title: Anterior Loop of the Mandibular Canal-A Source of Possible Complications.
abstract: BACKGROUND
  Recognizing the radiographic position of the mental foramina is not sufficient to avoid complications during dental implant surgery. In many cases, the inferior alveolar nerve extends mesially as an "anterior loop" (AL). The aim of this study was to investigate the prevalence and spatial extension of the AL on computed tomography (CT).
  
  
  METHODS
  Thirty-seven human mandibles from an anatomical collection underwent CT analysis. Cross-sectional views and panoramic reconstructions were obtained. Prevalence and length of the AL were investigated.
  
  
  RESULTS
  Recognition of the AL on CT was 100%. Prevalence of the AL was 97.3% (n = 36). AL mean length was 2.26 mm (maximum: 7.0 mm).
  
  
  CONCLUSIONS
  Recognition of the AL on CT scans (100%) is higher compared with data in literature for detection on panoramic radiographs (38.2%). To avoid complications, it is important to detect the AL presence and its mesial extension from the mental foramen. Safety distance of at least 2 mm from the mesial extend of the AL is recommended. Therefore, 3D imaging techniques are advised for loops which courses are not clearly identifiable on panoramic radiographs.
authors.affiliation: *Senior Dentist, Department of Prosthodontics/Implantology, Eberhard Karls University, Tuebingen, Germany. †Resident, Department of Oral and Maxillofacial Surgery, Uniklinik RWTH Aachen, Aachen, Germany. ‡Dentist, Department of Prosthodontics/Implantology, Eberhard Karls University, Tuebingen, Germany. §Head of the Department, Division of Neuroradiology, Department of Radiology, Paracelsus Medical School, Salzburg, Austria.
authors.forename: Germán
authors.initials: G
authors.lastname: Gómez-Román
authors.forename: Nora Valerie
authors.initials: NV
authors.lastname: Lautner
authors.forename: Christoph
authors.initials: C
authors.lastname: Goldammer
authors.forename: Mark
authors.initials: M
authors.lastname: McCoy
mesh_terms: D003757:Dental Implantation / Q000379:methods; D006801:Humans; D008334:Mandible / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000601:surgery; D008340:Mandibular Nerve / Q000033:anatomy & histology; D011862:Radiography, Panoramic; D014057:Tomography, X-Ray Computed