Oral health is known to be associated with general health. Much oral significance is closely related to systemic diseases. There are several categories of systemic patients for whom specific needs of dental care and counselling are needed. In some instances, so as to reach the optimal total health care, a combination of medical and dental care is necessary. Furthermore, poor oral hygiene itself is a risk factor for systemic diseases such as periodontal status which can increase the severity of heart disease and diabetes. Oral hygiene assessments are important so as to eliminate predisposing factors for oral complications such as nasopharynx cancer, immune-compromised disease, diabetes and valvular heart diseases in patients. Since early assessment can reduce both the incidence and severity of oral complications, some early appropriate interventions can be engaged according to the individual's treatment needs. It is necessary to carry out consistency in the treatment by including periodically follow up and appropriate counselling to the patients, so they may be able to take care of themselves up to the desired outcome. This book focuses on the oral health care for specific groups of the systemic patients i.e. diabetes, head and neck cancers, cardiovascular disease, and AIDS.