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Table 1 The reference point, line, and the plane

From: Three-dimensional analysis of the anterior loop of the inferior alveolar nerve in relation to the growth pattern of the mandibular functional subunit

Landmarks Abbreviation Description
Point
 Nasion Na The middle point of the junction of the frontal and the two nasal bones
 Porion Po The highest point of the skeletal external auditory meatus (PoR, right side; PoL, left side; PoC, center of the PoR and PoL, automatically determined)
 Orbitale Or The lowest point in the lower margin of the bony orbit (OrR, right side; OrL, left side; OrC, center of the OrR and OrL, automatically determined)
 Pogonion Pog The most anterior point of the mandible in the midline
 Mental foramen MF The center of mental foramen (MFR, right side; MFL, left side)
 Gonion Go The most inferior, posterior, and lateral point of the angle of the mandible (GoR, right side; GoL, left side)
 Sigmoid notch SN The deepest point between the condylar and coronoid process of the mandible (SNR, right side; SNL, left side)
Line
 FH line   A line projecting the PoC and OrC
Plane
 McNamara plane pMcN A plane through the nasion and perpendicular to the FH line
 Occlusal plane pOcc A plane through the bilateral mandibular first molar mesiobuccal cusp and the middle of the lower incisal edge
 MF_H plane pMF_H A plane through the MF point and parallel to the pOcc
 MF_V plane pMF_V A plane through the bilateral MF and perpendicular to the pOcc