Dry mouth, also known as xerostomia, is a condition that is caused by reduced salivary production which can have various causes. In most cases, dry mouth condition lasts for short time and can be treated by simple measures such as drinking enough amount of water daily. If dry mouth is associated with pain during chewing, swallowing, or speaking, you should consult your dentist to determine the underlying cause.
More than 90% of saliva is produced from major salivary glands (parotid, submandibular, and sublingual). The rest is produced from minor salivary glands that are scattered in the oral cavity. Salivary glands produce about 0.75 to 1.5 liters of saliva daily and it drops almost to zero during sleep. Saliva consists of 99.5% water and 0.5% dissolved components such as digestive enzymes, various proteins, calcium ions, Potassium, sodium, and antibacterial compounds. Saliva plays an important role in the maintaining of oral health.
Causes of Dry Mouth
Dry mouth can have various causes, either the production of saliva is reduced or the composition of saliva is changed. The causes of dry mouth include:
- Dehydration: dry mouth occurs frequently due to dehydration. This can occur due to insufficient fluid intake or excessive fluid loss through exercise, fever, diarrhea, or vomiting.
- Age: in old age, not only the function of salivary glands slow down but also elder people drink less often and consume drugs that may cause xerostomia as a side effect.
- Mouth Breathing: it can also occur if you breathe through your mouth, for example:
- Habitual mouth breathing
- Breathing through the nose is difficult due to allergy or cold.
- Emotional stress: dry mouth is a typical symptom of stress. Also, it frequently occurs as a symptom of depression and anxiety.
- Smoking and alcohol use: alcohol drinking and smoking or chewing tobacco can increase the risk of xerostomia.
- Radiation therapy: it involves the use of radiation in the treatment of tumors such as cancer. The using of radiation in the head and neck area often damages the salivary glands. The symptoms may include taste disturbance, permanent xerostomia, and burning mouth syndrome.
- Chemotherapy: the drugs used in chemotherapy can affect the composition of saliva and the amount of salivary flow. This effect may be temporary and the salivary flow will return to its normal volume after completing the treatment.
- Medications: many drugs affect the autonomic nervous system (ANS) which is responsible for controlling the production of saliva – ANS regulates the function of our internal organs. These drugs can cause dry mouth as a side effect, for example:
- Antihypertensive drugs.
- Sedative and hypnotics drugs such as sleeping pills.
- Antihistamines (drugs against allergies).
- Chemotherapeutic agents as a part of cancer chemotherapy treatment.
- Antiemetic drugs: drugs for nausea and vomiting.
- Psychotropic medications: such as antidepressant and antianxiety drugs.
- Medical conditions: dry mouth can be a side effect of some medical conditions such as:
- Autoimmune disease: such as Sjogren’s syndrome or HIV/AIDS. The symptoms of Sjogren’s syndrome include dry eye, xerostomia, red oral mucosa, burning tongue, and swollen salivary glands.
- Diabetes mellitus: its symptoms include frequent urination, strong thirst, xerostomia, fatigue, and headache.
- Cold: allergies, flu, cold, or sinusitis can cause inflammation of the nasal tissues which may lead to nasal congestion. The nasal congestion will lead to mouth breathing and the result is dry mouth condition.
- Sialadenosis: it is a painless, non-inflammatory, bilateral swelling of the salivary glands. It may cause a reduced salivary flow.
- Sialadenitis: it is a painful, inflammatory swelling of salivary glands, usually caused by bacterial or viral infection. It can reduce the salivary flow.
- Salivary gland tumors: malignant or benign salivary gland tumors may limit the function of salivary glands and reduce the production of saliva.
Signs and Symptoms of Dry Mouth
Dry mouth can cause unpleasant symptoms such as:
- Dry, sticky, and discomfort feeling in the oral cavity and are often associated with frequent thirst.
- Difficulty or discomfort during chewing, swallowing and speaking.
- The saliva is thick.
- Taste disturbance.
- Burning sensation in the oral cavity especially in the tongue.
- Inflammation of the oral mucosa. It makes the wearing of dentures and regular food intake often impossible.
- Bad breath.
- Mouth sores.
- Painful and dry tongue.
- Tooth mineral loss and frequent dental caries.
Complications of Dry Mouth
Saliva consists of 99.5% water and 0.5% dissolved components such as digestive enzymes, various proteins, calcium ions, Potassium, sodium, and antibacterial compounds. Saliva plays an important role in the maintaining of oral health. Dry mouth can cause some complications such as:
- Increased plaque accumulation and dental caries risk.
- Bleeding, swollen, and inflamed gums which may lead to tooth loss.
- Bad breath.
- Fungal infection and mouth sores.
- Difficulty chewing and swallowing which may lead to poor nutrition.
- Discomfort and difficulty during speaking.
- Taste disturbance.
- Burning sensation in the oral cavity.
Diagnosis of Dry Mouth
For the diagnosis of dry mouth, your dentist will examine your oral cavity and review your medical history. Also, he/she will ask you about:
- Coffee and alcohol consumption.
- Smoking habits.
- Oral hygiene habits.
- Existing or previous medical conditions.
- Do you take any medications?
Also, the dentist will ask you about existing signs or symptoms such as:
Problems with chewing, speaking and swallowing.
- Taste changes.
- Gum problems.
- Bad breath.
The physical examination is required for the diagnosis of dry mouth. During the examination, the dentist will look for abnormalities in the oral cavity and salivary glands. Depending on the suspected cause of dry mouth, further investigation may be necessary. These include determining the composition of saliva, the pH of saliva, and imaging scans of salivary glands.
Treatment of Dry Mouth
Dry mouth treatment depends on the actual cause. if it is a symptom of another disease, the treatment of this disease is necessary. The treatment of dry mouth may include:
- Drinking enough amount of water daily: dehydration occurs because of insufficient fluid intake or excessive fluid loss for example sweating, fever, diarrhea, or vomiting.
- Treat your sinusitis or allergy: if you have sinusitis, cold, or allergy that makes breathing through the nose difficult, you should visit your doctor for the treatment of this problem.
- Stress management: dry mouth can be a symptom of stress, anxiety, and depression. Relaxation technique and sports can reduce the stress level.
- Avoid smoking: the vasoconstrictor effect of smoking or chewing tobacco inhibits the circulation of your body, causing dry mouth.
- Change your medications: if you develop dry mouth as a side effect of some medications such as antihypertensive, antihistamines, sedative, and hypnotics, you should visit your physician to adjust the dose or change medications.
- Saliva substitutes: if dry mouth is caused by radiotherapy, chemotherapy, or Sjogren’s syndrome. Your doctor may prescribe saliva substitutes in the form of spray, gel, or lozenge to keep your oral cavity moist. Also, your dentist may prescribe some medications such as pilocarpine or cevimeline to stimulate the salivary glands to produce more saliva.
Note: Saliva substitutes is not a complete replacement for natural saliva. It doesn’t contain the digestive and antibacterial enzymes but it can relieve the discomfort of dry mouth.
Prevention of Dry Mouth
Dry mouth can cause serious consequences such as difficulty eating or swallowing, bad breath, fungal infections, mouth sores, frequent dental caries, and gum disease. To increase the production of saliva and prevent dry mouth, you should:
- Drink plenty of water: dry mouth occurs frequently due to dehydration especially in elderly people.
- Chew sugar-free gum: to stimulate the production of saliva.
- Nose breathing: breath through your nose rather than your mouth. Also, stop snoring by losing weight, avoid alcohol and smoking, and establish regular sleep patterns.
- Use a humidifier: to moisturize the air.
- Avoid alcohol, caffeine, and tobacco.
- Manage stress: sports and yoga can help you to handle stressful situations.
- Avoid sugary or acidic foods and drinks: if you have dry mouth condition, you should avoid sugary or acidic foods and drinks to prevent dental caries.
- Avoid salty and spicy foods: if you have dry mouth condition, you should avoid salty and spicy foods because they can cause mouth irritation.
- Maintain a good oral hygiene: brush and floss your teeth daily to prevent the consequences of dry mouth.
- Change your medications: consult your doctor or dentist if you develop dry mouth as a side effect of some medications. Your doctor may change the medication or the dosage.
- Use saliva substitutes and stimulants: in serious cases, the dentist may prescribe some medications to stimulate the production of saliva and saliva substitutes to keep the oral cavity moist.
- Visit your dentist regularly: visit your dentist at least once every 6 months to examine your oral cavity and prevent any dental problems.