Ectopic Tooth in the Maxillary Sinus.

Odontogenesis occurs because of a multi-stage complicated interaction between the oral epithelium and the mesenchymal tissue under the epithelium. Abnormal tissue interactions during this process can lead to ectopic tooth development (1). Ectopic tooth outside the oral cavity is rarely reported in the literature (1, 2) Ectopic teeth can be asymptomatic or can form odontogenic cysts, cause degradation of the bone, and can be the source of focal infection (3, 4).