title: Failure of tooth eruption involving a mandibular primary first molar: a case report.
abstract: OBJECTIVE
  Primary failure of tooth eruption involving primary teeth is unusual. The purpose of this report was to describe uneruption of a single mandibular primary first molar and the treatment outcome following limited orthodontic care.
  
  
  METHODS
  A 5-year, 3-month-old boy was referred to the authors' clinic for treatment of an unerupted primary first molar, 3 months after fenestration by an oral surgeon. Orthodontic traction was performed on the affected molar in the authors' clinic. The affected mandibular primary first molar was fully erupted and in occlusion 16 months after the first fenestration.
  
  
  RESULTS
  The histopathological diagnosis of the overlying tissue was pericoronal myxofibrous hyperplasia (PMH) without any calcified obstacles.
  
  
  CONCLUSIONS
  Of the 26 primary tooth eruption failure cases treated in the authors' clinic between 1979 and 2003, the present case was the only example of a primary first molar.
authors.affiliation: Division of Pediatric Dentistry, Department of Oral Health Science, Course for Oral Life Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan. sachipro@dent.niigata-u.ac.jp
authors.forename: Sachiko
authors.initials: S
authors.lastname: Hayashi-Sakai
authors.forename: Yo
authors.initials: Y
authors.lastname: Taguchi
authors.forename: Tadashi
authors.initials: T
authors.lastname: Noda
mesh_terms: D002675:Child, Preschool; D005882:Gingival Diseases / Q000150:complications* / Q000473:pathology; D006801:Humans; D006965:Hyperplasia; D008297:Male; D008334:Mandible; D008963:Molar / Q000503:physiopathology; D014078:Tooth Eruption; D014087:Tooth Movement Techniques; D014094:Tooth, Deciduous / Q000503:physiopathology*; D014095:Tooth, Impacted / Q000628:therapy*