title: Characteristic findings on panoramic radiography and cone-beam CT to predict paresthesia after extraction of impacted third molar.
abstract: The purpose of this study was to compare findings on the relationship between impacted molar roots and the mandibular canal in panoramic and three-dimensional cone-beam CT (CBCT) images to identify those that indicated risk of postoperative paresthesia. The relationship between impacted molars and the mandibular canal was first classified using panoramic images. Only patients in whom the molar roots were either in contact with or superimposed on the canal were evaluated using CBCT. Of 466 patients examined using both panoramic and CBCT images, 280 underwent surgical extraction of an impacted molar, and 15 of these (5%) reported postoperative paresthesia. The spatial relationship between the impacted third molar root and the mandibular canal was determined by examining para-sagittal sections (lingual, buccal, inter-radicular, inferior, and combinations) obtained from the canal to the molar root and establishing the proximity of the canal to the molar root (in contact with or without loss of the cortical border and separate). The results revealed that darkening of the roots with interruption of the mandibular canal on panoramic radiographs and the inter-radicular position of the canal in CBCT images were characteristic findings indicative of risk of postoperative paresthesia. These results suggest that careful surgical intervention is required in patients with the above characteristics.
authors.affiliation: Division of Radiology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry.
authors.forename: Nana
authors.initials: N
authors.lastname: Harada
authors.forename: Subash
authors.initials: S
authors.lastname: Beloor Vasudeva
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Matsuda
authors.forename: Kenji
authors.initials: K
authors.lastname: Seki
authors.forename: Rishabh
authors.initials: R
authors.lastname: Kapila
authors.forename: Noboru
authors.initials: N
authors.lastname: Ishikawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Okano
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Sano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging; D008875:Middle Aged; D010292:Paresthesia / Q000000981:diagnostic imaging* / Q000209:etiology; D011862:Radiography, Panoramic; D014081:Tooth Extraction / Q000009:adverse effects*; D014095:Tooth, Impacted / Q000000981:diagnostic imaging* / Q000601:surgery; D055815:Young Adult