Background: Emphysema is a rare complication of dental procedures. The highest incidence has been associated with the use of air turbine handpieces. If not recognized and treated promptly, this complication can lead to serious outcomes. Methods: We present a case of a 43-year-old man who developed deep cervicofacial and subcutaneous emphysema of the face, neck and chest along with the specific voice change due to nose blowing shortly after alveolectomy of the lower right third molar. Results: The patient was hospitalized, conservatively treated, monitored and treated with intravenous antibiotic therapy. After two weeks he made a full recovery. Conclusions: It is essential to recognize and adequately manage emphysema, and to inform patients postoperatively not to blow their nose after third molar alveolectomy to prevent this rare but potentially serious complication. To our knowledge, this is the first reported case of voice alteration caused by nasopharyngeal emphysema following third molar alveolectomy.