Diagnosing, managing, and preventing salivary gland disorders

Salivary function provides host protection, assists in the initiation of food and fluid intake, and enables communication through speech. Without adequate salivary output, oral and pharyngeal health declines along with a person's quality of life. The complaint of a dry mouth (xerostomia) and the objective finding of salivary dysfunction are common occurrences in older individuals, producing transient and permanent oral and systemic problems. Salivary dysfunction, however, is not a normal consequence of growing older, and is due to systemic diseases, medications, and head and neck radiotherapy. Diagnosis of salivary disorders begins with a careful medical history, head, and neck examination. While complaints of xerostomia may be indicative of a salivary gland disorder, salivary diseases can present without symptoms. Therefore, routine examination of salivary function must be part of any head, neck, and oral examination. Therapies are designed to prevent the development of oral and pharyngeal sequelae of salivary hypofunction. Current xerostomia-based treatments include replacement therapies and gustatory, masticatory, and pharmacological stimulants. Health-care professionals can play a vital role in identifying patients at risk for developing salivary dysfunction, and should provide appropriate preventative and interventive techniques that will help preserve a person's health, function, and quality of life. The prevalence of xerostomia and salivary gland disorders is difficult to ascertain because of methodological differences in study populations and diagnostic criteria. The majority of patients treated for salivary disorders are those with Sjögren's syndrome (SS), adults being treated for head and neck cancer and those taking medications with antisialogogue sequelae. Combining these populations, the prevalence of xerostomia increases with age, and is probably ∼30% of the population aged 65+ years (Ship, Pillemer and Baum, 2002). Frequent oral symptoms of dry mouth are associated with mealtime. These complaints include altered taste; difficulty in eating, chewing, and swallowing, particularly dry foods; impaired eating without drinking accompanying liquids; and insufficient retention of or poorly fitting removable prostheses. Patients also complain of halitosis, a chronic burning sensation (stomatodynia) and intolerance to spicy foods that can affect the quality of a person's life (Fox et al, 1985; Mandel, 1989; Atkinson and Wu, 1994). These problems can lead to changes in food and fluid selection that may compromise nutritional status. They also can lead to choking, as well as an increased susceptibility to aspiration pneumonia, with consequent colonization of the lungs with gram-negative anaerobes from the gingival sulcus (Gibson and Barrett, 1992; Terpenning et al, 1993; Loesche et al, 1995). Xerostomia complaints at night-time are common, as salivary output normally reaches its lowest circadian levels during sleep (Dawes, 1975). These latter problems may be exacerbated by diminished oral motor tone leading to increased mouth breathing. Many older adults experience salivary gland dysfunction and complain of xerostomia (Locker, 1993; Narhi, 1994; Thomson et al, 1999). While it was previously thought that salivary function declined with greater age, it is now accepted that output from major salivary glands does not undergo clinically significant decrements in healthy individuals (Baum, 1981; Heft and Baum, 1984; Ship and Baum, 1990; Challacombe, Percival and Marsh, 1995; Ship, Nolan and Puckett, 1995; Vissink et al, 1996). Salivary constituents also appear to be age-stable in the absence of major medical problems and medications (Wu et al, 1993; Rayment et al, 2000). It is likely that numerous medical conditions and their treatments (medications, head and neck radiation, chemotherapy) contribute significantly to salivary gland dysfunction in the elderly (Mandel, 1980; Atkinson and Fox, 1992; Wu and Ship, 1993; Atkinson and Wu, 1994; Sreebny and Schwartz, 1997). Secretory reserve of salivary glands has been postulated to become diminished with increased age (Scott, Flower and Burns, 1987; Baum, Ship and Wu, 1992; Patel, Ghezzi and Ship, 2001), which may account for the greater prevalence of salivary disorders in the elderly, especially those taking medications. Further, biting forces have been correlated with salivary flow rates, and as biting forces may diminish with age, these may also play a role in the prevalence of xerostomia in the elderly (Yeh et al, 2000). The extra and intraoral examination of the patient with salivary dysfunction will yield numerous hard and soft tissue signs. Extraoral findings include dry and cracked lips that are frequently colonized with Candida species (angular cheilitis). Visible enlargement of the major salivary glands may occur in patients with viral infections (mumps), salivary obstructions (secondary to salivary hypofunction), and SS. Some older adults develop an acute parotitis after undergoing extended periods of dehydration and general anesthesia. A swollen parotid gland can displace the earlobe and extend inferiorly over the angle of the mandible. Medial to the posterior-inferior border of the mandible, a submandibular salivary gland swelling can be palpated. The glands may or may not be tender, and swelling is often recurrent (distinguishing it from mumps). Intraoral findings of salivary gland dysfunction may range from subtle to obvious. The tongue becomes furrowed, desiccated, and sticky. Dry oral mucosal tissues become susceptible to trauma; oral mucositis leads to pain and increased likelihood of developing microbial infections. Palpation of the parotid papilla (at Stenson's duct) reveals little or no salivary output, whereas in the presence of a parotitis, palpation will yield suppurative material. Examination of the floor of the mouth (at Wharton's duct) often reveals decreased or absent saliva pooling. Oropharyngeal swallowing difficulties are best evaluated by ultrasound studies. Food bolus formation and translocation can be perturbed in patients with reduced salivary output. One of the most common infections in patients with salivary dysfunction is oral candidiasis (e.g. Cannon and Chaffin, 1999). This fungal infection manifests itself as angular cheilitis of the lips, erythematous candidiasis beneath prostheses, and pseudomembraneous candidiasis as a white plaque that can be removed from all oral mucosal surfaces. A second frequent infection is new and recurrent dental caries. Recurrent carious lesions are particularly common among today's elderly, because of the high prevalence of retained natural teeth and previously restored dental surfaces (Shay, 1997). Edentulous and partially edentulous adults using removable prosthetic devices have diminished denture retention, which will impact adversely chewing, swallowing, speech, and nutritional intake (Ettinger, 1997). Denture-supporting mucosal tissues become friable and susceptible to traumatic lesions, further impairing use of removable prostheses. Speech and eating difficulties can impair social interactions and may cause some patients to avoid social engagements. Several scientifically validated questionnaires (Table 1) have been designed specifically for assessing salivary disorders and xerostomia, and may be helpful in clinical practice (Fox, Busch and Baum, 1987; Pai, Ghezzi and Ship, 2001). The majority of questions relate to xerostomia experienced during mealtime, and therefore these items may be most useful. Salivary hypofunction has also been predicted by four additional measures: dryness of lips, dryness of buccal mucosa, absence of saliva produced by gland palpation, and total decayed-missing-filled-teeth (DMFT) (Navazesh, Christensen and Brightman, 1992). Numerous investigators have attempted to define the lower limits of `normal' salivary flow rates. However, there is substantial variability in flow rates that makes it difficult to define diagnostically useful ranges of glandular fluid production. In studies of healthy persons across the lifespan, resting (unstimulated) fluid secretion varies 10–100-fold, while stimulated secretion varies 10–20-fold (Baum, 1981; Heft and Baum, 1984; Ship, Fox and Baum, 1991). Unstimulated secretions are probably more indicative of dry mouth complaints compared with stimulated secretions (Wang et al, 1998). Recent research data suggest that values below 45% of normal levels could be used to define salivary hypofunction (Ghezzi, Lange and Ship, 2000). It is also generally accepted that when an individual's glandular fluid production is decreased by about 50%, a person will begin to experience symptoms of oral dryness (Dawes, 1987). The best strategy is to simply monitor a patient's salivary health (both objectively and subjectively) over time (Ship et al, 1991). The composition of saliva also exhibits considerable variability (Rudney, 1995). While salivary exocrine proteins are critical for oral physiological performance, there are no common disease situations resulting in the deficiency of any single major salivary protein. Therefore, there is no practical reason to monitor the protein composition of a patient's saliva. Intraoral and extraoral salivary gland swellings should be evaluated using histopathological and imaging techniques, depending upon the clinical scenario. Minor salivary gland mucoceles can undergo excisional biopsies, whereas larger tumors will benefit from incisional biopsies for histopathologic diagnosis and tumor staging in order to plan subsequent therapies (Golden and Hooley, 1994). Sialograms can identify changes in the salivary gland architecture, and are useful for major salivary gland swellings (Stiller et al, 1999). They are performed with radio-opaque iodine and extraoral radiographs (lateral cephalograms, panographs). Radioactive isotype scintiscans (e.g. T99 pertechnetate) can provide a qualitative functional assessment of the major salivary glands (Kohn et al, 1992; Saito et al, 1997; Malpani, Jaiswar and Samuel, 1999). Magnetic resonance imaging and computerized tomography (CT) scans will help rule out salivary gland tumors and other pathoses associated with the craniofacial region that may adversely affect salivation. All salivary gland infections should be cultured to identify organisms that may be resistant to commonly used antibiotics. There are three classifications of intraoral sources of salivary gland diseases (infectious, non-infectious and neoplastic; Table 2) that must be considered in the diagnostic process of examining a patient with salivary dysfunction (Norman and Mitchell, 1998). Bacterial infections are more common in older persons who experience salivary hypofunction secondary to medications, head and neck radiation, systemic diseases, or dehydration (Almstahl and Wikstrom, 1999; Almstahl et al, 1999). Acute parotitis was commonly seen before the antibiotic era in terminally ill and dehydrated patients and contributed to mortality by sepsis. Now, acute parotitis is observed infrequently. Chronic parotitis is not unusual, and it follows obstruction of a major salivary gland duct with subsequent bacterial colonization and infection. Signs and symptoms of bacterial salivary infections include swelling, purulence from the major salivary gland duct, and pain (August et al, 1996). Viral infections occur in persons of all ages, particularly in immunocompromised patients, and parotid is by and as parotid gland swellings in infections to be with and are observed in of salivary diseases are most common because of obstruction of a salivary gland duct, and can be acute and chronic Acute from an or obstruction whereas chronic recurrent as a of infection and 2000). are the most common of the lower and are by a salivary gland duct is the resulting in a in the of the and submandibular glands are to as They present as lesions to obstruction and or lesions of saliva through the tissues of the floor of the mouth and the et al, 2000). Salivary gland swellings are also by which are of and resulting from dehydration and glandular They most frequently develop in the submandibular duct can be using palpation techniques in the floor of the mouth submandibular and and parotid Salivary gland tumors are the of a in and will be salivary gland tumors are The of salivary gland the parotid with the majority being salivary gland tumor increases with age, and these tumors are more common in the submandibular and in the submandibular or are and 1989; and 1997). to be and most commonly present as an in the of the parotid They are well and is the most common salivary gland by et al, and in a The most frequently intraoral is the by the Signs and symptoms of a salivary gland tumor include a swelling with or Several medical conditions are associated with salivary dysfunction (Table the most common being which will be in considerable in a in is a disease of may be as as out of with a during the or of life et al, Fox, and Pillemer et al, 2001). This is a systemic associated with of particularly exocrine glands et al, and is as or secondary SS. salivary and gland disorders with associated decreased production of saliva and In secondary the with other diseases, as systemic and et al, 1992). oral findings in the patient with xerostomia are as for other major salivary glands are common, because of salivary and However, it is to rule out in the presence of and significantly salivary glands and neck there is a in the of among patients et al, and commonly these are of associated tissues et al, 1997; et al, 1999). imaging (e.g. and and flow are helpful for a these are or of the swollen gland must be and symptoms of can be from a clinical examination. production in and in the are and disorders of the and The most commonly used diagnostic are the et al, which at four of to be (Table The of are oral and symptoms and of a salivary gland and the presence of will frequently be for or with the presence of et al, 1999). are present in of conditions associated with have salivary dysfunction, and et al, 1992; and 1998). individuals and those with syndrome frequently experience salivary dysfunction from of the glands and as a sequelae of medications et al, 2000). may cause changes in salivary secretions et al, 2001), and have been and salivary dysfunction et al, 1998). and will salivary a common and among the elderly, also has been associated with salivary hypofunction (Ship and 1997). The most common of medications salivary dysfunction have in of to the et al, that to or that may also adversely affect the quality and of salivary output. These medications include and and and and 1989; et al, 1995; et al, 1994; and 1995; Loesche et al, 1995; et al, 1997; et al, 1997; Sreebny and Schwartz, 1997; and 2000). Therefore, patients taking or more with antisialogogue sequelae should be for developing and symptoms of salivary for cancer has been associated with salivary disorders et al, 1995; et al, et al, 1998). These changes appear to occur during and after patients experience of salivary function to changes have been et al, Radioactive iodine used in the for of the gland has also been to cause parotid not submandibular dysfunction in a et al, is a common of for head and neck and neck has and to the oral the of salivary gland function and a complaint of a dry mouth et al, 1993; and et al, 1999). In patients often experience the of problems as a of permanent salivary gland et al, 1994; and 1996). All cancer patients should be for developing salivary disorders and their oral sequelae. The of salivary gland function will be the of a subsequent in for salivary dysfunction begins with appropriate a diagnosis has been is designed upon the of the and the the is salivary dysfunction, or can some symptoms of dry mouth the for of normal is as with head and neck for oral use of salivary and may Frequent dental are critical with a the of oral disorders that develop because of salivary and for patients oral and Wu, 1994; Fox, 1997). particularly older must be to is the of to with Several as mouth and of have been to the risk of or these should the of dry mouth symptoms 1994). and can salivary secretions (Table and 1992; and as well as secretion of salivary and 2001). In the absence of salivary saliva and may some symptoms. These to diminish the sensation of oral dryness and oral of and patients use and 1992). Several without a include and saliva saliva and et al, et al, et al, and et al, et al, 2001). xerostomia with medications that is (Table Atkinson and Baum, 2001), particularly in the healthy person for may not be a critical as can secretions and diminish complaints in patients with exocrine tissue (e.g. et al, 1993; et al, et al, 1999). is in a of three a and before before mealtime, patients may benefit from the increased in eating their The total should not include increased greater and and and Patients with a of chronic and angle should not A new has been by the Food and for the of dry mouth in in a of three 2000). it is a that increases production of saliva. is a whereas has a for and and are and can salivary secretions while and Patients with significant disease and angle should not has been used to saliva in head and neck patients, with significant et al, 1994). the there has been some in using techniques to et al, and 1997; and 2000). There are data that can an in stimulated saliva to after the of and 2000). is not commonly it a for patients who well to (e.g. have difficulty taking these medications because of secondary use and mouth help prevent in patients with reduced salivary flow (Table et al, et al, 1997; Fox, and 2000). are and of lesions, of lesions, and permanent of new and recurrent mouth can be used to prevent and et al, 1991). or are by or in soft or and and can prevent of in patients with salivary hypofunction. The secondary of salivary hypofunction soft tissues also appropriate diagnosis and oral mucosal tissues are more susceptible to and traumatic tissue mucosal to avoid et al, or systemic infections from oral Dry oral lesions are susceptible to developing secondary infections by microbial that normally the oral as well as by organisms et al, 1993; and for salivary infections (e.g. systemic with or and salivary Viral infections of salivary glands after in the systemic should be use of mouth (e.g. may also be candidiasis is the most frequent oral infection secondary to dry and is treated with (Shay, and 1997; and 1998). and are for most of oral candidiasis (Table and systemic (e.g. should be for disease and immunocompromised may fungal infections and Patients must be to of the and to the out of the mouth for extended periods and while can be for in or and A of oral or a of can be to the of a denture after cheilitis should be treated with a of and It is to that and and therefore the patient with salivary gland dysfunction at risk for dental should use of removable can become impaired and in the presence of oral tissues and the of adequate salivary output. oral of and mucosal tissues is as is for infections. and swallowing is with the of frequent of to avoid and problems can be diminished with frequent dental to identify and to with and and 1997). Dry eating and swallowing problems can intake of some adults to a soft and patients must be a adequate and the of intake, particularly with swallowing may be treated with oral and and careful use of during can provide some for patients significant oral Sjögren's syndrome of xerostomia, and its and (Fox et al, et al, 1993; et al, et al, 1998). and Fox, replacement of salivary gland tissue by salivary glands et al, 1999; et al, and the for et al, and Baum, are a and other as is to diminish the and of which is critical to the of permanent exocrine and and and are for patients with who have salivary gland These therapies are also for patients who have other systemic diseases associated with salivary dysfunction (e.g. of must be in with medical to avoid In the Sjögren's all fluid producing have been by salivary will not be These patients fluid with and of salivary dysfunction with the patient's The is to the of medications a person is taking that cause salivary hypofunction and Schwartz, 1997). the of is with medications with is Some of medications provide for a patient is taking an a could be to an have been to cause dry mouth and 1995; et al, 1998). is a new and a and was to provide with dry mouth symptoms compared with in a study for of major et al, 1997). A new for of and associated with disease is associated with complaints of dry mouth and 1999). and a of to of dry mouth et al, 1998). study that a of and produced dry mouth complaints and greater salivary flow rates compared with and 2001). Further, saliva output was at levels the with compared with lower salivary output in taking and those taking used to in et al, 2001). there are some that will provide with Salivary output is lowest during and before will a greater during these these medications can be during the patients can the and avoid at because of is to which will from a single In of the and of of medications can in the of and and neck significant and permanent salivary hypofunction and xerostomia, and therefore a of et al, 1994; and and 1999). for other problems should be in patients who have head and neck radiotherapy. are to in the salivary dysfunction that during radiotherapy. techniques, significant have been to parotid glands the of the resulting in salivary output, a of xerostomia, and of quality of life et al, 1999; et al, 2001). Further, it that the to the salivary glands does not impair with to tumors and considered to be at risk for cancer and that may not be reduced with these techniques et al, et al, during is the use of medications that may and provide and may provide and xerostomia associated with and et al, and 2000). can symptoms of xerostomia when during et al, and after the of et al, 1993; et al, 1993; and 1994; et al, 1995; et al, 1996). a et al, and a more may be useful for patients with salivary This will be in greater in a in a is with an appropriate diagnosis histopathological and imaging techniques and the most common salivary lesions, and of the of mucoceles is common, because of the of an salivary gland during and for salivary gland tumors varies significantly and is upon and of the as well as the and 1994). tumors careful as are and tissue after can the risk of tumor of and 1995). Recurrent lesions are frequently and is by the of the and of is in a and most often in tumors that have been present for at or tumors that have and numerous therapies 1993; and 1995). Recurrent salivary gland tumors more and radiotherapy. salivary tumors are at risk for tumor A of is used as an after et al, 1994). has been for salivary gland more and has not been to the of cancer is for pain in patients who have recurrent or tumors and 1997). of salivary gland disorders with for all This should palpation of all major salivary assessment of salivary output from Wharton's and Stenson's examination for the and symptoms associated with a dry and of the patient's medical and medications. those individuals at risk for developing salivary dysfunction (e.g. those taking must be patients about xerostomia should also be a of clinical examination (Table However, in the presence of salivary older persons are likely to complain of xerostomia, and therefore may be at increased risk of developing its sequelae and Ship, 1997; Ship and 1997; et al, 2001). communication all is critical for salivary dysfunction in