Dental barotrauma is a condition in which barometric pressure changes in the external environment cause damage to the dentition. The problem can occur owing to a miniature void within a filledtooth. It is technically difficult to completely prevent void spaces occurring when placing a filling and carrying out root canal treatment. According to Boyle's law, when the external pressure rises or falls the trapped air within the void will attempt to expand or contract. The stresses this places on the tooth structure can cause pain, or rarely fracturing of the tooth structure. Typically this is seen in scubadivers or aviators who experience pressure changes in the course of their activity. Identifying the pain during a pressure change is a diagnostic indicator for the clinician. Treatment involves removing the void space by carefully replacing the offending restoration, repeating the endodontic treatment or removing the tooth.