The Dental Hygienists must possess knowledge of preventive dentistry, general and oral anatomy, physiology, histology, nutrition, dental materials and instruments, dental hygiene techniques and principles to provide specialized prophylactic and preventive treatment to patients with advanced periodontal disease and other related dental problems. Knowledge of tooth morphology, oral anatomy, oral physiology, radiology, nutrition, the principles and techniques of preventive dentistry, the instruments and materials to perform procedures including prophylaxis, examinations of the oral cavity, taking and interpreting x-rays for presence of calculus, and providing oral health care instructions to patients and the health services staff.