A study of greater palatine foramen and its importance in the application of maxillary nerve block in South Indian Population

Introduction: The greater palatine foramen (GPF) is located in the posterior part of the hard palate between the articulations of hard palate with the maxilla. GPF continues posteriorly and upwards as greater palatine canal (GPC) which opens in to the inferior wall of pterygopalatine fossa. Exiting the foramen rotendum, maxillary nerve enters the pterygopalatine fossa where it can be blocked. The intraoral route of GPF approach can be preferred for maxillary nerve block because of its low incidence of complications and high success rate. For achieving a painless intra operative period in procedures involving the maxillary region and for tooth extraction achieving a perfect maxillary nerve block is of at most importance. Our present study is aimed at correctly locating the position of GPF, its shape and patency in south Indian population which will be helpful for the intra oral approach of maxillary nerve block through the GPF Materials and Methods: The study was conducted in 30 dry adult skull bones of both sex. The molar relation, shape and the patency of the GPF were observed, the readings were obtained, statistically analyzed and compared with other studies. Results: In our observation on both side of skull, it was noted that GPF was located opposite to the 3rd molar in 90% of cases. Oval shaped GPF is most commonly found in our study which accounts to 53.35% and the overall patency rate for GPF was 95% in our study. Conclusion: Analysis and comparison of data has proven that the position, shape and patency of GPF may vary according to different races. This study has also confirmed that the maxillary nerve block via GPF is relatively safe and easier due to the consistency of the position, shape and the patency of the GPF in south Indian population. KEY WORDS: Greater palatine foramen, maxillary nerve block, regional blocks, Greater palatine canal, pterygopalatine fossa, Maxillary nerve.

Morphometric Analysis of Greater Palatine Canal via Cone-Beam Computed Tomography

SummaryBackground/Aim: The morphology of the greater palatine canal (GPC) should be determined preoperatively to prevent possible complications in surgical procedures required maxillary nerve block anesthesia and reduction of descending palatine artery bleeding. The purpose of this investigation was to evaluate the GPC morphology.Material and Methods: In this retrospective cross-sectional study, cone-beam computed tomography images obtained for various causes of 200 patients (females, 55%; males, 45%) age ranged between 18 and 86 (mean age±standard deviation=47±13.6) were examined. The mean length, mean angles of the GPC and anatomic routes of the GPC were evaluated.Results: The mean length of the GPC was found to be 31.07 mm and 32.01 mm in sagittal and coronal sections, respectively. The mean angle of the GPC was measured as 156.16° and 169.23° in sagittal and coronal sections. The mean angle of the GPC with horizontal plane was measured as 113.76° in the sagittal sections and 92.94° in the coronal sections. The mean GPC length was longer in males than in females.Conclusions: The results of this study showed that the most common pathway of the GPC was “first inferior, and then anterior-inferior direction” in sagittal plane and “first medial-inferior, then inferior direction” in coronal plane.

Infraorbital Foramen and Pterygopalatine Fossa Location in Dry Skulls: Anatomical Guidelines for Local Anesthesia

Purpose. The aim of the study was to locate the infraorbital foramen (IOF) in relation to the infraorbital margin (IOM) for proper injections of local anesthetics in skull specimens. Another aim was to determine the depth of needle penetration into pterygopalatine fossa through the greater palatine canal (GPC). Materials and Methods. 102 skull halves were used to measure the distances between (1) IOF and IOM and (2) IOF and alveolar ridge of maxilla at second premolar. Needles were inserted and bent at a 45° angle, passing through the GPC at the level of hard palate. The depth of the tip of needle emerging out of GPC into pterygopalatine fossa was measured. Results. The mean distance between IOF and IOM was 6.46±1.57 mm on the right side and 6.74±1.72 mm on the left. The mean distance between IOF and alveolar bone process of the maxilla at second premolar was 29.07±3.58 mm on the right side and 29.39±3.78 mm on the left. The mean depth of penetration of the needle into the pterygopalatine fossa was similar on both sides. Conclusions. Proper identification of IOF and pterygopalatine fossa is of great significance during local anesthesia injections, due to their close proximity to vital anatomic structures.