Endoscopic and Intraoral Approach for Removal of an Ectopic Third Molar associated with a Dentigerous Cyst in the Maxillary Sinus: A Case Report

Dental ectopia is the presence of deciduous, permanent, or supernumerary teeth in non dentate areas. It is very rare, especially in the maxillary sinus. Treatment is surgical removal because left untreated, there is a tendency to form a cyst, tumour, or lesion that can cause the perforation of the orbital floor and the obstruction of the nasal cavity. Although, panoramic radiography is the common form of radiological examination for this type of eruption, Cone Beam Computed Tomography (CBCT) is the gold standard for pinpointing the exact location of the ectopic tooth and evaluating the characteristics of any associated lesion prior to a surgical procedure. A 17-year-old woman was referred with swelling, asymmetry, and local pain in her right maxillary region. On radiological examination, an ectopic third molar surrounded by a dentigerous cyst obstructing both the right maxillary and ethmoid sinuses was observed. The tooth was attached to the zygomatic bone, right under the orbital floor. Ectopic maxillary third molars are extracted mainly by the Caldwell-Luc technique but also by nasal endoscopy. The treatment of this eruption and its management is heterogeneous and multidisciplinary. In the present case, under general anaesthesia, the ectopic tooth and all cystic tissue occupying the entire right maxillary and ethmoid sinuses were successfully enucleated with an intranasal endoscopic approach by an otolaryngologist and with lateral sinus antrostomy, utilising a standard Caldwell-Luc approach, by an oral and maxillofacial surgeon. After the 6th and 12th months, the patient had no signs of sinus infection and had an uneventful recovery.