From the Guidelines
Baseline evaluation of salivary gland function is recommended before starting treatment for oral dryness, and the therapeutic approach should be driven by the baseline measurement of salivary glandular function, rather than the patient's subjective feelings 1. To diagnose decreased salivary production, also known as hyposialia or xerostomia, several methods can be employed.
- The simplest approach is to measure unstimulated salivary flow by having the patient spit into a graduated container for 5-15 minutes, with normal production being 0.3-0.4 mL/min.
- Stimulated salivary flow can be tested by having the patient chew on paraffin wax or apply 2% citric acid to the tongue, then collecting saliva for 5 minutes, with normal production being 1-2 mL/min.
- Healthcare providers may also perform sialometry using specialized collection devices or conduct the Saxon test, where pre-weighed gauze is chewed for 2 minutes and then weighed again to measure saliva production. Additional diagnostic methods include:
- Salivary gland imaging (sialography, ultrasound, or MRI)
- Minor salivary gland biopsy
- Blood tests to check for underlying conditions like Sjögren's syndrome These tests are important because decreased salivary flow can lead to dry mouth, dental caries, oral infections, and difficulty speaking or swallowing. Common causes include medications (particularly antihistamines, antidepressants, and diuretics), radiation therapy, autoimmune disorders, dehydration, and aging. Non-pharmacological stimulation, such as using gustatory stimulants (sugar-free acidic candies, lozenges, xylitol) and/or mechanical stimulants (sugar-free chewing gum), is recommended as the first-line therapeutic approach for patients with mild glandular dysfunction 1. In patients with moderate glandular dysfunction, pharmacological stimulation with muscarinic agonists, such as pilocarpine or cevimeline, may be considered 1. It is essential to note that the therapeutic approach should be individualized based on the patient's specific condition and the severity of their symptoms. A multidisciplinary approach involving various health professionals is crucial in managing patients with decreased salivary production, particularly those with underlying conditions like Sjögren's syndrome 1.
From the Research
Diagnosis of Decreased Salivary Production
To diagnose decreased salivary production, also known as hyposialia (decreased saliva) or xerostomia (dry mouth), the following steps can be taken:
- A careful and detailed history and thorough oral examination are necessary for diagnosis 2
- Xerostomia is the subjective complaint of dry mouth or sensation of oral dryness, while hyposalivation is the actual decrease in measured salivary outflow 3
- Unstimulated whole salivary flow rate (UWS) can be measured to assess salivary flow rate 4
Assessment of Salivary Flow Rate
- Salivary flow rate can be assessed using methods such as measuring unstimulated whole salivary flow rate (UWS) 4
- Decreased salivary flow rate can cause xerostomia (symptoms of oral dryness) in patients who undergo hemodialysis (HD) 4
- Salivary flow rate can be increased using medications such as pilocarpine 4, 5
Treatment Options
- Treatment options for xerostomia and hyposalivation include salivary stimulants, topical agents, saliva substitutes, and systemic sialogogues 2
- Pilocarpine and bethanechol have been reported as potentially effective sialogogues for xerostomic patients 5
- Management of hyposalivation and xerostomia requires attention to the biology of saliva and the best means of providing a continuum of relief for people with xerostomia and hyposalivation 6