Anatomical study of the pterygopalatine fossa pertinent to the maxillary nerve block at the foramen rotundum

Abstract The anatomy of the pterygopalatine fossa pertinent to the technique of maxillary nerve block at the foramen rotundum was investigated and the ability of inexperienced surgeons to apply the required angles of the injection needle to the sagittal plane in a clinical environment. In 85 dried human skulls the volume, length, width and depth of 159 intact pterygopalatine fossae were measured. The frequency of reaching the sphenopalatine foramen using a 20 G spinal needle advanced from the frontozygomatic angle through the pterygomaxillary fissure was determined. 49 oral surgery postgraduates aligned the injection needle with angles of 60° and 80° to the sagittal plane of a volunteer's head. The dimensions of the pterygopalatine fossa were inconsistent; volume (0.1–1 cm3 ), width (1–9 mm) and depth (6–22 mm) showed the greatest variations. An enlarged sphenoidal process and a narrow pterygomaxillary fissure (