Dental Decay (Cavities)

What is a cavity?

A cavity is a hole in the tooth resulting from decay. Dental decay occurs when acids present in the mouth erode or wear down the enamel (the hard external layer of the tooth). While anyone can develop cavities, appropriate oral hygiene and routine dental cleanings help prevent them. Tooth cavities are also referred to as dental caries.

Types of cavities

Cavities can develop on any surface of the tooth. Common types of dental decay and where they develop include:

• Smooth surface: This slow-developing cavity dissolves tooth enamel and can often be prevented or even reversed with good oral hygiene. This type of decay usually occurs between the teeth of individuals in their 20s.
• Pit and fissure decay: These cavities develop on the top surfaces of the chewing teeth. They can also occur on the front sides of the rear teeth. Typically, pit and fissure decay begins during adolescence and advances rapidly.
• Root decay: This type of decay mostly develops in adults with receding gums. When gums recede, they expose the roots of the teeth to acid and plaque. Root decay is challenging to prevent and treat, so it is important to consult a dentist about seeing a periodontist if you are susceptible to gum recession.

Symptoms

In most cases, tooth decay affecting the outer enamel surface doesn’t cause any pain or noticeable symptoms. Symptoms are more likely to occur when decay progresses into the dentin and pulp.

Symptoms of dental decay include:

• Bleeding gums or other indications of gum disease
• Bad breath or an unpleasant taste
• Facial swelling
• Toothache or mouth pain
• Tooth sensitivity to cold or hot foods and drinks

Tooth decay stages

Cavities are likely to affect all layers of the tooth. These are the five main stages of tooth decay:

1. Demineralisation: This first phase is characterised by small, white, chalky marks on the tooth as a result of mineral breakdown in the enamel.
2. Enamel decay: If not treated, decay advances and continues to erode the enamel, leading to visible cavities (holes) at this point. White spots might also turn light brown.
3. Dentin decay: The layer located just under the tooth enamel is known as dentin and is softer compared to the enamel. Once bacteria and plaque reach this layer, cavities develop more quickly. At this stage, teeth may become sensitive, and spots might also turn darker brown.
4. Pulp damage: The pulp is the innermost tooth layer, comprising nerves and blood vessels that carry nutrients and keep the tooth alive. If dental decay reaches this layer, it can cause pain, gum reddening, and swelling around the tooth. Spots on the tooth might become dark brown or black.
5. Abscessed tooth: If not treated, deep cavities can lead to infections, resulting in a pocket of pus formation at the tooth root tip (periapical abscess). Symptoms might include pain radiating to the jaw or face, facial swelling, and swollen neck lymph nodes. At this point, the abscess is likely to spread to nearby tissues and other body areas. Rarely, the infection can progress to the brain or bloodstream (sepsis).

Causes

The main causes of cavities are:

• Plaque formation: Plaque, a sticky film of bacteria, develops on the teeth. An interaction of starches and sugars from food with plaque can produce acids that wear down the enamel.
• Poor oral hygiene: Not brushing and flossing teeth properly causes plaque to accumulate and attack the teeth with acids.
• Frequent snacking and sipping: Frequently eating acidic or sugary foods and drinks throughout the day provides a continuous fuel source for bacteria to thrive.
• Dry mouth: Saliva helps wash away food particles and neutralise acids. A dry mouth or lack of saliva is likely to increase the possibility of dental decay.
• Certain health conditions: Health problems such as acid reflux and eating disorders causing recurrent vomiting can expose teeth to stomach acids.
• Bacteria transmission: Cavity-causing bacteria can spread from person to person by sharing items like utensils and toothbrushes, among others.

Risk factors for cavities

These factors are likely to increase the likelihood of developing cavities:

• Dry mouth or xerostomia. Some conditions, such as Sjögren’s syndrome, or drugs like antidepressants, can lead to dry mouth.
• Frequently eating sugary, starchy foods and drinks, as well as snacking between meals.
• A family history of cavities.
• Gum recession.
• Prior radiation treatment for cancers of the head and neck.

Diagnosis

Dental decay diagnosis often involves the following:

• Visual examination: This entails examining the teeth for any noticeable signs of cavities.
• Dental X-rays: These enable dentists to detect decays that are invisible to the naked eye, such as those under fillings or between teeth.
• Probing: This can be done using dental instruments to look for soft areas in the enamel indicating decay.

Treatment Options

Treatment for cavities is often determined by the severity of the condition. Common treatment options are:

• Fluoride: During the earlier stages of tooth decay, fluoride treatments can help repair impaired enamel. This process, known as remineralisation, can reverse initial signs of cavities. A prescription mouthwash and toothpaste might be necessary, along with fluoride treatments conducted at the dental clinic.
• Dental fillings: Once a hole develops in the tooth, the dentist will repair the damage by drilling out the decayed tissue and filling the hole. Dental fillings can be made of composite resin (a tooth-coloured material), gold, or silver amalgam.
• Root canal therapy: This therapy alleviates pain caused by advanced tooth cavities. Endodontists, specialists in issues affecting the tooth root, typically conduct the procedure. Root canal treatment involves the removal of the tooth pulp and filling the canals and pulp chamber with a specialised filling material. Sometimes, a dental crown may also be required to reinforce the affected tooth.
• Tooth extraction: When root canal therapy is not an option, the dentist may suggest tooth extraction. A dental bridge or implant to replace an extracted permanent tooth may be necessary, and your dentist will inform you of the suitable options.

Complications

If left untreated, dental decay can cause several complications, such as:

• Severe tooth pain: Prolonged decay can lead to significant discomfort and pain.
• Infection: Bacterial infections can form in the tooth and nearby tissues, leading to abscesses.
• Tooth loss: Advanced decay can impair the structure of the tooth, necessitating extraction.
• Gum disease: Dental decay may lead to gum disease affecting the supporting structures of the teeth.
• Spread of infection: Infections resulting from cavities may spread to other body parts, causing more severe health problems.

Prevention

Preventive measures for dental decay include:

• Proper oral hygiene: Brush your teeth at least twice a day using fluoride toothpaste and floss daily to remove food particles and plaque.
• Healthy diet: Reduce consumption of sugary and acidic foods and drinks, and eat a balanced diet full of minerals and vitamins.
• Routine dental visits: Frequent check-ups and professional teeth cleanings aid in early detection and treatment of cavities.
• Use of fluoride: Fluoride toothpaste and mouth rinses help strengthen tooth enamel and prevent decay.
• Sealants: Dental sealants can be applied to the chewing surfaces of the rear teeth to protect against cavities.
• Chewing sugar-free gum: Gum chewing promotes saliva production, which helps neutralise acids and wash away food particles.

Outlook/Prognosis

What can I expect if I have dental decay?

If the cavity is not treated for a long period, you may risk losing a significant portion of the tooth and require an extraction. Advanced decay can lead to a serious infection in the tooth and beneath the gums (tooth abscess), which could spread throughout the body. In rare situations, an infection from a tooth abscess may be life-threatening.

What’s the outlook for individuals with cavities?

The majority of individuals with dental decay do not experience enduring problems. Since cavities form gradually, it’s essential to get routine oral check-ups. Fluoride treatments might halt decay during its early stages. However, once the cavity reaches the root, there is a high possibility of tooth loss or a painful abscess (infection).

Living With

When should I call a dentist?

Consider making an appointment with your dentist if you notice any of these signs:

• Bleeding gums
• Trouble chewing
• Signs of infection
• Swollen face
• Mouth pain or toothache

What questions should I ask my dentist?

You should ask these questions during your appointment with the dentist:

• What caused my cavity?
• What treatment option is best for this cavity?
• How can I reduce the risk of developing additional cavities?
• Should I watch out for signs of complications?
• Which dental health products do you recommend?

Additional Common Questions

What does a cavity look like?

In the initial stages, cavities are difficult to see and may appear as small, white, chalky spots on the tooth enamel. As the cavity progresses, you might notice brown or black marks around the tooth.

Cavities vs. stains

Cavities and stains can both lead to tooth discolouration, and the two can easily be confused. In general, cavities have a darker colour than stains. Stains often affect multiple teeth. However, if you notice a single small spot on one tooth, it’s likely to be a cavity. Contact your dentist immediately if you suspect a cavity, as prompt treatment is crucial.

What does a cavity feel like?

This depends on the severity of the cavity. For example, a minor cavity affecting only the enamel will not be felt at all. However, when decay advances to the inner tooth layers, you might experience discomfort or become sensitive to hot, cold, or sugary substances. While tooth sensitivity does not always indicate a cavity, it’s advisable to have it checked by a dentist.

What happens if you have tooth decay for a long time?

Over time, minor cavities can develop into larger ones. As decay progresses, it impairs the deeper tooth layers, leading to pain, infection, and eventually, tooth loss. Timely treatment is important for maintaining long-term dental health.

Can a cavity heal on its own?

Yes. During the very early stages, it’s possible to reverse a cavity. Tooth enamel can repair itself. If the cavity is minor and hasn’t progressed past the enamel, you might remineralise the tooth using fluoride treatments and improved oral hygiene. However, once the cavity reaches the dentin, a filling, crown, or other dental repair will be required.

If a cavity hurts, is it too late?

A painful cavity indicates that the decay has progressed to the innermost tooth layers. At this stage, dental intervention is necessary. Timely treatment can help save the tooth. Most dentists prefer to preserve natural teeth, but if the cavity leads to an abscess or significant damage, extraction may be required. Your dentist will inform you about the available treatment options.

A Note from MD.co.uk

Schedule an appointment right away if you notice any signs of dental decay. Your dentist will examine your tooth and suggest the ideal treatment option. Catching tooth decay at its initial stage could mean you won’t require a filling, which is why seeking prompt care is highly essential. Dental appointments may be stressful, particularly if you aren’t sure of what to expect. However, establishing treatment with a trusted provider can help you overcome the anxiety of sitting in the dental chair. The dentist will give you tips on how to brush and floss to prevent new cavities and maintain a healthy smile for years to come.