José Luis Llanos-Arteaga, Daniel Andrés Delgado-Piedra, Luis Alberto Llanos-Arteaga, Anderson Daniel Llanos-Arteaga, Juan Marcos Parise-Vasco
A dentigerous cyst associated with an ectopic third molar in the maxillary sinus is an extremely rare pathological entity that poses diagnostic and therapeutic challenges. We report the case of a 22-year-old woman with a four-month history of chronic nasal congestion and postnasal drip sensation, without a relevant medical history. Cone-beam computed tomography (CBCT) confirmed a cystic lesion associated with an ectopic third molar, allowing accurate three-dimensional assessment for surgical planning, with partial involvement of the left maxillary antrum. Given the size and location of the lesion, complete cystic capsule enucleation and ectopic tooth odontectomy were performed using the Caldwell-Luc approach under local anesthesia. Histopathological examination confirmed the diagnosis of a dentigerous cyst. Clinical and imaging follow-up at six months showed complete resolution of sinonasal symptoms and no evidence of recurrence. This case highlights that the Caldwell-Luc approach guided by CBCT remains a viable and effective option for treating extensive odontogenic cystic lesions involving the maxillary sinus.