Imaging Sci Dent.  2015 Mar;45(1):61-65. 10.5624/isd.2015.45.1.61.

Accessory mental foramen: A rare anatomical variation detected by cone-beam computed tomography

• Torres MG
• de Faro Valverde L
• Vidal MT
• Crusoe-Rebello IM

• KMID: 2116793
• DOI: http://doi.org/10.5624/isd.2015.45.1.61

Abstract

The mental foramen is a bilateral opening in the vestibular portion of the mandible through which nerve endings, such as the mental nerve, emerge. In general, the mental foramen is located between the lower premolars. This region is a common area for the placement of dental implants. It is very important to identify anatomical variations in presurgical imaging exams since damage to neurovascular bundles may have a direct influence on treatment success. In the hemimandible, the mental foramen normally appears as a single structure, but there are some rare reports on the presence and number of anatomical variations; these variations may include accessory foramina. The present report describes the presence of accessory mental foramina in the right mandible, as detected by cone-beam computed tomography before dental implant placement.

Keyword

Anatomic Variation; Cone-Beam Computed Tomography; Mandible

MeSH Terms

Anatomic Variation
Bicuspid
Cone-Beam Computed Tomography*
Dental Implants
Mandible
Nerve Endings
Dental Implants

Figure

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  Fig. 1 Axial sections of the mandible show the presence of two mental foramina on the right side and one on the left. The foramina are located at the same level, and the accessory foramen (arrow) on the right side is located in the distal direction.

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  Fig. 2 Sequential parasagittal sections obtained every 1 mm in the distomesial direction on the right side of the mandible show the presence of two openings of the mandibular canal in the vestibular direction (two mental foramina) (arrows).

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  Fig. 3 Sequential coronal sections in the posteroanterior direction show two mental foramina on the right side and one on the left side, with their respective measurements in millimeters.

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  Fig. 4 Superior (A) and right lateral (B) view of three-dimensional cone-beam computed tomography reconstruction of the mandible show the presence of an accessory mental foramen on the right mandible.

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  Fig. 5 The accessory mental foramen is not detected on the panoramic radiograph.

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