Saliva is one of the most complex but versatile and important body fluids and controls a number of systems which serve a wide spectrum of physiological needs. Similar to any fluid in the body even saliva can have eccentric variations, which either can be increase or decrease in levels that can be physiologic or pathologic disparities. Persistent alteration in the normal flow of saliva into the oral cavity is of considerable significance to the integrity of the oral tissues. Although not life threatening but result in overall reduction in the quality of life.Xerostomia is the subjective sensation of dryness of the oral mucous membrane with objective evidence of significantly decreased salivary flow. It is not a disease but an early symptom of several morbid systemic conditions with important implications for the medical and dental management of patients.Sialorrhea is a common problem in neurologically impaired children and in adults who have Parkinson's disease or have had a stroke. It is most commonly caused by poor oral and facial muscle control. It causes a range of physical and psychosocial complications, including perioral chapping, dehydration, odor, and social stigmatization.