title: Maxillary first molar with an O-shaped root morphology: report of a case.
abstract: This case report is to present a maxillary first molar with one O-shaped root, which is an extended C-shaped canal system. Patient with chronic apical periodontitis in maxillary left first molar underwent replantation because of difficulty in negotiating all canals. Periapical radiographs and cone-beam computed tomography (CBCT) were taken. All roots were connected and fused to one root, and all canals seemed to be connected to form an O-shape. The apical 3 mm of the root were resected and retrograde filled with resin-modified glass ionomer. Intentional replantation as an alternative treatment could be considered in a maxillary first molar having an unusual O-shaped root.
authors.affiliation: Microscope Center, Department of Conservative Dentistry and Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Korea.
authors.forename: Yooseok
authors.initials: Y
authors.lastname: Shin
authors.forename: Yemi
authors.initials: Y
authors.lastname: Kim
authors.forename: Byoung-Duck
authors.initials: BD
authors.lastname: Roh
mesh_terms: D000328:Adult; D063405:Anatomic Variation; D001047:Apicoectomy / Q000379:methods; D054893:Cone-Beam Computed Tomography / Q000379:methods; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000473:pathology*; D005899:Glass Ionomer Cements / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008437:Maxilla; D008963:Molar / Q000000981:diagnostic imaging / Q000473:pathology*; D010485:Periapical Periodontitis / Q000628:therapy; D012184:Retrograde Obturation / Q000379:methods; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000379:methods*; D014090:Tooth Replantation / Q000379:methods
chemical_list: D005899:Glass Ionomer Cements; D012387:Root Canal Filling Materials