Your mouth is one of the most important parts of your body. It has many different functions. It allows you to

• Take in food and drink
• Breathe in air
• Start digestion, with your teeth chewing the food you eat and your salivary glands releasing saliva to help break down the food
• Speak and sing
• Show emotion, by smiling or pouting

Any problem that affects your mouth can make it hard to eat, drink, or even smile. Some common mouth problems include

• Cold sores - painful sores on the lips and around the mouth, caused by a virus
• Canker sores - painful sores in the mouth, caused by bacteria or viruses
• Thrush - a yeast infection that causes white patches in your mouth
• Leukoplakia - white patches of excess cell growth on the cheeks, gums or tongue, common in smokers
• Dry mouth - a lack of enough saliva, caused by some medicines and certain diseases
• Gum or tooth problems
• Bad breath

Treatment for mouth disorders varies, depending on the problem. If a mouth problem is caused by some other disease, treating that disease can help. It is also important to keep your mouth clean and healthy by brushing, flossing, and not using tobacco.

Canker sores are small, round sores in your mouth. They can be on the inside of your cheek, under your tongue, or in the back of your throat. They usually have a red edge and a gray center. They can be quite painful. They are not the same as cold sores, which are caused by herpes simplex.

Canker sores aren't contagious. They may happen if you have a viral infection. They may also be triggered by stress, food allergies, lack of vitamins and minerals, hormonal changes or menstrual periods. In some cases the cause is unknown.

In most cases, the sores go away by themselves. Some ointments, creams or rinses may help with the pain. Avoiding hot, spicy food while you have a canker sore also helps.

Cold sores are caused by a contagious virus called herpes simplex virus (HSV). There are two types of HSV. Type 1 usually causes oral herpes, or cold sores. Type 1 herpes virus infects more than half of the U.S. population by the time they reach their 20s. Type 2 usually affects the genital area.

Some people have no symptoms from the infection. But others develop painful and unsightly cold sores. Cold sores usually occur outside the mouth, on or around the lips. When they are inside the mouth, they are usually on the gums or the roof of the mouth. They are not the same as canker sores, which are not contagious.

There is no cure for cold sores. They normally go away on their own in a few weeks. Antiviral medicines can help them heal faster. They can also help to prevent cold sores in people who often get them. Other medicines can help with the pain and discomfort of the sores. These include ointments that numb the blisters, soften the crusts of the sores, or dry them out. Protecting your lips from the sun with sunblock lip balm can also help.

It's important to take care of your mouth and teeth starting in childhood. If you don't, you could have problems with your teeth and gums - like cavities or even tooth loss.

Here's how to keep your mouth and teeth healthy:

• Brush your teeth twice a day with a fluoride toothpaste
• Clean between your teeth every day with floss or another type of between-the-teeth cleaner
• Snack smart - limit sugary snacks
• Don't smoke or chew tobacco
• See your dentist or oral health professional regularly

What is saliva?

Saliva, or spit, is made by your salivary glands. It helps keep you and your mouth healthy. For example:

• It moistens and breaks down the foods you eat, which makes it easier for you to chew and swallow.
• It washes away small food pieces from your teeth and gums, which helps fight against tooth decay.
• It contains minerals such as calcium and phosphate, which can also help fight tooth decay.
• It contains antibodies that can fight against infections of the mouth and throat. Antibodies are proteins that your immune systemmakes to fight foreign substances such as viruses and bacteria.

What is dry mouth?

Having dry mouth, also called xerostomia, means that you don't have enough saliva to keep your mouth wet. Everyone has a dry mouth once in a while, like when you are nervous or stressed. But if you have a dry mouth all or most of the time, it can be uncomfortable. It can make chewing, swallowing, and even talking difficult. It also raises your risk for tooth decay or infections in the mouth.

What causes dry mouth?

There are many possible causes of dry mouth, including:

• Side effects of certain medicines, such as some medicines for high blood pressure, depression, and bladder-control issues
• Diseases such as Sjogren's syndrome, HIV, salivary gland disorders, and diabetes
• Radiation therapy, which can damage your salivary glands if they are exposed to radiation during the treatment
• Chemotherapy, which can make your saliva thicker and cause your mouth to feel dry
• Nerve damage, when it involves the nerves that tell salivary glands to make saliva
• Breathing through your mouth
• Use of alcohol, tobacco, or other substances

What are the symptoms of dry mouth?

The symptoms of dry mouth may include:

• A sticky, dry feeling in your mouth
• Trouble chewing, swallowing, tasting, or speaking
• A burning feeling in your mouth
• A dry feeling in your throat
• Cracked lips
• A dry, rough tongue
• Mouth sores
• An infection in your mouth
• Bad breath

How is the cause of dry mouth diagnosed?

If you have dry mouth, it's important to find out the cause. To do that, your health care provider or dentist will review your medical history, examine your mouth, and ask about any medicines you take. They may also suggest blood tests or a test that measures how much saliva you produce.

What are the treatments for dry mouth?

Treatment for dry mouth depends on the cause. For example, if a medicine is causing dry mouth, your provider or dentist may suggest adjusting the dosage or switching medicines. In some cases, they might give you artificial saliva or a medicine to help your salivary glands work better.

There are also several things you can do to help relieve your symptoms:

• Drink plenty of water
• Avoid drinks with caffeine, which can dry out your mouth
• Chew sugarless gum or suck on sugarless hard candy to stimulate saliva flow
• Avoid spicy or salty foods because they can cause pain if your mouth is dry
• Avoid alcohol and tobacco
• Using a humidifier at night
• Use a mouthwash made for dry mouth

Since dry mouth can raise your risk of tooth decay, it's important to brush and floss your teeth regularly and see your dentist at least twice a year.

If you have gum disease, you're not alone. Many U.S. adults currently have some form of the disease. It ranges from simple gum inflammation, called gingivitis, to serious damage to the tissue and bone supporting the teeth. In the worst cases, you can lose teeth.

In gingivitis, the gums become red and swollen. They can bleed easily. Gingivitis is a mild form of gum disease. You can usually reverse it with daily brushing and flossing and regular cleanings by a dentist or dental hygienist. Untreated gingivitis can lead to periodontitis. If you have periodontitis, the gums pull away from the teeth and form pockets that become infected. If not treated, the bones, gums and connective tissue that support the teeth are destroyed.

Throat cancer is a type of head and neck cancer. Throat cancer has different names, depending on which part of the throat is affected. The different parts of your throat are called the oropharynx, the hypopharynx, the nasopharynx, and the larynx, or voice box.

The main risk factors for throat cancer are using tobacco heavy drinking. Certain types of throat cancer also have other risk factors. For example, having HPV is a risk factor for oropharyngeal cancer.

Symptoms of throat cancer may include:

• A sore throat that does not go away
• A lump in the neck
• Pain or ringing in the ears
• Trouble swallowing
• Ear pain

To diagnose throat cancers, doctors may do a physical exam and history, imaging tests, and a biopsy. You may also need other tests, depending on the type of cancer. Treatments include surgery, radiation therapy, and chemotherapy. Treatment for some types of throat cancer may also include targeted therapy. Targeted therapy uses drugs or other substances that attack specific cancer cells with less harm to normal cells.

Oral cancer can form in any part of the mouth. Most oral cancers begin in the flat cells that cover the surfaces of your mouth, tongue, and lips. Anyone can get oral cancer, but the risk is higher if you are male, use tobacco, drink lots of alcohol, have HPV, or have a history of head or neck cancer. Frequent sun exposure is also a risk factor for lip cancer.

Symptoms of oral cancer include

• White or red patches in your mouth
• A mouth sore that won't heal
• Bleeding in your mouth
• Loose teeth
• Problems or pain with swallowing
• A lump in your neck
• An earache

Tests to diagnose oral cancer include a physical exam, endoscopy, biopsy, and imaging tests. Oral cancer treatments may include surgery, radiation therapy, and chemotherapy. Some patients have a combination of treatments.

Your salivary glands are in your mouth. You have three pairs of major salivary glands and hundreds of small (minor) glands. They make saliva (spit) and empty it into your mouth through openings called ducts. Saliva makes your food moist, which helps you chew and swallow. It helps you digest your food. It also cleans your mouth and contains antibodies that can kill germs.

Problems with salivary glands can cause them to become irritated and swollen. You may have symptoms such as

• A bad taste in your mouth
• Difficulty opening your mouth
• Dry mouth
• Pain in your face or mouth
• Swelling of your face or neck

Causes of salivary gland problems include infections, obstruction, or cancer. Problems can also be due to other disorders, such as mumps or Sjogren's syndrome.

Many disorders can affect our ability to speak and communicate. They range from saying sounds incorrectly to being completely unable to speak or understand speech. Causes include

• Hearing disorders and deafness
• Voice problems, such as dysphonia or those caused by cleft lip or palate
• Speech problems like stuttering
• Developmental disabilities
• Learning disorders
• Autism spectrum disorder
• Brain injury
• Stroke

Some speech and communication problems may be genetic. Often, no one knows the causes. By first grade, about 5 percent of children have noticeable speech disorders. Speech and language therapy can help.

If you have a swallowing disorder, you may have difficulty or pain when swallowing. Some people cannot swallow at all. Others may have trouble swallowing liquids, foods, or saliva. This makes it hard to eat. Often, it can be difficult to take in enough calories and fluids to nourish your body.

Anyone can have a swallowing disorder, but it is more likely in the elderly. It often happens because of other conditions, including

• Nervous system disorders, such as Parkinson's disease and cerebral palsy
• Problems with your esophagus, including GERD (gastroesophageal reflux disease)
• Stroke
• Head or spinal cord injury
• Cancer of the head, neck, or esophagus

Medicines can help some people, while others may need surgery. Swallowing treatment with a speech-language pathologist can help. You may find it helpful to change your diet or hold your head or neck in a certain way when you eat. In very serious cases, people may need feeding tubes.

Your throat is a tube that carries food to your esophagus and air to your windpipe and larynx. The technical name for your throat is the pharynx.

Throat problems are common. You've probably had a sore throat. The cause is usually a viral infection, but other causes include allergies, infection with strep bacteria or the leaking of stomach acids back up into the esophagus, called GERD.

Other problems that affect the throat include

• Tonsillitis - inflammation of the tonsils
• Cancer
• Croup - inflammation, usually in small children, which causes a barking cough
• Laryngitis - swelling of the voice box, which can cause a hoarse voice or loss of voice

Most throat problems are minor and go away on their own. Treatments, when needed, depend on the problem.

Your tongue helps you taste, swallow, and chew. You also use it to speak. Your tongue is made up of many muscles. The upper surface contains your taste buds.

Problems with the tongue include

• Pain
• Swelling
• Changes in color or texture
• Abnormal movement or difficulty moving the tongue
• Taste problems

These problems can have many different causes. Treatment depends on the underlying problem.

Acute types of coxsackievirus infections or ECHOVIRUS INFECTIONS that usually affect children during the summer and are characterized by vesiculoulcerative lesions on the MUCOUS MEMBRANES of the THROAT; DYSPHAGIA; VOMITING, and FEVER.

Increased salivary flow.

A loss of mucous substance of the mouth showing local excavation of the surface, resulting from the sloughing of inflammatory necrotic tissue. It is the result of a variety of causes, e.g., denture irritation, aphthous stomatitis (STOMATITIS, APHTHOUS); NOMA; necrotizing gingivitis (GINGIVITIS, NECROTIZING ULCERATIVE); TOOTHBRUSHING; and various irritants.

Candidiasis is an infection caused by a yeast (a type of fungus) called Candida. Candida normally lives on the skin and inside the body, in places such as the mouth, throat, gut, and vagina, without causing any problems. Sometimes, Candida can multiply and cause an infection if the environment inside the mouth, throat, or esophagus changes in a way that encourages fungal growth.

Candidiasis in the mouth and throat is also called thrush or oropharyngeal candidiasis. Candidiasis in the esophagus (the tube that connects the throat to the stomach) is called esophageal candidiasis or Candida esophagitis. Esophageal candidiasis is one of the most common infections in people living with HIV/AIDS.