Clinical Oral Investigations

, Volume 16, Issue 2, pp 387–393 | Cite as

Assessment of variations of the mandibular canal through cone beam computed tomography

  • Christiano de Oliveira-Santos
  • Paulo Henrique Couto Souza
  • Soraya de Azambuja Berti-Couto
  • Lien Stinkens
  • Kristin Moyaert
  • Izabel Regina Fischer Rubira-Bullen
  • Reinhilde Jacobs
Original Article


The neurovascular bundle may be vulnerable during surgical procedures involving the mandible, especially when anatomical variations are present. Increased demand of implant surgeries, wider availability of three-dimensional exams, and lack of clear definitions in the literature indicate that features of anatomical variations should be revisited. The objective of the study was to evaluate features of anatomical variations related to mandibular canal (MC), such as bifid canals, anterior loop of mental nerve, and corticalization of MC. Additionally, bone trabeculation at the submandibular gland fossa region (SGF) was assessed and related to visibility of MC. Cone beam computed tomography exams from 100 patients (200 hemimandibles) were analyzed and the following parameters were registered: diameter and corticalization of MC; trabeculation in SGF region; presence of bifid MC, position of bifurcations, diameter, and direction of bifid canals; and measurement of anterior loops by two methods. Corticalization of the MC was observed in 59% of hemimandibles. In 23%, MC could be identified despite absence of corticalization. Diameter of MC was between 2.1 and 4 mm for nearly three quarters of the sample. In 80% of the sample trabeculation at the SGF was either decreased or not visible, and such cases showed correlation with absence of MC corticalization. Bifid MC affected 19% of the patients, mostly associated with additional mental foramina. Clinically significant anterior loop (>2 mm of anterior extension) was observed in 22–28%, depending on the method. Our findings, together with previously reported limitations of conventional exams, draw attention to the unpredictability related to anatomical variations in neurovascularization, showing the contribution of individual assessment through different views of three-dimensional imaging prior to surgical procedures in the mandible.


Cone beam computed tomography Jaw bone neurovascularization Mandibular canal Bifid mandibular canal Anterior loop of mental nerve Anatomical variations 



Author COS was granted PDEE scholarship—doctorate program with part of studies developed abroad, from CAPES-Brazil (Brazilian Government Agency).

Conflicts of interest

The authors declare no conflicts of interest regarding the manuscript and publication of the manuscript and its potential implications.


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Christiano de Oliveira-Santos
    • 1
    • 2
    • 5
  • Paulo Henrique Couto Souza
    • 1
    • 3
  • Soraya de Azambuja Berti-Couto
    • 1
    • 4
  • Lien Stinkens
    • 1
  • Kristin Moyaert
    • 1
  • Izabel Regina Fischer Rubira-Bullen
    • 2
  • Reinhilde Jacobs
    • 1
  1. 1.Oral Imaging Center and Department of PeriodontologyKatholieke UniversiteitLeuvenBelgium
  2. 2.Bauru School of DentistryUniversity of São PauloSão PauloBrazil
  3. 3.School of DentistryPontifical Catholic University of ParanáCuritibaBrazil
  4. 4.School of DentistryPontifical Catholic University of Rio Grande do SulPorto AlegreBrazil
  5. 5.SalvadorBrazil

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