The salivary glands produce saliva to moisten the mouth, to help protect teeth from decay and to digest food.
You have three pairs of major salivary glands under and behind your jaw — parotid, sublingual and submandibular. Many other tiny salivary glands are in your lips, inside your cheeks, and throughout your mouth and throat. Salivary gland cancer most commonly occurs in the parotid gland, which is just in front of the ear. Treatment for salivary gland cancer often involves surgery. Viral infections such as mumps, flu, and others can cause swelling of the salivary glands. Swelling happens in parotid glands on both sides of the face, giving the appearance of chipmunk cheeks.. Salivary gland swelling is commonly associated with mumps, happening in about 30% to 40% of mumps infections. It usually begins approximately 48 hours after the start of other symptoms such as fever and headache. The most common cause of swollen salivary glands, salivary stones are buildups of crystallized saliva deposits. Sometimes salivary stones can block the flow of saliva. When saliva can't exit through the ducts, it backs up into the gland, causing pain and swelling. Salivary glands produce saliva, which moistens the mouth to help a person chew and swallow food. Saliva also contains substances (enzymes) that begin the breakdown of food. There are four pairs of salivary glands: 1  The parotid glands are located between the ear and the jaw. 1 The submandibular glands are located under the jaw. 2  The sublingual glands are located on the floor of the mouth under the tongue. 3  The buccal glands are not shown in this picture. 4  They are located in the mucous membrane lining the cheeks and mouth. 5  These glands produce only a small amount of saliva. You have three major salivary glands: the parotid, submandibular, and sublingual glands. They are responsible for producing saliva. The most common cause of salivary gland problems is blocked glands, which can cause painful symptoms. Sialolithiasis and sialadenitis are problems that can occur in the salivary glands. Sialolithiasis occurs when stones made of calcium form in the salivary glands. These stones can block the glands, which can partially or completely stop the flow of saliva. Besides these glands, there are many tiny glands called minor salivary glands located in your lips, inner cheek area (buccal mucosa), and extensively in other linings of your mouth and throat. Salivary glands produce the saliva used to moisten your mouth, initiate digestion, and help protect your teeth from decay. Obstruction: Obstruction to the flow of saliva most commonly occurs in the parotid and submandibular glands, usually because stones have formed. Symptoms typically occur when eating. We call the major salivary glands the parotid, submandibular, and sublingual glands. They all secrete saliva into your mouth, the parotid through tubes that drain saliva, called salivary ducts, near your upper teeth, submandibular under your tongue, and the sublingual through many ducts in the floor of your mouth. Obstruction: Obstruction to the flow of saliva most commonly occurs in the parotid and submandibular glands, usually because stones have formed. Symptoms typically occur when eating. Salivary gland cancer starts in one of the salivary glands. It’s not just a single disease. There are actually several different salivary glands found inside and near your mouth. Many types of cancer and benign (non-cancerous) tumors can develop in these glands. The 2 main types of salivary glands are the major salivary glands and minor salivary glands. There are 3 sets of major salivary glands on each side of the face: 1  The parotid glands, the largest salivary glands, are just in front of the ears. A salivary gland infection occurs when a bacterial or viral infection affects the salivary gland or duct. The infection can result from reduced saliva flow or the blockage or inflammation of a salivary duct. The condition is called sialadenitis. Your mouth is almost constantly flushed with saliva. 
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what are the salivary glands