title: Characteristics of intrabony nerve canals in mandibular interforaminal region by using cone-beam computed tomography and a recommendation of safe zone for implant and bone harvesting.
abstract: BACKGROUND
  Cone-beam computed tomography can accurately show anatomic structure of intrabony nerve canals in mandibular interforaminal region.
  
  
  OBJECTIVE
  The aim was to evaluate the characteristics of intrabony nerve canals in mandibular interforaminal region by using cone-beam computed tomography (CBCT) and determine a safe zone for implant and bone harvesting.
  
  
  METHODS
  Hemimandibles (824) CBCT images were obtained. The length of the anterior loop (AL), the length and diameter of the mandibular incisive canal (MIC) and its spatial distance in various landmarks were measured.
  
  
  RESULTS
  The prevalence of the AL was 93.57%, and the MIC was 97.33%. The mean lengths of the anterior extension of the anterior loop (aAL), caudal extension of the anterior loop (cAL) and the MIC were 2.53 ± 1.27 mm, 6.04 ± 1.66 mm, 9.97 ± 5.15 mm, respectively. The MIC was closer to buccal border and inferior margin of mandible. The length of the AL and diameter of the MIC varied with gender.
  
  
  CONCLUSIONS
  The safe zone recommended for implant surgery is 4 mm anterior and 8 mm inferior to the mental foramen, and 10 mm above the inferior margin of mandible. The chin bone should be harvested at least 10 mm below the tooth apices along with a limited depth of 4 mm.
authors.affiliation: Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China.
authors.forename: Xiang-Wen
authors.identifier: http://orcid.org/0000-0002-6024-0642
authors.initials: XW
authors.lastname: Yang
authors.affiliation: Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China.
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Zhang
authors.affiliation: Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China.
authors.forename: Yi-Han
authors.initials: YH
authors.lastname: Li
authors.affiliation: Stomatology Special Consultation Clinic, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wei
authors.affiliation: Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Gong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016025:Bone Transplantation; D002648:Child; D054893:Cone-Beam Computed Tomography; D015921:Dental Implants; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000601:surgery; D008340:Mandibular Nerve / Q000033:anatomy & histology*; D008875:Middle Aged; D020858:Tissue and Organ Harvesting / Q000379:methods*
chemical_list: D015921:Dental Implants
keywords: anterior loop; bone grafting; cone beam computed tomography; implant; mandibular incisive canal; nerve injury