Background: In the past when antibiotics were not used as widespread as today, many severe and fatal complications were occurred due to dental infections. Today, with the widespread use of these antibiotics, the rate of these complications decrease but may be seen although rare.
Case report: This article reports a case of a dental abscess that was complicated with mediastinitis, cervical cellulitis, left pneumothorax and bilateral thoracic empyema. The patient was successfully treated with bilateral tube thoracostomy and medical therapy. The unusual cause and the interesting clinical course of mediastinitis are described.
Conclusions: Descending necrotizing mediastinitis caused by odontogenic infections is distinct clinical entity that requires prompt diagnosis, rapid institution of broad-spectrum antibiotics, intense supportive care, and surgical drainage. Early recognition and aggressive treatment may be delay due to their relative low prevalence.

Keywords: mediastinitis, cervical cellulitis, thoracic empyema, Pneumothorax, odontogenic infections