The definitions in this manual follow the Harris County Institute of Forensic Sciences published a Standard Operating Procedure (SOP) developed by Fleischman and Crowder (2018).
The full SOP is accessible under the external links page.
The full SOP is accessible under the external links page.
| Landmark | 3Skull Ref. | Interlandmark Distance Measure | Definition | Comments | Image |
|---|---|---|---|---|---|
| alare | al | NLB | Instrumentally determined as the most lateral points on the nasal aperture taken on the anterior surface. | Alare is taken on the anterior surface of the nasal margin (i.e., not inside the nasal aperture). | alare |
| alveolon | alv | MAL | The point on the interpalatal suture where the line drawn between the posterior ends of the alveolar ridges crosses the midline. | In order to take alveolon, the analyst should place a skinny rubber band on the alveolus prior to placing the cranium on the tri-column stand; take the point in the middle of the rubber band; touch, but do not depress the rubber band. | alveolon |
| asterion | ast | ASB | The point where the lambdoidal, parietomastoid, and occipitomastoid sutures meet. | asterion | |
| basion | ba | BBH, BNL, BPL, FML | Midline point at the anterior margin of the foramen magnum. | Basion is located on the midpoint of the foramen magnum margins. | basion |
| bregma | b | FRC, BBH, PAC, PAF, PAS | Point where the coronal and sagittal sutures intersect. | bregma | |
| cheek height (inferior point) | wmhi | WMH | The minimum distance, in any direction, from the lower border of the orbit to the lower margin of the maxilla, medial to the masseter attachment (inferior point). | cheek height inferior | |
| cheek height (superior point) | wmhs | WMH | The minimum distance, in any direction, from the lower border of the orbit to the lower margin of the maxilla, medial to the masseter attachment (superior point). | cheek height superior | |
| condylion laterale; (condylion) | cdl | bicondylar breadth | Lateral-most projection of the mandibular condyle. | condylion laterale | |
| condylion mediale | medcndl | Medial-most projection of the mandibular condyle. | condylion mediale | ||
| coronion | coron | Point at the tip of the coronoid process of the mandible. | coronion | ||
| dacryon | dk; d | OBB, DKB | Anterior border of the junction of the lacrimal and frontal. Apex of lacrimal fossa on the frontal bone. | Dacryon is located at the apex of the lacrimal fossa, on the frontal bone. Mark the point carefully with a pencil (unless marking with a pencil will cause damage) on both sides to assist with data collection. Details are provided below to help evaluate the location of this landmark: 1:In the ideal well-preserved specimen, the groove will be clearly defined with the apex corresponding well with the inner wall of the orbit as viewed by sighting. The groove will be bisected by the lacrimomaxillary suture, which will meet the fronto-lacrimal and frontomaxillary sutures (the frontal bone) at the groove's apex. The inner border of the orbit, curving down from above, will form a slight promontory overhanging the apex of the groove and just lateral to it. The point determined should be on the frontal bone (Howells 1973:167). 2: There is much variation from the above pattern: the fossa may be shallow with a broad or ill-defined apex; the suture may be obliterated; the lacrimal bone itself may be absent anatomically or lost postmortem. Approximate the point defined above, i.e., the apex, by using, in order of priority: the lacrimal fossa observed from directly above, a view which makes it easy to determine its course and the proper point of its apex; the promontory on the frontal bone the best guide when the lacrimal bone is broken out entirely; the posterior border of the fossa the point never lies posterior or lateral to it, but may approach it; the lacrimo-maxillary suture, when the structures are whole but the form of the fossa is shallow and undefined; there is often a small foramen just at the apex of the fossa, which may be used as a guide, though it is apt to lie slightly mesial to the apex proper (Howells 1973: 167). | dacryon |
| deepest point on nasal bone profile | ndspt | NDS, NDA | Calculated from nasal arc. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | |
| ectoconchion | ek; ec | OBB, EKB | The intersection of the most anterior surface of the lateral border of the orbit and a line bisecting the orbit along its long axis. | Ectoconchion is taken at the most anterior margin of the orbital rim. | ectoconchion |
| ectomolare | ecm | MAB | Widest part of the alveolar maxilla, around M2. | Ectomalare is located on the alveolus. Do not capture if the cranium is edentulous. | ectomolare |
| euryon; eurion | eu | XCB | Instrumentally-determined, ectocranial point of greatest cranial breadth. | eurion | |
| FOB point | fob | FOB | Foramen magnum breadth. | FOB point | |
| frontomalare anterior | fm:a | FMB, NAS | Point where the frontozygomatic suture intersects with the orbit. Point is taken anterior. | frontomalare anterior | |
| frontomalare temporale | fmt | UFBR | Point where the frontozygomatic suture crosses the temporal line. This is taken on the frontozygomatic suture at the most lateral point wherever that point may be. | frontomolare temporale | |
| frontotemporale | ft | WFB | Point generally anterior and medial along the temporal line on the frontal bone that, when paired with Frontotemporale, measures the minimum frontal breadth. | frontotemporale | |
| glabella | g | GOL | The most forwardly projection point in the mid-sagittal plane at the lower margin of the frontal bone. | glabella | |
| gnathion | gn | GNI | The most inferior midline point on the mandible. | gnathion | |
| gonion | go | GOG | The most lateral external point at the junction of the horizontal and ascending rami. | gonion | |
| HMF inferior point | hmfipt | HMF | Mandibular body height at the mental foramen. (inferior point) | HMF inferior point | |
| HMF superior point | hmfspt | HMF | Mandibular body height at the mental foramen. (superior point) | HMF superior point | |
| hormion | The most posterior midline point on the vomer. | Hormion is taken posterior to the vomer at the midline, not into the anterior deflection if it is present. | hormion | ||
| infradentale | id | GNI | The midline point on the alveolar bone between the two central mandibular incisors. | infradentale | |
| jugale | ju | JUB | Deepest curvature of the zygomatic angle, taken laterally, not on the margin. | Jugale is taken on the postero-lateral angle on the lateral surface. | jugale |
| krotaphion | kro | The superior-posterior tip of the greater wing of the sphenoid. | Krotaphion cannot be taken when there is frontal-temporal articulation, a notch bone is present, or the sutures are obliterated. | krotaphion | |
| lambda | la; l | PAC, PAF, PAS, OCC | Point where the sagittal and lambdoindal sutures meet. | lambda; lambda corrected |
|
| lower orbital border | obhi | OBH (inferior point) | The height between the upper and lower borders of the left orbit, perpendicular to the long axis of the orbit and bisecting it. Internal measurement. | lower orbital border | |
| M1 anterior point | avrpt | XRL, MAN | Anterior/mesial margin of the left first molar, on the alveolus. | M1 anterior point is located on the alveolus. M1 anterior point is not located between the roots of the first molar and second premolar. Do not capture if the cranium is edentulous. | M1 anterior point |
| mandibular angle base | manlipt | MAN | Point on the posterior base of the mandible as if you were measuring ramus height with a mandibulometer. | ||
| marginal process lateral | mpl | Point at the lateral-most aspect of the marginal process of the zygomatic. | Marginal process is taken postero-laterally. | marginal process lateral | |
| mastoidale | ms | MDH | Point at the most inferior tip of the mastoid. | mastiodale | |
| maximum frontal point | xfb | XFB | Instrumentally-determined, maximum frontal breadth; on the coronal suture. | max. frontal point | |
| maximum malar projection point L/R | MLS | Calculated from malar arc. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | ||
| metopion | met | FRF, FRS | Instrumentally-determined, point where the frontals elevation above the chord from nasion to bregma is greatest. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | metopion |
| most inferior nasal border; nariale | nlhi | NLH | Actual floor of the nasal cavity, taken inside the nasal aperture if there is gutternig or the stylus will fit into the nasal aperture. If there is a nasal sill, place stylus on the anterior surface of the maxilla to approximate the location of nasal floor. | Most inferior nasal border (i.e., actual floor of the nasal cavity) is taken inside the nasal aperture if there is nasal guttering. If there is a nasal sill, and you cannot reach the stylus inside the nasal aperture (to reach the floor), then place the stylus on the anterior surface of the maxilla to approximate the location of the nasal floor. In 3Skull, Most Inferior Nasal Border is used to calculate nasal height (NLH)the right and left sides are averaged. | most inferior nasal border |
| nasal bone elevation | sispt | SIS, SIA | Calculated from the nasal arc. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | |
| nasale inferius | nasi | The most inferior point of the nasomaxillary suture, where the nasal touches the maxilla. | Termination of the intersection of the nasomaxillary suture, discounting any nasal bone overgrowth. (Spradley, personal communication). | nasale inferius | |
| nasale superius | The most superior point of the nasomaxillary suture, where the nasal touches the maxilla. | nasale superius | |||
| nasion | na | BNL, FRC, NAS, NBA, NLH, NLB, NOL, NPH, UFHT | Point of intersection of the nasofrontal suture and the mid-sagittal plane, on the frontal bone. | nasion | |
| nasomaxillary suture pinch | wnb | WNB, Simotic chord | The minimum transverse breadth across the two nasal bones. | nasomaxillary suture pinch | |
| occipital subtense point | OCF, OCS | The maximum subtense, at the highest point on the convexity along the lambda-opisthion chord, in midline. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | ||
| opisthion | os; o | FOL | Midline point at the posterior margin of the foramen magnum. | Opisthion is located on the midpoint of the foramen magnum margins. | opisthion |
| opisthocranion | op | GOL | Instrumentally-determined, the furthest point from glabella in midline. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | |
| parietal subtense point | PAF, PAS | The maximum subtense, at the highest point on the convexity of the parietal bones, within the bregma-lambda chord, in midline. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | ||
| pogonion | malapt | XRL, MAN | Most anterior midline point on the chin of the mandible. | pogonion | |
| porion | por | MDH | Point at the most superior aspect of the EAM. | porion | |
| prosthion (Howells) | prosH | BPL, NPH, MAL | Midline point at the most anterior point on the alveolar process of the maxillae. | prosthion (Howells) | |
| prosthion (Martin) | prosM | UFHT | Midline point at the inferior tip of the alveolar process of the maxilla. | prosthion (Martin) | |
| radiculare | ra | AUB | Deepest point on the zygomatic root (bi-auricular breadth). | radiculare | |
| radiometer point | radpt | radii NAR, BRR | Taken inside the EAM, floating. | Radiometer point is taken by inserting the stylus tip all the way into the EAM, then pulling it half way out, taking the measurement with the stylus floating in the cavity rather than against the wall. The stylus should be level with the imaginary straight line connecting the two EAMs. One way to do this is to place both index fingers outside of the EAMs to help visualize the connecting line. Visualizing taking this point with a radiometer is helpful. | radiometer point |
| sphenion | sph | The anterior tip of the parietal. | Sphenion cannot be taken when there is frontal-temporal articulation, a notch bone is present, or the sutures are obliterated. | sphenion; sphenion 2 |
|
| sphenofrontale | spheno-fronto-zygomatic | Point where the sphenoid, frontal, and zygomatic sutures intersect. | sphenofrontale | ||
| staurion | The point at the intersection of the median and transverse palatine suture. | Staurion may be difficult if the sutures meet unevenly. When this occurs, draw lines to create a point of intersection. | staurion | ||
| stephanion | stp | STB, STS | Point where the coronal suture crosses the temporal line (left and right). | stephanion | |
| subspinale | ss | SSR, SSS | The deepest point seen in the profile below the anterior nasal spine. | If there is a gap between the maxillae below the nasal spine, DO NOT insert the stylus into the gap. | subspinale |
| superior condyle | Highest point on the mandibular condyle. | superior condyle posterior | |||
| superior condyle posterior | CDL, MAN | Perpendicular to the highest point on the mandibular condyle as if it were sitting in a mandibulometer. | |||
| supraglabellare | GLS | The point at which the convex profile of the frontal bone changes to join the prominence of the glabellar region. | supraglabellare | ||
| TMF buccal point | tmfbpt | TMF | Mandibular body breadth at the mental foramen. | TMF buccal point | |
| TMF lingual point | tmflpt | TMF | Mandibular body breadth at the mental foramen. | TMF lingual point | |
| upper orbital border | obhs | OBH (superior point) | The height between the upper and lower borders of the orbit, perpendicular to the long axis of the orbit and bisecting it. Internal measurement. (superior point) | upper orbital border | |
| vertex radius point | VRR | Instrumentally-determined, the highest point at midline when the skull is in Frankfurt Horizontal. | Point is automatically calculated, no need to digitize. Not included in the LAMbDA models. | ||
| WRB anterior point | wrbapt | Minimum ramus breadth. (anterior point) | WRB anterior point | ||
| WRB superior/posterior point | wrbppt | The minimum ramus breadth. (posterior point) | WRB superior/posterior point | ||
| zygion | zyg | ZYB | The most laterally positioned point on the zygomatic arches. The position of zygion is defined from the measurement of bizygomatic breadth. | zygion | |
| zygomaxilare | zygom | ZMB, IML | Intersection of the zygomaxillary suture and the limit of the attachment of the masseter muscle, on the facial (most anteriorly projecting) surface of the zygomaxillary suture. | zygomaxilare | |
| zygoorbitale | zo | MOW, IML, XML | The intersection of the orbital margin and the zygomaticomaxillary suture. | Since the orbital border is usually softly rounded here, the point should be found midway between the facial and orbital surfaces. A small process or sliver of the malar may extend several millimeters medially from the rest of the bone just here, pushing the suture and point well inward along the orbital margin. As a convention, the point is never placed medial to the plane of the medial border of the infraorbital foramen (Howells 1973: 170). | zygoorbitale |
| zygotemporale inferior | imlpt | IML, XML | Point at the inferior zygotemporal suture on the zygomatic process. | zygotemporale inferior | |
| zygotemporale superior | szs | IML, XML | Point at the superior zygotemporal suture on the zygomatic process. | zygotemporale superior |
