Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 10 1 2023 08 20 31 35 Fatemeh Abbasi Department of Oral Medicine, Hamadan University of Medical Sciences, Hamadan, Iran. Zeynab Bayat Department of Oral Medicine, Faculty Of Dentistery, Hamedan University of Medical Sciences, Hamedan Iran. Anita lahooti Dental Faculty, Student Research Committee, Hamedan University of Medical Sciences, Hamedan, Iran. 2023 01 15 2023 02 25 Dentigerous cysts are commonly seen in association with third molars and maxillary canines. Only  5–6% of dentigerous cysts are associated with supernumerary teeth. We report a rare case of dentigerous  cyst associated with an impacted anterior maxillary supernumerary tooth (mesiodens). A  30-year-old male reported to our Department of Oral Medicine, School of Dentistry at Hamedan  University of Medical Sciences, with chief complaint of a painless swelling in the anterior upper jaw  (in the region of incisors) for a duration of 3 month. At the time of his presentation, his medical  history was unremarkable, with no systemic problems and no report of pain. Although the association  of dentigerous cyst with an impacted supernumerary tooth (mesiodens) is rare, prevention  of harmful complications as developmental cyst, early diagnosis and treatment is necessary. The standard treatment is Enucleation.  Keywords: Dentigerous cysts; Mesiodens; Supernumerary teeth. https://jcr.tums.ac.ir/index.php/jcr/article/view/429 https://jcr.tums.ac.ir/index.php/jcr/article/download/429/374