This thesis seeks to be a review of current literature on oral manifestations of various gastrointestinal diseases. Each section details results from a different current piece of literature on the subject. The issue is that the focus of gastrointestinal diseases is usually not on extra-intestinal and oral issues. Oral problems could be the first sign with which a patient with inflammatory bowel disease presents. This is an exploration of various oral issues associated with H. pylori, GERD, and inflammatory bowel diseases. We will look at mainly presentation, and to a lesser extent, treatment of oral manifestations of gastrointestinal diseases. Doing so will allow us to recognize and be aware of the different oral manifestations of gastrointestinal diseases, leading to potentially earlier diagnoses.