Current therapies for xerostomia and salivary gland hypofunction associated with cancer therapies

Abstract

In cancer patients, as in the general population, medication is the most common cause of xerostomia. In general, saliva flow in these patients can be stimulated by mechanical or pharmacological stimulation of the salivary glands. Painful damaged oral mucosa can be treated by softening, lubricating mouthwashes or gels. A specific group of patients are those receiving radiotherapy for malignant tumours in the head and neck region. This treatment is inevitably associated with damages to the oral tissues, including the salivary glands, resulting in salivary gland hypofunction. When residual secretory capacity is present, it is advisable to stimulate the salivary glands by mechanical or gustatory stimuli regularly in these patients as supportive oral care. Alternatively, salivary flow can be stimulated by the use of cholinergic pharmaceutical preparations, such as pilocarpine or cevimeline. After the radiation therapy is ended, a dental check-up should be done every 3 months to allow control of any incipient oral inflammation and dental decay. For daily use, a special dentifrice (e.g. children's toothpaste) is recommended, since the taste of a regular dentifrice may be too strong for these patients. Nocturnal oral dryness can be alleviated by spraying the oral surfaces with water, or by applying a small amount of dentifrice on the dental smooth surfaces. When stimulation of salivary secretion fails, patients can be given palliative oral care in the form of application of mouthwashes and saliva substitutes. The daily use of a mouthwash, e.g. Biotène, Oral Balance or Zendium, or one of the saliva substitutes is indicated. Different types of saliva substitutes are now commercially available, containing different polymers as thickening agents, e.g. carboxymethylcellulose (Oralube and Glandosane), polyacrylic acid, and xanthan gum (Xialine). Recent developments, which are, however, still in the experimental stage, are bio-active saliva substitutes and mouthwashes containing antimicrobial peptides to protect the oral tissues against microbial colonization and to suppress and to cure mucosal and gingival inflammation.