Radiographic Evaluation of Infraorbital Canal Protrusion into Maxillary Sinus Using Cone-Beam Computed Tomography

Abstract

Objectives The aim of this retrospective study was to evaluate the relation of the infraorbital canal course with the maxillary sinus using cone-beam computed tomography. Material and Methods A total of 1000 infraorbital canals (IOC) were examined from 500 cone-beam computed tomography scans. IOCs were classified into three types based on the degree of protrusion into the sinus. The presence of Haller cells and mucosal thickening in the sinus were evaluated. The length of bony septum from the canal to the sinus wall (D1), the distance at which protrusion begins posterior to the inferior orbital rim (D2), the vertical distance from the canal to the sinus roof (D3), and the vertical distance from the canal to the sinus floor (D4) were measured. Results The prevalence of IOC protrusion into the sinus was 8.8%. There was a significant difference in the prevalence of Haller cells between IOC types (P < 0.01). However, no significant correlation was found between IOC types and the presence of mucosal thickening (P > 0.05). There was no significant difference in the mean D1, D2, and D3 between the genders (P > 0.05). The mean D4 was significantly higher in males than in females (P < 0.05). Conclusions The protrusion of infraorbital canals into the sinus is a common variation that must be considered to prevent accidental injury. Our findings suggest that the risk of injury to the descending canals is very low during routine dentoalveolar procedures because the protruded canal is not close to the sinus floor.

Protrusion of the infraorbital canal into the maxillary sinus: A cross-sectional study in Cairo, Egypt

“…Recent studies have revealed that this finding was not as rare as previously thought, with a prevalence in the literature ranging from 8.8% to 15.7%. 4 5 6 7 10 13 …”

“…In the reporting of this retrospective cross-sectional study, the RECORD statement - a checklist extended from the STROBE reporting guidelines for observational studies - was followed. Assuming an 8.8% prevalence of protruded IOCs (a figure based on the findings of Kalabalik et al 7 ), a total of 123 sinuses were needed for a margin of error of 5% and a 95% confidence interval. Sample size was calculated using Epi Info statistical software (version 7; Centers for Disease Control and Prevention, Atlanta, GA, USA).…”

“…However, its aberrant suspension may predispose a person to iatrogenic complications due to nerve encroachment, such as hypoesthesia, paresthesia, and/or permanent soreness. 4 6 7 Therefore, a thorough radiological assessment of potential nerve protrusion is crucial before planning sinus surgery. 6 7 Computed tomography (CT) is widely utilized in sinonasal diagnostic procedures.…”

“… 4 6 7 Therefore, a thorough radiological assessment of potential nerve protrusion is crucial before planning sinus surgery. 6 7 Computed tomography (CT) is widely utilized in sinonasal diagnostic procedures. Nevertheless, cone-beam computed tomography (CBCT) is often preferred by dentists and maxillofacial surgeons for maxillofacial imaging, due to its adequate spatial resolution and interactive display combined with sparing the patient the high radiation doses associated with CT scans.…”

“…Nevertheless, cone-beam computed tomography (CBCT) is often preferred by dentists and maxillofacial surgeons for maxillofacial imaging, due to its adequate spatial resolution and interactive display combined with sparing the patient the high radiation doses associated with CT scans. 7 …”