill and other dental devices to remove all decayed matter in the center of the tooth.
  3. The resulting hole (cavity) is cleaned and filled with the selected material and any rough edges smoothed off.
  4. The dentist uses a special blue light to seal the tooth and prevent reinfection.

In the most severe cases, where the decay has destroyed the pulp at the center of the tooth, it may be necessary to undergo root canal treatment. This is a more complicated (and expensive) procedure but has the distinct advantage of saving the natural tooth and avoiding an extraction.

As a last resort, the dentist may recommend extracting the damaged tooth and replacing it with a false tooth or crown. Again, this is an expensive alternative to fillings — and saving the natural tooth should be of paramount importance as this is the best possible outcome.
Dental fillings remain the best solution for treating cavities, but an even better one is to avoid tooth decay altogether — by following a good dental health regimen and looking after the teeth and gums properly!

Dr Siddharth Wandrekar - Practice principal (GDC No. 170074)

BDS – India 2004, MSc Prosthetic Dentistry 2007 (London), MJDF Royal College of Surgeons England

Sidd has been with Brunel Dental Practice since 2011 and took over the practice in September 2016 after the previous principal retired.

Sidd qualified in 2004 from one of the prestigious Universities in India. He came to the UK and meritoriously obtained a Masters in Prosthetic Dentistry from King’s College, London. He then spent a year in a hospital environment being involved in major surgeries such as head and neck cancer, correction of jaw fractures and complex surgical removal of teeth. He moved to work as an Associate in Private and NHS practices in Scotland before joining Brunel Dental Practice.

Sidd enjoys dentistry because he can help everyone to achieve good dental health and overall well-being in a caring and comfortable environment.

He is married with two boys who keep him on his toes. He loves playing tennis and represents the local club in the regional Leagues. He loves to travel and visit offbeat places. He also has a keen interest in current affairs.

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