OBJECTIVES To describe the clinical case of a patient with a supernumerary dental element located in the premaxilla (mesiodens) in palatal position and centripetal migration. Oral surgery was performed allowing the avulsion of the same with a vestibular approach. MATERIALS AND METHODS A 50-year-old patient presented to our observation complaining of pain in the area of the premaxilla affected by a swelling, which was accentuated by palpation at the corresponding nasal cavity floor. The physical examination shows a swelling, painful on palpation, against the left premaxilla in the absence of fistulas and painful palpation of the left nasal cavity. The OPT visualization shows a supernumerary element included, with attached osteolytic area, rotated 180 degrees and in centripetal migration towards the left nasal cavity and root canal treatment of 2.2. The CT scan of the upper jaw highlights the supernumerary element located in the premaxilla and the relative osteolytic area in which the radicular apex of 2.2 is opened; the involvement of the cortical floor of the left nasal cavity is also evident. The surgery procedure is performed, under local anesthesia, with vestibular and supracrestal access. The vestibular flap was preferred because: - the mesiodens, despite being in a palatal position with respect to the adjacent dental elements, migrated very cranially, remaining only the apical third in relation to the contiguous 2.1 and 2.2; - the osteolytic area having become much more vestibularly allowed a simpler osteotomy breach than a palatal access. A full-thickness trapezoidal incision was made with an internal bevel. After skeletonization of the premaxilla, a vestibular breach is made, with Lindhemann's burs, that allows access to the included element. The extraction of the supernumerary element is carried out only after odontotomy, with transverse separation of the coronal half from the radicular half. After adequate irrigation of the cavity with sterile physiological solution, we proceed to carry out the suture with detached points. Anatomical and clinical healing of tissues required root canal retreatment of 2.1 and 2.2. RESULTS AND CONCLUSIONS The development of mesiodens, that begins in 50% of cases before birth, is characterized by a defective morphology and mineralization with an increase in the organic part and a lower content of inorganic part. 90% of supernumerary teeth are located in the premaxilla region. The etiology of this dental anomaly is largely unknown and it is possible to identify a hereditary factor only in 31%; as far as the pathogenesis is concerned, the most accredited theory is that the formation of mesiodens starts from a hyperactivity of the dental lamina following traumatic, accidental or genetic alterations. CLINICAL SIGNIFICANCE The interest of this clinical case derives from the fact that the supernumerary element, that remained asymptomatic for many years, was diagnosed following an acute inflammatory process in a patient who was no longer adolescent, given that in most cases the diagnosis of a supernumerary tooth occurs at a young age. We do not know the anatomical situation prior to the inflammatory process; it is very probable that the bacteria that caused the inflammatory process arrived by endodontics from 2.2, with the secondary involvement of the supernumerary and 2.1.
