J Korean Assoc Oral Maxillofac Surg.  2017 Dec;43(6):395-400. 10.5125/jkaoms.2017.43.6.395.

Assessment of the anterior loop of the inferior alveolar nerve via cone-beam computed tomography

• Shaban B
• Khajavi A
• Khaki N
• Mohiti Y
• Mehri T
• Kermani H

• KMID: 2398994
• DOI: http://doi.org/10.5125/jkaoms.2017.43.6.395

Abstract

OBJECTIVES
The aim of this study was to evaluate different anatomical variants of the anterior loop of the inferior alveolar nerve (IAN) via cone-beam computed tomography (CBCT).
MATERIALS AND METHODS
CBCT images of 71 patients (36 males and 35 females) were evaluated. We used the classification described by Solar for IAN evaluation. In this classification, three different types of IAN loops were introduced prior to emerging from the mental foramen. We classified patients according to this system and introduced a new, fourth type.
RESULTS
Type I was seen in 15 sites (10.6%), type II in 39 sites (27.5%), and type III in 50 sites (35.2%). We found a new type in 38 sites (26.8%) that constituted a fourth type.
CONCLUSION
We found that type III was the most common variant. In the fourth type, the IAN was not detectable because the main nerve was adjacent to the cortical plate and the incisive branch was thinner than the main branch and alongside it. In this type, more care is needed for surgeries including inferior alveolar and mental nerve transposition.

Keyword

Anterior; Mental loop; Cone-beam computed tomography; Iran

MeSH Terms

Cerebral Cortex
Classification
Cone-Beam Computed Tomography*
Humans
Iran
Male
Mandibular Nerve*

Figure

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  Fig. 1 Both left and right mental foramina on the axial section and panoramic curve drawn on the axial section.

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  Fig. 2 A. Panoramic section showing type I on both sides; the guide plans for cross sections are also seen. B. Cross-sectional images showing type I.

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  Fig. 3 A. Panoramic view of type IV. B. Cross-sectional images of type IV.

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