Radio-Morphometric Evaluation of Greater Palatine Canal and Pterygopalatine Fossa Component: Maxillary Anesthetic Implications.

This is a retrospective analytical cross-sectional study involving 131 cone-beam computed tomography (CBCT) scans of adult (18-99 years) that assessed greater palatine canal (GPC) attributes (length, curvature angle, diameter of curvature) and the type of the trajectory of GPC-pterygopalatine fossa (PPF) component. The GPC is an important landmark that connects the oral cavity and PPF. It contains greater and lesser palatine nerves, along-with descending palatine artery and vein by extending from the inferior part of the PPF to the hard palate. The GPC acts as a pathway for infiltration of local anesthesia. The inferior orbital fissure (IOF) is in close proximity to these vital anatomic structures and hence accurate identification of its location during regional block anesthesia is crucial. This is one of the very few studies investigating these important structures on CBCT scans highlighting the importance of preoperative scans for the anatomic determination. The images were analyzed for the lengths and anatomic paths of the right and left GPC-PPF in sagittal plane. The diameters of the upper (higher bony aspect of PPF) and lower openings (GPC opening) displayed statistically significant differences in the comparison between males and females (P < 0.05). Overestimation or underestimation of the GPC length can cause a lack of anesthesia and undesirable diffusion of the anesthetic solution into the orbit thorough the IOF causing diplopia, or into the cranial cavity. A thorough understanding of GPC length and pathway types is obligatory for proper anesthetic administration and performing any maxillofacial procedures.