title: Posttraumatic Midface Pain: Clinical Significance of the Anterior Superior Alveolar Nerve and Canalis Sinuosus.
abstract: BACKGROUND
  Posttraumatic midface pain secondary to injury of the anterior superior alveolar nerve (ASAN) is characterized as pain localized to the central and lateral incisors, canines, and maxilla. This nerve is susceptible to injury and subsequent formation of neuromas after midface trauma. Surgical intervention requires an accurate and precise understanding of the course of the ASAN.
  
  
  METHODS
  Dissections of 12 human cadaver heads were conducted to identify the course of the ASAN through the canalis sinuosus (CS). Fifty 1-mm slice face computed tomographic scans were evaluated to document the dimensions and course of the CS.
  
  
  RESULTS
  The ASAN branched laterally from the infraorbital nerve before reaching the infraorbital rim in all cadavers. The bifurcation occurred 18 mm posterior to the infraorbital rim (range, 10-30 mm). At a point 25 mm inferior to the infraorbital rim, the ASAN is found 3.4 mm lateral to the piriform aperture (range, 3-4 mm). Radiographic analysis demonstrated a 12.9-mm horizontal length of the CS across the anterior maxilla (SD, 2.2 mm), a distance of 4.8 mm between the piriform aperture and the CS (SD, 1.2 mm), and 11.7 mm vertical length of the CS along the piriform aperture (SD, 3.0 mm).
  
  
  CONCLUSIONS
  The ASAN maintains consistent coordinates at specific points along its course through the midface. An improved understanding of the course of the ASAN will guide future diagnosis of injury to this nerve and surgical intervention for patients with posttraumatic midface pain secondary to ASAN injury.
authors.affiliation: From the Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Jonathon Bryce
authors.initials: JB
authors.lastname: Olenczak
authors.forename: Helen G
authors.initials: HG
authors.lastname: Hui-Chou
authors.forename: Demetrio J
authors.initials: DJ
authors.lastname: Aguila
authors.forename: Catherine Anne
authors.initials: CA
authors.lastname: Shaeffer
authors.forename: Arnold Lee
authors.initials: AL
authors.lastname: Dellon
authors.forename: Paul N
authors.initials: PN
authors.lastname: Manson
mesh_terms: D000328:Adult; D005157:Facial Pain / Q000209:etiology* / Q000601:surgery; D006801:Humans; D008442:Maxillary Nerve / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000293:injuries / Q000601:surgery; D014057:Tomography, X-Ray Computed; D061221:Trigeminal Nerve Injuries / Q000150:complications* / Q000601:surgery