Panoramic radiographs showing variations of the mental foramen (MF) position in the vertical plane in relation to premolars apex: classification by Fishel et al. .
A = the MF situated coronal to the apex; B = the MF situated at the apex; C = the MF situated apical to the apex.
Juodzbalys G, Wang HL, Sabalys G.
J Oral Maxillofac Res 2010 (Jan-Mar);1(1):e3. doi:10.5037/jomr.2010.1103