Radiographic evaluation of the course and visibility of the mandibular canal

Purpose This study was performed to investigate the course of the mandibular canal on panoramic radiography and the visibility of this canal on both panoramic radiography and cone-beam computed tomography (CBCT). Materials and Methods The study consisted of panoramic radiographs and CBCT images from 262 patients. The course of the mandibular canal, as seen in panoramic radiographs, was classified into four types: linear, elliptical, spoon-shaped, and turning curves. The visibility of this canal from the first to the third molar region was evaluated by visually determining whether the mandibular canal was clearly visible, probably visible, or invisible. The visibihlity of the canal on panoramic radiographs was compared with that on CBCT images. Results Elliptical curves were most frequently observed along the course of the mandibular canal. The percentage of clearly visible mandibular canals was the highest among the spoon-shaped curves and the lowest among the linear curves. On panoramic radiographs, invisible mandibular canals were found in 22.7% of the examined sites in the first molar region, 11.8% in the second molar region, and 1.3% in the third molar region. On CBCT cross-sectional images, the mandibular canal was invisible in 8.2% of the examined sites in the first molar region, 5.7% in the second molar region, and 0.2% in the third molar region. Conclusion The visibility of this canal was lower in the first molar region than in the third molar region. The mandibular canal presented better visibility on CBCT images than on panoramic radiographs.

[1]  K. Reich,et al.  A histomorphometric analysis of the nature of the mandibular canal in the anterior molar region , 2013, Clinical Oral Investigations.

[2]  C Lindh,et al.  Visualisation of the mandibular canal by different radiographic techniques. , 1992, Clinical oral implants research.

[3]  P. Mentag,et al.  A review of the intraosseous course of the nerves of the mandible. , 1991, The Journal of oral implantology.

[4]  G. Townsend,et al.  Morphological variability of the human inferior alveolar nerve , 1997, Clinical anatomy.

[5]  K. Oikarinen,et al.  Comparison of three radiographic methods used to locate the mandibular canal in the buccolingual direction before bilateral sagittal split osteotomy. , 2002, Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics.

[6]  P. Heasman.  Variation in the position of the inferior dental canal and its significance to restorative dentistry. , 1988, Journal of dentistry.

[7]  O. Dilek,et al.  Assessment of the risk of perforation of the mandibular canal by implant drill using density and thickness parameters. , 2011, Gerodontology.

[8]  A. Katsumata,et al.  Relationship Between Cancellous Bone Density and Mandibular Canal Depiction , 2009, Implant dentistry.

[9]  R. Carter,et al.  The intramandibular course of the inferior alveolar nerve. , 1971, Journal of anatomy.

[10]  C Lindh,et al.  Measurements of distances related to the mandibular canal in radiographs. , 1995, Clinical oral implants research.

[11]  A. R. Vieira,et al.  Position and course of the mandibular canal in skulls. , 2012, Oral surgery, oral medicine, oral pathology and oral radiology.

[12]  Philip Worthington,et al.  Injury to the inferior alveolar nerve during implant placement: a formula for protection of the patient and clinician. , 2004, The International journal of oral & maxillofacial implants.

[13]  M. Paulin,et al.  Intrabony course of the inferior alveolar nerve in the edentulous mandible , 2004, Clinical anatomy.

[14]  R. Jacobs,et al.  Assessment of variations of the mandibular canal through cone beam computed tomography , 2011, Clinical Oral Investigations.

[15]  Gowgiel Jm.  The position and course of the mandibular canal. , 1992 .

[16]  A. Soler,et al.  Inferior alveolar nerve damage because of overextended endodontic material: a problem of sealer cement biocompatibility? , 2007, Journal of endodontics.

[17]  A Petersson,et al.  Location of the mandibular canal: comparison of macroscopic findings, conventional radiography, and computed tomography. , 1989, The International journal of oral & maxillofacial implants.

[18]  P. Monsour,et al.  Implant radiography and radiology. , 2008, Australian dental journal.

[19]  I. Rubira-Bullen,et al.  Visibility of the mandibular canal on CBCT cross-sectional images , 2011, Journal of applied oral science : revista FOB.

[20]  T. Muto,et al.  Computed tomographic analysis of the position and course of the mandibular canal: relevance to the sagittal split ramus osteotomy. , 2005, International journal of oral and maxillofacial surgery.

[21]  Christos Angelopoulos,et al.  Comparison between digital panoramic radiography and cone-beam computed tomography for the identification of the mandibular canal as part of presurgical dental implant assessment. , 2008, Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons.

[22]  M. Torabinejad,et al.  Anatomical relationship of the mandibular canal to its surrounding structures in mature mandibles. , 1992, Journal of endodontics.

[23]  A. Farman,et al.  Variations in the normal anatomy of the inferior dental (mandibular) canal: a retrospective study of panoramic radiographs from 3612 routine dental patients. , 1977, The British journal of oral surgery.

[24]  K. Gröndahl,et al.  Cone-beam CT for preoperative implant planning in the posterior mandible: visibility of anatomic landmarks. , 2009, Clinical implant dentistry and related research.

[25]  Anderson Lc,et al.  A review of the intraosseous course of the nerves of the mandible. , 1991 .

[26]  Hiroshi Watanabe,et al.  Visualization of the superior and inferior borders of the mandibular canal: a comparative study using digital panoramic radiographs and cross-sectional computed tomography images. , 2013, Oral surgery, oral medicine, oral pathology and oral radiology.

[27]  Z. Gu,et al.  Inferior alveolar canal course: a radiographic study. , 2009, Clinical oral implants research.