The Effect of the Maxillary Sinus Volume on the Morphology and Angulation of the Infraorbital Canal in Relation to Age and Gender

Although the infraorbital canal (IOC) and maxillary sinus (MS) have been well studied, understanding the effect of MS volume (MSV) on IOC morphology is critical in determining the safest surgical route for infraorbital depression and transmaxillary procedures. Objectives: We aimed to describe the IOC types, measure the MSV and IOC angles (IOCA) in all three planes, and analyse the relationship between them using three-dimensional (3D) cone beam computed tomography (CBCT) images. Methods: CBCT images of 280 patients were analysed to identify the IOC types and accessory IOC (IOCa), and to measure morphometric parameters. The relationship between them was examined using statistical analysis in relation to age, gender, and laterality. Results: The most common IOC type was Type I (59.6%), followed by Type II (21.8%), Type III (13.6%), and Type IV (5%). According to MSV, three types of MS were described, with 38.2, 34.6, and 27.2% having normal, hypoplastic, and hyperplastic MS, respectively. Also, hyperplastic MS was associated with the highest likelihood of Type III IOC. Furthermore, logistic regression model revealed that the MSV and IOCA3 had a positive significant effect on the IOC protrusion, whereas being female, increasing age and IOCA1 had a negative significant effect on MS pneumatization. The probability of having hyperplastic MS, Types II and III IOC, IOCa also decreased with increasing age. Conclusions: Using 3D technology, the results of this study provide a detailed classification of IOC and MS types, increasing the number of treatment options and reducing the risk of complications during surgery. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article.