Salivary glands produce the saliva approximately 1 to 1.5 litres of saliva is produced per day.

Saliva is 90% water, but also contains protein used to: moisten the mouthinitiate digestion by break down starcheshelp protect the teeth from decay.

Obstruction

Obstruction to the flow of saliva most commonly occurs in the parotid and submandibular glands, usually because stones have formed.

Sialolithiasis is the formations of stones within the salivary gland or duct in which drains the salivary gland.

Salivary duct stone formations are the accumulation of calcium and phosphate crystals.

These stones can be present in any one of the glands including the parotid, the sublingual or the submandibular gland.

The parotid glands lie basically in front of the ears or just behind the jawline.

The submandibular and sublingual glands sit deep within the floor of the mouth.

Stones are much more likely to develop when the water content of saliva is decreased.

Thereby a person who is dehydrated is at much higher risk of stone formation.

Certain medications also predispose a person's likelihood of stone formation. These medications include antihistamines, antidepressants and diuretics.

Some disorders can cause thickening of the saliva and therefore increase a person's risk for stone formation.

Sjogren syndrome in a condition in which causes dryness of the mouth and other mucus membranes.

Some autoimmune conditions can also cause the body to attack its own salivary glands. These conditions can cause a decrease in saliva or thickening of the saliva and ultimately formation of stones.

Symptoms typically occur when eating. Saliva production starts to flow, but cannot exit the ductal system, leading to swelling of the involved gland and significant pain, sometimes with an infection.

Unless stones totally obstruct saliva flow, the major glands will swell during eating and then gradually subside after eating, only to enlarge again at the next meal.

Infection can develop in the pool of blocked saliva, leading to more severe pain and swelling in the glands.

If untreated for a long time, the glands may become abscessed. If a chronic bacterial infection gets into the gland, there may be scar formation in the area and the stone is likely to be more difficult to remove.

PreventionSalivary duct stones may be prevented by increasing the water content of one's saliva.

Some tips for increasing saliva water content is drinking six to eight glasses of water a day and massaging the salivary gland after eating in order to clear any thickened saliva.

Other methods include seeking treatment for any autoimmune disorder, sucking on sour hard candy and using prescription antihistamines.

Sialogogues is an agent or drug that increases the flow of saliva.

TreatmentsThe stone may be pushed or encouraged out of the duct if it is small enough by firm massage.

However for larger stones that cannot completely pass from the duct opening, a small incision may be made to remove it or the salivary duct

may be probed and thereby widening the opening of the duct .

Sometimes the gland and the stone may have to be completely excised.

Surgical removal of the stone however may cause scarring of the salivary duct opening. This can then interfere with the glands ability to properly drain. Other problems may happen then such as other stone formations along with infection. If the gland is removed, complications may include damage to one of the nearby facial nerves. This may then result in facial paralysis or loss of sensations in face or tongue.

Infection

The most common salivary gland infection in children is mumps, which involves the parotid glands.

While this is most common in children who have not been immunized, it can occur in adults.

However, if an adult has swelling in the area of the parotid gland only on one side, it is more likely due to an obstruction or a tumor.

A secondary infection of salivary glands from nearby lymph nodes. These lymph nodes are the structures in the upper neck that often become tender during a common sore throat.

In fact, many of these lymph nodes are actually located on, within, and deep in the substance of the parotid gland or near the submandibular glands.

When these lymph nodes enlarge through infection, A red, painful swelling in the area of the parotid or submandibular glands.

Lymph nodes also enlarge due to tumors and inflammation.

Salivary Gland Cyst (Sialocele, Mucocele, Oral Ranula and Cervical Ranula)

Salivary Gland Cysts occur as the result of trauma or obstruction to the Salivary Gland excretory duct and spillage of saliva into the surrounding soft tissue.

The blocked duct does not allow the saliva to exit into the mouth. The saliva, therefore, gets backed up in the gland and results in the enlargement and ballooning of the gland.

Salivary Gland Cysts can be classified as Sialocele, Mucocele, Oral Ranula, and Cervical Ranula.

Sialocele

Sialoceles are cysts of major Salivary Gland origin. Sialoceles are painless swellings of a major salivary gland.

Mucocele

Mucoceles are cysts of minor Salivary Gland origin. Mucoceles are painless, asymptomatic swellings that have a relatively rapid onset and fluctuate in size.

Oral Ranula

(a term derived from the Greek word for the swollen area below the mouth of a frog). Oral Ranulas are painless cysts that occur in the floor of the mouth and usually involve the major Salivary Glands. They do not extend beyond the mouth. Oral Ranulas usually present with swelling in the floor of the mouth that is painless. On occasion, they can interfere with speech or chewing.

Cervical Ranula

Cervical Ranulas (also known as Plunging Ranulas) are cysts that occur in the floor of the mouth and extend (plunge) into the neck. Cervical Ranulas usually present as a painless swelling in the neck.

Treatment

Occasionally, Salivary Cysts spontaneously resolve, especially in infants and young children. Although aspiration of Salivary Cysts does deflate them, this is temporary and almost all cysts return after aspiration. Small and asymptomatic Salivary Cysts can be observed.

Asymptomatic Sialoceles can be observed.

However if Sialoceles become symptomatic (obstruct salivary flow or get infected) or become cosmetically noticeable, surgical excision is recommended.

Surgical excision usually involves removal of the Salivary Gland that contains the Cyst.

If the Mucocele is small and superficial, it may respond to topical steroid treatment.

Larger Mucoceles require surgical removal for definitive treatment.

The preferred method of treatment of Oral Ranulas is complete excision of the Ranula and the associated sublingual gland.

Drainage, marsupialization and excision of the Ranula without the excision of the associated sublingual gland results in a high rate of recurrence of the Ranula.

The preferred method of treatment of Cervical Ranulas is the complete surgical excision of the oral portion of the Ranula with the associated sublingual Salivary Gland and drainage of the cervical cyst.

The most important factor in surgical management for Cervical Ranulas is removal of the responsible major Salivary Gland.

Tumors

Primary benign and malignant salivary gland tumors usually show up as painless enlargements of these glands.

Tumors rarely involve more than one gland and are detected as a growth in the parotid, submandibular area, on the palate, floor of mouth, cheeks, or lips.

These are most common in the parotid gland. 80% are benign tumors and typically present as a slowly growing salivary mass.

The risk of a salivary lump being malignant is higher for submandibular tumours (50% are malignant).

The most tumours occurring in the minor salivary glands are malignant but these are rare.

Factors suggesting that a salivary lesion may be malignant include:Rapid growthFixation of tumour to adjacent structuresFacial nerve involvement (invasion) resulting in facial muscle weaknessThe presence of enlarged neck lymph glands (although this may also be

found with inflammatory lesions).

Benign Parotid Tumours

The most common benign parotid tumour is a Pleomorphic Adenoma which is solid.

The second most common benign lesion is a Warthins Tumour which is cystic (Cyst-adenoma), and most commonly found in the inferior portion of the parotid. They present as a firm but mobile mass but they can become quite large if left untreated.

The majority (80-90% of parotid tumours) occur in the superficial aspect of the gland (superficial to the facial nerve) because 80-90% of the gland is superficial to the nerve.

In 10-20% of cases, however, tumours occur in the deep part of the gland, and such lesions can even present as a lump in the throat with expansion of an area called the parapharyngeal space at the back of the mouth. In this latter setting the lump may be visible by looking inside the mouth.

Benign salivary gland tumours only rarely cause facial weakness, a finding that is virtually diagnostic of malignancy, however pleomorphic adenomas have a risk of malignant change over a long period of time.

Malignant Parotid Tumours

The most common malignant tumour (70+%) of the parotid gland occurs as a result of involvement of the lymph glands present in the parotid by either a Squamous Cell Cancer (SCC) or melanoma (MM) of skin of the face or scalp.

These are highly aggressive tumours that often also spread to lymph nodes in the neck.

These tumours can involve the facial nerve causing facial weakness.

The mass feels hard and irregular and can be fixed to deep structures and/or invade the overlying skin causing discolouration or ulceration.

They may be palpable lymph nodes in the neck most frequently in the upper deep cervical region (level II) immediately below the parotid.

Submandibular Tumours

50% of these are malignant. The mass is below the jaw.

If malignant, they can invade adjacent structures and cause facial weakness and abnormalities in tongue function. If malignant, there again may be associated with enlarged lymph nodes.

Sublingual TumoursThe commonest tumour here is a mucous cyst called a Ranula. These may be confined to the floor of the mouth (simple Ranula), or they may extend down into the neck: a plunging or diving Ranula.

malignaancy of the sublingual gland are rare and usually present as a hard mass in the floor of the mouth and can often involve the lingual nerve causing numbness in the floor of the mouth and tongue.

Minor Salivary Gland Tumours

These are rare and virtually all are malignant.

They are most common in the palate.

The most common type is an adenoid cystic malignancy which has a tendency to invade along nerves and has a high incidence of local recurrence irrespective of the treatment employed.

Salivary gland enlargement also occurs in autoimmune diseases such as HIV and Sjögren's syndrome where the body's immune system attacks the salivary glands causing significant inflammation.

Dry mouth or dry eyes are common. This may occur with other systemic diseases such as rheumatoid arthritis.

Diabetes may cause enlargement of the salivary glands, especially the parotid glands.

Alcoholics may have salivary gland swelling, usually on both sides.

Sjögren's syndrome

Diagnosis of salivary gland disease depends on the careful taking of history, a physical examination, and laboratory tests.

Plain X-raySialographyUltrasoundCT and MRI scanning

Sometimes, a fine needle aspiration biopsy is helpful .

A lip biopsy of minor salivary glands may be needed to identify certain autoimmune diseases.

Treatment of salivary diseases falls into two categories: medical surgical.

Selection of treatment depends on the nature of the problem.

If it is due to systemic diseases (diseases that involve the whole body, not one isolated area), then the underlying problem must be treated.

If the disease process relates to salivary gland obstruction and subsequent infection, increased fluid intake and may prescribe antibiotics. Sometimes an instrument will be used to open blocked ducts.

If a mass has developed within the salivary gland, removal of the mass may be recommended.

Most masses in the parotid gland area are benign tumor.

When surgery is necessary, Parotidectomy is the removal of the parotid gland. The paratoid is usually removed because of a tumor, a chronic infection, or a blocked saliva gland, during surgery great care must be taken to avoid damage to the facial nerve within this gland that moves the muscles face including the mouth and eye

. When malignant masses are in the parotid gland, it may be possible to surgically remove them and preserve most of the facial nerve. Radiation treatment is often recommended after surgery. This is typically administered four to six weeks after the surgical procedure to allow adequate healing before irradiation.

Possible Complications Following Parotidectomy

a. Facial nerve injury.b. Sensory nerve injuryc. Bleedingd. Salivary leake. Facial sweating (Freys Syndrome)

Removal of a salivary gland does not produce a dry mouth, called xerostomia. However, radiation therapy to the mouth can cause the unpleasant symptoms associated with reduced salivary flow.

Medication or other conservative treatments that may reduce the dryness in these instances.