title: Under your nose: a rare finding during dissection provides insights into maxillary supernumerary teeth.
abstract: BACKGROUND
  A supernumerary tooth was found during anatomical dissection. The position of this tooth, still impacted in the maxilla, and the associated pathology make this a rare case.
  
  
  METHODS
  During dissection by dental students of the sagittally-sectioned head of a cadaver, a supernumerary tooth was identified in the mid-palatal area. Further dissection revealed a swelling with a thin bony covering related to the crown of the tooth. The maxilla was removed en bloc and radiographic examination, CT scanning, electron microscopy and histology were undertaken.
  
  
  RESULTS
  The tooth had a crenulated occlusal surface and a single root. It was 25 mm posterior to the root apex of the permanent upper central incisor. The swelling, confirmed by radiographs and CT imaging to be associated with the crown, occupied approximately one-third of the maxillary sinus. The 3D shape of the cystic lesion was visualized by a composite digital movie.
  
  
  CONCLUSIONS
  The crown form, position of the tooth and the associated dentigerous cyst suggested it was a palatally developing supernumerary premolar which had been displaced to the palatal midline by the expanding cyst. This rare case highlights the learning and teaching opportunities available during dissection, showing important variations in both development and clinical anatomy.
authors.affiliation: Centre for Orofacial Research and Learning, School of Dentistry, The University of Adelaide, South Australia.
authors.forename: C
authors.initials: C
authors.lastname: Redwood
authors.forename: G C
authors.initials: GC
authors.lastname: Townsend
authors.forename: M
authors.initials: M
authors.lastname: Ghabriel
authors.forename: A H
authors.initials: AH
authors.lastname: Brook
mesh_terms: D002102:Cadaver; D003803:Dentigerous Cyst; D004210:Dissection; D006801:Humans; D007180:Incisor / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008437:Maxilla; D008443:Maxillary Sinus / Q000000981:diagnostic imaging / Q000473:pathology; D035583:Rare Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D019228:Tooth Crown / Q000000981:diagnostic imaging / Q000473:pathology; D014092:Tooth Root / Q000000981:diagnostic imaging / Q000473:pathology; D014095:Tooth, Impacted / Q000000981:diagnostic imaging / Q000473:pathology*; D014096:Tooth, Supernumerary / Q000000981:diagnostic imaging / Q000473:pathology*
keywords: Anatomical dissection; dental education; dentigerous cyst; odontogenesis; supernumerary tooth