This document discusses oral manifestations of systemic medical disorders. It categorizes and describes various diseases that can present with oral signs and symptoms, including infectious diseases like herpes, HIV, tuberculosis; connective tissue disorders like lupus and scleroderma; gastrointestinal conditions like celiac disease and liver disease; nutritional deficiencies; and endocrine disorders like diabetes and Addison's disease. Common oral locations of lesions are described for each condition. The document provides an overview of how systemic illness can impact the mouth.