Table 1 Definitions of the selected anatomical landmark and reference planes
Abbreviation | Measurement parameters | Definition |
|---|---|---|
Anatomical Landmark | Â | |
(Me) | Menton | The most inferior midpoint on the symphysis |
(Gn) | Gnathion | The midpoint of the symphysis |
(Pg) | Pogonion | The most anterior and midpoint on the symphysis of the mandible |
(L1) | L1 | Midpoint of the lower incisor edge. |
(U1) | U1 | Midpoint of the upper central incisors edge |
(ANS) | Anterior Nasal Spine | The maxillary anterior nasal spine’s most anterior point |
(Na) | Nasion | Anterior and superior frontonasal suture |
(Ba) | Basion | The foramen magnum’s inferior-anterior margin in the skull base midline |
(S) | Sella | The center point of the pituitary fossa is in the middle cranial fossa in sagittal and axial views. |
(Or) | Orbital | The midpoint of the infraorbital margin. |
(Po) | Porion | the most outer and superior bony points of the external acoustic meatus. |
Reference Planes | ||
F/MSP | Facial/midsagittal plane | The plane constructed by (N), (BA), and (ANS) passes through (N) as the coordinate origin. |
HP | Horizontal plane | A plane parallel to Or-FMSP passes through (N) as the coordinate origin. |
CP | Coronal plane | A plane parallel to Or-FMSP passes through (N) as the coordinate origin. |