Oral Radiology

, Volume 34, Issue 3, pp 189–198 | Cite as

Cone-beam computed tomography and anatomical observations of normal variants in the mandible: variant dentists should recognize

  • Taisuke KawaiEmail author
  • Iwao Sato
  • Rieko Asaumi
  • Takashi Yosue
Review Article


Many types of cone-beam computed tomography (CBCT) have recently been developed and are being used in many dental clinics. CBCT has significantly changed imaging diagnosis in dentistry by showing detailed structures in multiple dimensions with high spatial resolution. This allows dentists to confirm what cannot be recognized with conventional two-dimensional images, such as small neurovascular canals, the buccolingual location of structures/lesions, and the three-dimensional shapes of hard tissue structures. The aim of this study was to review the normal variants of detailed anatomical structures in relation with the mandibular canal by comparing the previous reports and anatomical evaluations. These structures are likely to be observed on CBCT images by dental practitioners prior to dental procedures involving the mandibular teeth and bone. Understanding the relationship of these structures is useful for dental practitioners and oral surgeons to reduce the possibility of causing damage and patient discomfort during dental procedures.


Mandible Mandibular canal Cone-beam computed tomography (CBCT) Anatomy Normal variant 



The authors received no funding for the preparation of this manuscript, but part of the results included in this review article were supported by a JSPS Grant-in-Aid for Young Scientists (B) (Grant Numbers JP20791376 and 24792013). The authors thank Dr. Yasuo Kumazawa (Professor Emeritus, Nippon Dental University) for his assistance.

Compliance with ethical standards

Conflict of interest

Taisuke Kawai, Iwao Sato, Rieko Asaumi, and Takashi Yosue declare that they have no conflict of interest.

Human rights statement and informed consent

Not applicable.


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Copyright information

© Japanese Society for Oral and Maxillofacial Radiology and Springer Japan KK, part of Springer Nature 2017

Authors and Affiliations

  1. 1.Department of Oral and Maxillofacial Radiology, School of Life Dentistry at TokyoNippon Dental UniversityTokyoJapan
  2. 2.Department of Anatomy 1, School of Life Dentistry at TokyoNippon Dental UniversityTokyoJapan

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