Landmarks | Porion (Po) | Highest point on roof of external auditory meatus |
Orbitale (Or) | Deepest point on infraorbital margin |
Nasion (Na) | Most posterior point on curvature between frontal bone and nasal bone in midsagittal plane |
Opisthion (Op) | Most posterior point on posterior margin of foramen magnum |
Cdsup | Most superior point of condyle |
Cdlat | Most lateral point of condyle |
Cdpost | Most posterior point of condyle |
Goinf | Most inferior point of gonion area |
Golat | Most lateral point of gonion area |
Gopost | Most posterior point of gonion area |
Me | Most inferior point on symphysis of mandible |
Reference planes | Horizontal plane | A plane constructed by right Po, right Or and left Or |
Midsagittal plane | A plane perpendicular to the horizontal reference plane and passing through Na and Op |
Coronal plane | A Plane perpendicular to midsagittal and the horizontal planes and passing through Op |
Facial lines | Ramal height line | LineCdsup-Goinf |
Ramal lateral line | Line Cdlat-Golat |
Ramal posterior line | LineCdpost-Gopost |
Mandibular body line | Line Gopost-Me |