Mandibular nerve block at the oval foramen using reliable landmarks: refinement of a previously described procedure

The aim of this study was to improve the injection technique when blocking the mandibular nerve at the oval foramen by using consistent landmarks. The lower lateral orbital angle (LLOA) and the junction of the external acoustic canal and the mastoid process (AM) proved to be reliable landmarks. Distances between landmarks for the localization of the puncture point (PP), cranial indices as well as the angle of the injection needle to the sagittal plane were calculated on 22 human dried skulls. The PP was found to lie exactly in the middle between the LLOA and AM. The angle of the injection needle to the sagittal plane was 71.86 degrees. No correlation was found between the cranial index and the angulation of the needle or the distances for the localization of the PP. From this study a modified puncture technique was developed.