Pneumomediastinum is defined as the presence of free air between mediastinal structures. Although most of the cases occur spontaneously or due to traumatic reasons, they may rarely be observed after dental procedures. It is considered that the use of high speed air turbin drill during dental procedures might cause mediastinal emphysema. High-pressured air dissects the soft tissues starting from the impaired dento-alveolar membrane and reaches the mediastinum. Contaminated fluid and air can reach the mediastinum after the deterioration of the intraoral barrier and may result in highly mortal descending mediastinitis. In this article, we present a 53-year-old female patient of pneumomediastinum developing after tooth extraction using high-speed air turbine.