Panoramic Radiographic Relationship of the Mandibular Foramen to the Anterior Border of the Ramus and Occlusal Plane as an Aid in Inferior Alveolar Nerve Block

The location of the mandibular foramen (MF) on digital panoramic radiographs can be an important guide for clinicians when administering the inferior alveolar nerve block (IANB) for dental anesthesia of the mandible. This study, aimed to assess the location of the MF relative to the anterior border (AB) of the ramus and the occlusal plane (OP) from digital panoramic radiographs. An observational case series study was conducted on digital panoramic radiographs from the oral and maxillofacial radiology department archives of patients at least 18 years of age with a 1:1 scale (100%). The samples had to have at least 2 lower molar teeth on both sides without any blurring, previous fracture of the ramus or other artifacts. The distance of the MF to the OP and the AB of the ramus was measured using a caliper. The role of age and gender were also analyzed statistically using the 2-way analysis of variance test. One hundred ninety-four digital panoramic radiographs were included in the analysis. The findings showed that the vertical distance of the MF to the OP was a maximum of 14.52 mm and a minimum of −3.0 mm (mean 4.32 ± 2.34 mm). The distance of the MF to the AB of the ramus was a maximum of 25.52 and a minimum 9.68 mm (mean 16.48 ± 3.28 mm). Based on these findings, the IANB target site for injection should be approximately 5 mm above the OP and approximately 16.5 mm beyond the AB of the ramus to achieve successful anesthesia of the mandible via standard IANB in an Iranian population.