Gastric juice entering the mouth causes dental erosion. Common causes for the migration of gastric juice through the lower and upper oesophageal sphincters are reflux disease, eating disorders, chronic alcoholism and pregnancy. Gastro-oesophageal reflux is a common condition affecting up to 65% of the western population at some point in their lifetime. A typical clinical sign of acidic gastric juice entering the mouth is palatal dental erosion. As the condition becomes more chronic it becomes more widespread. There have been relatively few randomised studies investigating the aetiology of acids causing erosion. Of the few that have reported their findings, it appears that gastric acids are equally likely to induce moderate-to- severe erosion as in dietary acids. This literature review reports the conditions associated with the movement of gastric juice and dental erosion using medical and dental sources.