Aim: 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. Conclusion: 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.
World J Orthod 2004;5:141–146.