Burning mouth syndrome is an idiopathic condition characterized by symptoms burning and / or pain of the oral mucosa with an orderly clinical finding. So far not found a unique way of treatment. It is a diagnosis that impairs the quality of life of patients, and consequently it can affect the quality of sleep. Melatonin is a hormone secreted from pineal gland and regulates the day-night rhythm of man, and whose production in the body decreases aging. The level of melatonin in saliva correlates well with the level of melatonin in plasma, therefore they are advantages of determining from saliva painlessness and non-invasiveness of the procedure itself. The purpose of this study was to compare the level of melatonin in saliva and the quality of sleep with help of the Epworth Sleepiness Scale in patients with burning mouth syndrome and control groups of patients without subjective oral disorders and with an orderly clinical finding.

Inclusion Criteria:

• female patients
• primary burning mouth syndrome
• without oral lesions

Exclusion Criteria:

• secondary burning mouth syndrome
• male gender
• patients with oral lesions

Female patients with burning mouth syndrome and age-matched female controls without burning mouth syndrome or oral lesions will be included in the study. A sample of unstimulated saliva will be taken from all patients and frozen. All patients will also fill in Epworth's sleepiness scale.