pISSN 2234-7518
eISSN 2005-372X
eISSN 2005-372X
Landmarks and reference planes used in this study
| Landmark | Definition |
|---|---|
| Skeletal | |
| Or | The most inferior point of the lower orbital margin |
| Po | The most superior point of the external auditory meatus |
| Cg | The most superior point on the crista galli |
| Op | The midpoint of the posterior border of the foramen magnum |
| Go | The most inferior point of gonial angle on the lateral view |
| Cd | The most superior point of the condylar head |
| Me | The most inferior point on the symphyseal outline |
| MF | The most inferior point of the mental foramen |
| MFmid | The midpoint of the MF of both sides |
| PM | The point where the curvature changes from concave to convex at the most anterior symphyseal border |
| Dental | |
| UM | The central fossa of the maxillary first molar |
| UC | The cusp tip of the maxillary canine |
| LM | The central fossa of the mandibular first molar |
| LC | The cusp tip of the mandibular canine |
| Soft tissue | |
| G’ | The most anterior midpoint of the forehead |
| N’ | The most posterior midpoint on the contour of the nasal root |
| Prn | The most anterior midpoint of the nasal tip |
| Sn | The midpoint located at the junction of the nasal columella and upper lip |
| Al | The most lateral point on each nasal alar contour |
| Ac | The most posterior point on each alar-facial groove |
| Ls | The midpoint of the vermilion line of the upper lip |
| Li | The midpoint of the vermilion line of the lower lip |
| Stms | The most inferior midpoint of the lower border of the upper lip |
| Stmi | The most superior midpoint of the upper border of the lower lip |
| NLF | The most posterior point on each nasolabial fold at the vertical level of the midpoint of Sn and Ls |
| Ch | The most lateral point on each labial commissure |
| B’ | The most posterior midpoint on the mentolabial sulcus |
| Pog’ | The most anterior midpoint of the chin |
| Me’ | The most inferior midpoint on the lower contour of the chin |
| Subchin | The point on each lower contour of the chin at the 15mm lateral to Me’ |
| Midchin | The point on each chin contour at the level of the midpoint of Ch and Subchin |
| Reference plane | |
| Frankfort horizontal plane (FHP) | The plane passing by Po of both sides and right Or |
| Midsagittal plane (MSP) | The plane passing by Cg and Op, perpendicular to the FHP |
| Coronal plane | The plane passing by Cg, perpendicular to the FHP and MSP |
| Mandibular horizontal plane (MHP) | The plane passing by three points, bilateral MFs and PM |
| Mandibular midsagittal plane (MnMSP) | The plane passing by Me and MFmid, perpendicular to the MHP |
Or, orbitale; Po, porion; Cg, crista galli; Op, opisthion; Go, gonion; Cd, condylion; Me, menton; MF, mental foramen; PM, protuberance menti; UM, maxillary first molar; UC, maxillary canine; LM, mandibular first molar; LC, mandibular canine; G’, soft tissue glabella; N’, soft tissue nasion; Prn, pronasale; Sn, subnasale; Al, nasal ala; Ac, nasal alar curvature; Ls, labrale superius; Li, labrale inferius; Stms, stomion superius; Stmi, stomion inferius; NLF, nasolabial fold; Ch, cheilion; B’, soft tissue B point; Pog’, soft tissue pogonion; Me’, soft tissue menton.