Saliva, a colorless, fluid liquid with a special consistency produced by the preauricular, submandibular and sublingual glands, is transported from the glands where it is produced to the oral cavity via ducts. The glands produce nearly 5 liters of saliva per day. The duct of the preauricular salivary gland is located near the upper first molar; the ducts of the other salivary glands open into the mouth under the tongue. If we classify:
Minor Salivary Glands (Glandulae Salivariae Minores)
Minor Salivary Glands are small secretory glands of the oral cavity. They are named according to their location.
- Gl. labiales (on the lips)
- Gl. buccales (on the cheeks)
- Gl. molares (parallel to Gl. buccales under the mucosa at the level of the molars)
- Gl. palatinae (on the palate),
- Gl. linguales (on the lateral and posterior surfaces of the tongue)
Major Salivary Glands (Glandulae Salivariae Majores)
Glandula sublingualis: A gland located on the diaphragm oris (mouth diaphragm) under the tongue, has many excretory ducts and is mostly mucous. Ductus subligualis major is the main excretory duct. In addition, it also discharges saliva into the mouth with approximately 40 Ductus subligualis minores.
Glandula submandibularis: A salivary gland located just below the mylohyoid muscle, mostly serous. It discharges secretion just under the tongue with the ductus submandibularis.
Glandula parotis: The subauricular salivary gland located on the outer side of the mandible ramusum. Ductus parotideus (Stenon's duct) runs around the anterior edge of the masseter muscle and opens next to the upper second molar.
Content of Saliva
The basic component of saliva, which has alkaline properties, is water. In addition, it contains other substances produced by the salivary glands and various components naturally found in the oral cavity. We can list the substances found in saliva as follows:
Water, albumin, Various enzymes (lipase, amylase, lactic dehydrogenase, beta-glucuronidase, esterase, peptidase, phosphatase, ribonuclease, peroxidase), Carbohydrase, lysozyme, mucins, cystatins,
Nerve growth factor, epidermal growth factor, gustin, fibronectin, histatin,
Immunoglobulin-A, -G and –M, serum proteins, Lactoferrin, creatinine, sialic acid, urea, uric acid, lipids,
Nitrogen, electrolytes, ammonia, bicarbonate, calcium, chlorine,
Fluoride, iodine, phosphates, potassium, sodium, sulfates, thiocyanate, magnesium, etc.
In addition to these, the following may be among the components not secreted by the salivary glands: Fungi, serum and blood cells, Food residues, bacteria and bacterial products, Bronchial secretions, cell residues, viruses, etc.
The beneficial effects of saliva on the mouth and teeth can be summarized as follows;
- Saliva cleans the teeth mechanically.
- Saliva protects the teeth from decay.
- Saliva protects the oral mucosa with the yeasts it contains.
Salivary Gland Diseases
Congestion
Congestion is mostly seen in the parotid and submandibular glands due to stone formation. Complaints are typically seen while eating. While eating, saliva formation accelerates, but cannot flow due to obstruction and sometimes causes severe pain and swelling accompanied by inflammation.
Swelling, Edema
If the stones have not caused complete obstruction, the glands swell while eating and gradually subside after a while, until the next meal. Microbes reproduce more easily in the accumulated saliva and cause more severe pain and swelling. If not treated in a sufficient time, they can form an abscess. In some people, the main ducts of the salivary glands may be abnormal. These ducts can create narrowing, reduce the flow of saliva, and cause inflammation and obstruction complaints.
Inflammation
The most common salivary gland inflammation is "mumps", which affects the parotid gland. Although it is most commonly seen in children, it can also be seen in adults. If an adult has a swelling in the parotid gland area, there is a greater chance that it is due to a blockage or a tumor. Inflammation due to narrowing of the duct and decreased salivary flow was mentioned earlier. Secondary inflammation of the salivary glands may also occur due to inflammation of the adjacent lymph nodes. These lymph nodes are tender lymph nodes in the upper part of the throat that appear after a sore throat. Some of these lymph nodes are actually located above, inside, and below the parotid gland or next to the submandibular gland. When the lymph nodes become inflamed, they become red and painfully swollen. Lymph nodes also enlarge due to tumors and edema.
Tumors
Primary tumors of the salivary glands usually present themselves initially with painless swelling. Tumors are rarely found in more than one gland and can be found in the front of the ear, inside the mouth, palate, floor of the mouth, cheeks and lips. These swellings should be evaluated by ear, nose, throat and head and neck surgeons.
Diagnosis
Diagnosis of salivary gland diseases is made with a careful history, physical examination and laboratory tests. If a stone obstruction in the major salivary glands is suspected, it may be necessary to anesthetize the mouth where the gland opens and widen the canal to see if the stone is expelled. Before such a procedure, the location of the calcified stone can be determined with an X-ray.
If a mass is detected in the salivary gland, it is useful to take an X-ray of the area with a computerized tomography. This tomography can help determine whether the mass really originates from the salivary gland or a neighboring lymph node.
In many cases, a fine needle aspiration biopsy, which can be performed in the examination room, is helpful. The accuracy of this test is between 80 and 90%. It is not recommended to examine a piece of the mass by incision in the skin in the examination room. Open biopsy should be performed in the operating room due to the possibility of damage to the facial nerve that runs along with the parotid gland.
Treatment
It is divided into two main parts: Medication and surgery. The choice of treatment method depends on the problem. If the problem originates from a disease related to the whole body, it should be treated. This may require consultation with doctors in other branches. If the disease is related to obstruction and inflammation, antibiotics are used. Sometimes, intervention in the ducts is necessary.
If a mass has formed in the salivary gland, it may need to be removed. Most masses in the parotid gland are benign. When surgery is necessary, great care must be taken with the facial nerve that passes through this gland. If there is a malignant tumor in the parotid gland, the mass can be removed without damaging the majority of the facial nerve. Radiation therapy is often recommended after surgery. This treatment typically begins four to six weeks after surgery, during which time the tissues are allowed to heal.
The same principles apply to the minor salivary glands in the mouth and throat. Benign diseases are best treated with surgery alone, while malignant tumors require both surgery and radiation therapy. If the mass is a cancer of a lymph node adjacent to the salivary gland, then of course the treatment method changes. This type of treatment method can again be most effectively managed by an ear, nose, throat, and head and neck surgeon. In summary, there are many causes of salivary gland diseases. These diseases are treated with both medication and surgery. Such treatments are performed by an ear, nose, throat, and head and neck surgeon who is experienced in this field.
