• Xerostomia refers to excessive dryness of the mouth and oral cavity. It is usually caused by defective salivary secretion by salivary glands and is most commonly due to Sjogren Syndrome. Excessive dryness of the oral mucosa can ultimately lead to its fisuring and ulceration. Furthermore, because saliva is critical for preventing overgrowth of bacteria on teeth, xerostomia is associated with an increased incidence of dental carries.