Oral and dental health

What is it?

The CDC defines oral health as the health of the teeth, gums and the whole oral and facial system.

The World Health Organization (WHO) lists the main oral diseases as dental caries (tooth decay), gum disease (gingivitis and the more advanced periodontitis), tooth loss, cancers of the lip and oral cavity, and tooth and mouth injuries caused by accidents.

NIDCR explains that tooth decay develops when bacteria in the mouth turn sugars and starches from food and drink into acid that dissolves the minerals in tooth enamel. It may begin as a white spot that can be reversed before an actual cavity (hole) forms in the tooth. Young children may develop "early childhood caries", which usually starts in the front teeth.

NIDCR and MedlinePlus describe gum disease as an infection that usually begins as "gingivitis" (redness, swelling and easy bleeding), which is generally reversible with regular brushing, flossing and professional teeth cleaning. If left untreated, it can progress to "periodontitis", in which the gums pull away from the teeth and pockets form that may become infected; in severe cases the bone and tissues supporting the teeth may be damaged and teeth may be lost.

WHO states that oral diseases affect about 1 billion people, with a prevalence of about 20% in children up to 12 years of age, and that there are less common conditions such as cleft lip and palate, with a global prevalence of between 1 in 1,000 and 1 in 1,500 births.

Why it matters

The CDC says that oral health affects eating, speaking, smiling and expressing emotions, and that poor oral health can cause pain, poorer school performance, lost productivity and a lower quality of life.

The CDC estimates US productivity losses from untreated oral disease at about US$46 billion a year (in 2015 dollars), in addition to about 34 million school hours and about 92 million work hours lost each year because of emergency and unplanned dental care.

The CDC links oral health with general health: poor gum health may make it harder to control blood sugar in people with diabetes. WHO says that diabetes and gum disease are linked in both directions.

WHO says that oral diseases disproportionately affect poor and socially disadvantaged people across all income levels and ages, that direct out-of-pocket costs are a major barrier to treatment, and that oral care is among the main causes of catastrophic health spending.

According to WHO, cancers of the lip and oral cavity are more common in men and older people and more deadly in men, and they rank 13th among the most common cancers worldwide.

Key points

According to WHO: untreated tooth decay in permanent teeth is the most common health condition worldwide, severe gum disease affects more than 1 billion cases, and complete tooth loss averages about 7% at age 20 and over, rising to 23% at age 60 and over.

Cancers of the lip and oral cavity: about 389,846 new cases and 188,438 deaths worldwide in 2022 (WHO).

In the United States, according to the CDC: 57% of children and adolescents (12–19 years) have had decay in their permanent teeth, and 90% or more of adults (20 years and over) have had decay at some point, while only 42% of children (6–11 years) have dental sealants on their permanent teeth.

According to the CDC, fluoridated tap water is associated with about 25% less tooth decay in children and adults.

In a healthy mouth, gum pocket depth is between 1 and 3 mm; deeper pockets may indicate gum disease, according to NIDCR.

Mild gingivitis is usually reversible with daily brushing and flossing and regular professional cleaning, but if left untreated it can progress to periodontitis, which may cause tooth loss, according to MedlinePlus and NIDCR.

How to put it into practice

Brush your teeth twice a day with a fluoride toothpaste; WHO recommends a fluoride concentration of between 1,000 and 1,500 parts per million, and the CDC, NIDCR and MedlinePlus all recommend brushing twice a day with fluoride toothpaste.

Clean between your teeth daily with dental floss or another interdental cleaner; this is recommended by the CDC, NIDCR and MedlinePlus, and NIDCR notes that alternatives include an interdental brush, wooden or plastic picks, or a water flosser recommended by a dental professional.

Cut down on sugars: WHO recommends reducing free sugars, eating more fruit and vegetables, and making water the main drink. The CDC and NIDCR also advise limiting foods and drinks rich in sugars and starches and reducing how often you have them between meals, as they feed the bacteria that cause decay. See also healthy nutrition.

Quit all forms of tobacco: WHO includes tobacco cessation in the prevention of oral diseases, and NIDCR describes smoking and tobacco use as the most important risk factor for gum disease. See also quitting smoking.

Reduce alcohol use: WHO includes reducing alcohol use among the measures for preventing oral diseases.

See your dentist regularly: the CDC recommends visiting a dentist for a check-up and professional cleaning at least once a year, with extra visits if your health care provider recommends them. Some oral diseases cause no pain or visible signs until a late stage, so regular professional check-ups matter.

Ask your dentist about sealants for children's permanent teeth; they cover the chewing surfaces and help prevent decay for years, according to NIDCR and the CDC.

Protect your face and teeth during sport or when riding bicycles and motorcycles by wearing suitable protective equipment, to reduce facial injuries, according to WHO.

At community level, the CDC states that fluoridating tap water and school-based sealant programmes are public health measures that reduce tooth decay, especially for people who may not have easy access to dental care.

Special groups

Children: according to the CDC, 57% of children and adolescents (12–19 years) in the United States have had decay in their permanent teeth, and only 42% of children (6–11 years) had sealants on their permanent teeth. NIDCR notes that young children may develop "early childhood caries", which usually starts in the front teeth.

Pregnancy: according to the CDC, pregnant women are more prone to gingivitis because of hormonal changes, and one in four women of childbearing age has untreated tooth decay. The CDC confirms that routine and emergency dental care is safe at any stage of pregnancy, and recommends seeing a dentist during pregnancy. The CDC also notes that children of mothers with high levels of untreated decay or tooth loss are more than 3 times as likely to develop decay.

Older adults: WHO states that complete tooth loss rises to about 23% in people aged 60 and over, compared with an average of about 7% worldwide at age 20 and over, and that oral cancers are more common in older people. NIDCR lists dry mouth, saliva and salivary gland disorders, and taste disorders as oral health topics in older adults, along with the relationship between diabetes and oral health. See also healthy ageing.

People with diabetes: the CDC says there is a link between diabetes and gum disease, which is a leading cause of tooth loss, and that treating gum disease significantly improves blood sugar control compared with no treatment or routine care alone. The CDC states that adults (20 years and over) with diabetes are 40% more likely to have untreated tooth decay, and that those aged 50 and over are 46% more likely to have fewer than 20 teeth and 56% more likely to have 8 or fewer teeth, compared with people without diabetes. The CDC also notes that about 60% of US adults with diabetes saw a doctor in the past year without seeing a dentist. WHO says that diabetes and gum disease are linked in both directions, and that excess sugar intake is causally linked to diabetes, obesity and tooth decay.

Risks and cautions

Modifiable risk factors according to WHO: excessive intake of free sugars, tobacco use in all its forms, alcohol use, and poor oral hygiene.

NIDCR states that smoking and tobacco use are the most important risk factor for gum disease, and that they also delay healing and reduce the success of gum treatment. Other risk factors for gum disease according to NIDCR include older age, diabetes, genetic factors, stress, conditions such as rheumatoid arthritis, heart and blood vessel disease, obesity and HIV/AIDS (and its medicines), and hormonal changes in girls and women; gum disease is also more common and more severe in men, according to NIDCR.

NIDCR states that children with primary immunodeficiency disorders are about 10 times as likely to develop gum disease.

Signs of gum disease that warrant seeing a dentist, according to NIDCR and MedlinePlus: red, swollen or tender gums that bleed easily, gums that pull away from the teeth so that the teeth look longer, loose or sensitive teeth, pain when chewing, and persistent bad breath.

WHO says that oral diseases disproportionately affect poor and socially and economically disadvantaged people, that the distribution of oral health workers is uneven, and that primary oral health care services are limited in many countries.

Oral cancer: WHO states that it is more common in men and older people and more deadly in men, and that the human papillomavirus (HPV) is a growing cause of oral cancers in young people in North America and Europe.

Limits of this information

Many of the figures here (decay rates in children and adults, sealants, and figures on diabetes, pregnancy and oral health) come from US data from the CDC, and rates may differ in other countries.

This page does not cover in detail less common conditions such as noma or cleft lip and palate; it limits itself to what WHO's general oral health page says about them.

This page does not specify an age for a child's first dental visit; ask a paediatric dentist or primary care doctor about the right timing. The care or treatment that suits you is decided by you and your dentist according to your situation.

Details of anaesthetic agents, gum treatment medicines and types of dental filling are deliberately not given here; the choice of treatment is decided by your dentist according to your situation.

The emergency sign below (facial swelling and fever with toothache) is taken from a general description of how a dental abscess develops in a single source (NIDCR), and this page does not cover dental emergencies in detail. Consult your dentist or your country's health authority if in doubt.

Common questions