Anat Cell Biol.  2020 Dec;53(4):512-515. 10.5115/acb.20.153.

A rare case of trifid mandibular canal with bilateral retromolar foramina

• KMID: 2509699
• DOI: http://doi.org/10.5115/acb.20.153

Abstract

There are many reported anatomical variations of the mandibular canal. Consequently, there is great variation in the retromolar area, such as the quantity, size, and location of the retromolar foramen (RMF), the bony entrance of the retromolar canal (RMC). These variations allow for different accessory innervations to the mandibular molars and their adjacent buccal tissue because the RMC contains neurovascular bundles. Consideration of these anatomical variations is crucial for avoiding complications in anesthesia, implant placement, and surgery. However, the rarer canal types are often only imaged by computed tomography (CT) or cone beam computed tomography (CBCT). We present a rare case with bilateral RMF and a unilateral trifid mandibular canal in a cadaver.

Keyword

Mandible; Oral surgery; Anatomy; Anatomic variation; Cadaver

Figure

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  Fig. 1 A dry mandible demonstrating double retromolar foramina on the right (A, B) and a retromolar foramen on the left (C). The three retromolar foramina are labeled.

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  Fig. 2 Continuation of the retromolar foramen and superior canal on the left shown with a metal wire.

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  Fig. 3 A closer look at the retromolar foramina under the surgical microscope with ×5, ×10, ×20 magnified view documenting their diameter. Note the trifid mandibular canal is observed from a posterior view.

Reference

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