The infraorbital canal (IOC) normally courses above the maxillary sinus in the orbit floor. During a retrospective study of cone beam computed tomography (CBCT) scans, we found a previously unknown variant of the IOC. The IOCs were absent, being replaced by lateroantral canals coursing around and not above the maxillary sinus to open at infraorbital foramina which were located above the second upper premolar teeth. On coronal multiplanar reconstructions, the lateroantral canals were located anatomically at the outer limit of the zygomatic recess of each maxillary sinus, while the upper wall of the sinus was devoid of any canal. Such rare variant should be kept in mind by dental practitioners and surgeons, as it can determine modifications of common procedures. In this regard, the anatomy of maxilla, as well as mandible, should be evaluated in CBCT on a case-by-case basis.
Apostolakis D, Brown JE (2013) The dimensions of the mandibular incisive canal and its spatial relationship to various anatomical landmarks of the mandible: a study using cone beam computed tomography. Int J Oral Maxillofac Implants 28(1):117–124. doi:10.11607/jomi.2372CrossRefPubMedGoogle Scholar
Hindy AM, Abdel-Raouf F (1993) A study of infraorbital foramen, canal and nerve in adult Egyptians. Egypt Dent J 39(4):573–580PubMedGoogle Scholar
Hwang SH, Kim SW, Park CS, Kim SW, Cho JH, Kang JM (2013) Morphometric analysis of the infraorbital groove, canal, and foramen on three-dimensional reconstruction of computed tomography scans. Surg Radiol Anat 35(7):565–571. doi:10.1007/s00276-013-1077-5CrossRefPubMedGoogle Scholar
Lawson W, Patel ZM, Lin FY (2008) The development and pathologic processes that influence maxillary sinus pneumatization. Anat Rec (Hoboken) 291(11):1554–1563. doi:10.1002/ar.20774CrossRefGoogle Scholar
Michalek P, Donaldson W, McAleavey F, Johnston P, Kiska R (2013) Ultrasound imaging of the infraorbital foramen and simulation of the ultrasound-guided infraorbital nerve block using a skull model. Surg Radiol Anat 35(4):319–322. doi:10.1007/s00276-012-1039-3CrossRefPubMedGoogle Scholar
Parnia F, Moslehifard E, Hafezeqoran A, Mahboub F, Mojaver-Kahnamoui H (2012) Characteristics of anatomical landmarks in the mandibular interforaminal region: a cone-beam computed tomography study. Med Oral Patol Oral Cir Bucal 17(3):e420–e425PubMedCentralCrossRefPubMedGoogle Scholar
Tubbs RS, Loukas M, May WR, Cohen-Gadol AA (2010) A variation of the infraorbital nerve: its potential clinical consequence especially in the treatment of trigeminal neuralgia: case report. Neurosurgery 67(3 Suppl Operative):onsE315. doi:10.1227/01.NEU.0000374675.19487.FA (discussion onsE315)PubMedGoogle Scholar