title: Position and orientation of the maxillary first permanent molar and localized attachment loss.
abstract: OBJECTIVE
  To investigate associations between the position and orientation of the maxillary first permanent molar and localized attachment loss (localized gingival recession or alveolar bone concavity) at the mesiopalatal aspect of this tooth.
  
  
  METHODS
  The study samples were 30 orthodontic study casts of young patients treated without premolar extractions, 45 pretreatment adult periodontal patient study casts, and 56 adult skulls. Measurements made were the maxillary first permanent molar crown angulation, inclination, rotation, and arch position, as well as the presence or absence of localized gingival recession/alveolar bone concavity at the mesiopalatal aspect of the tooth.
  
  
  RESULTS
  Localized attachment loss was most frequent in the periodontal study casts. The localized attachment loss was significantly associated with crown angulation, inclination, and type of sample but not with crown rotation and arch position.
  
  
  CONCLUSIONS
  Orthodontists need to consider the final position of the maxillary first molar crown in terms of its angulation and inclination to reduce the likelihood of the localized attachment loss at the mesiopalatal aspect of the maxillary first molar.
authors.affiliation: Medical Research Council and University of the Witwatersrand Dental Research Institute, Johannesburg, South Africa. cleatonjonesp@dentistry.wits.ac.za
authors.forename: Alf
authors.initials: A
authors.lastname: Volchansky
authors.forename: Bill
authors.initials: B
authors.lastname: Evans
authors.forename: Peter
authors.initials: P
authors.lastname: Cleaton-Jones
mesh_terms: D000293:Adolescent; D000328:Adult; D016301:Alveolar Bone Loss / Q000145:classification*; D003724:Dental Arch / Q000473:pathology; D005889:Gingival Recession / Q000145:classification*; D006801:Humans; D008437:Maxilla / Q000473:pathology; D008963:Molar / Q000473:pathology*; D009811:Odontometry; D017622:Periodontal Attachment Loss / Q000145:classification; D012399:Rotation; D019228:Tooth Crown / Q000473:pathology