title: Detection of the genial spinal canal in atrophic mandibles with a CBCT: a cadaver study.
abstract: OBJECTIVE
  The use of a single midline implant to retain a complete mandibular denture when more implants cannot be used is an incipient treatment modality. However, in the mandibular symphysis, the genial spinal canal (GSC) is an anatomical structure with neurovascular content that can be harmed during dental implant surgery. The purpose of the present study was to use CBCT of edentulous atrophic cadaver mandibles and evaluate how often the simulated placement of a single midline implant would contact the GSC if present.
  
  
  METHODS
  CBCT scans of 47 edentulous cadaver mandibles were performed. A digital simulation of the placement of a single midline implant (3.8 × 11.0 mm) was performed, and the implant-GSC contact was evaluated.
  
  
  RESULTS
  A GSC was detected in the CBCT scan of all atrophic mandibles. In 42 cases (89.4%), the single midline implant contacted the GSC. On average, the five cases without GSC contact had a higher alveolar ridge (4.1 mm) and a lower GSC (0.79 mm) than did the cases with GSC contact.
  
  
  CONCLUSIONS
  CBCT scans can adequately detect the GSC during pre-surgical diagnostics. There is a high risk of implant-GSC contact during surgery of the anterior mandible. However, the clinical relevance of such a contact is not known yet, because none of the clinical studies evaluating a single midline implant has reported any implant-GSC contact-related complications.
authors.affiliation: 1 Department of Oral-Maxillofacial-Surgery, University Hospital Schleswig-Holstein, Kiel, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Birkenfeld
authors.forename: M
authors.initials: M
authors.lastname: Becker
authors.forename: M
authors.initials: M
authors.lastname: Sasse
authors.forename: V
authors.initials: V
authors.lastname: Gassling
authors.forename: R
authors.initials: R
authors.lastname: Lucius
authors.forename: J
authors.initials: J
authors.lastname: Wiltfang
authors.forename: M
authors.initials: M
authors.lastname: Kern
mesh_terms: D000368:Aged; D001284:Atrophy; D002102:Cadaver; D054893:Cone-Beam Computed Tomography; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D005260:Female; D006801:Humans; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging*; D011300:Preoperative Care
chemical_list: D015921:Dental Implants
keywords: CBCT; atrophy; dental implant; genial spinal canal