title: Conventional and surgical endodontic treatment of a maxillary first molar with unusual anatomy--a case report.
abstract: OBJECTIVE
  To describe conventional and surgical endodontic treatment of a maxillary left first molar with two canals on the distobuccal root and to discuss the treatment outcome.
  
  
  CONCLUSIONS
  According to the literature, the presence of a second canal on the distobuccal root of a maxillary first molar is rare. This anatomical anomaly might lead to an unfavourable outcome if clinicians fail to identify and treat it properly. The following case report describes conventional and surgical endodontic treatment of a maxillary left first molar with two canals on the distobuccal root. Key learning points • Anatomical variations of the root canal system are a challenge for clinicians during root canal retreatment. • The principles and techniques of endodontic microsurgery are of utmost importance in clinical practice, and clinicians should be aware of them.
authors.affiliation: Department of Endodontics, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, USA. sflo_@hotmail.com
authors.forename: S
authors.initials: S
authors.lastname: Floratos
authors.forename: S I
authors.initials: SI
authors.lastname: Kratchman
mesh_terms: D005260:Female; D006801:Humans; D008437:Maxilla; D008866:Microsurgery; D008875:Middle Aged; D008963:Molar / Q000033:anatomy & histology*; D010485:Periapical Periodontitis / Q000601:surgery*; D019233:Retreatment; D012184:Retrograde Obturation / Q000379:methods*; D012389:Root Canal Obturation / Q000379:methods*; D018915:Root Canal Preparation / Q000379:methods; D019553:Tooth, Nonvital / Q000628:therapy*