craniometer (kraniometer)

[= F. craniomètre = It. craniometro, craniometric, craniometrical (krāni-o-metrik, -ri-kal), a. [= F.craniométrique; as craniom eter + -ic, -ical.] Pertaining to craniometry. craniometry (krā-ni-om'et-ri), n. [= F. cra niométrie = It. craniometria; as craniometer + -y.] The measurement of skulls; the topographical relations ascertained by such measurements. The following are the points of measurement, lines, and angles upon which craniometry is based: the alveolar point, the point at the middle of the edge of the upper jaw, between the middle two incisors (4); the aster i on, the point behind the ear where the parie tal, temporal, and occipital bones meet ( B ); the auricu lar point, the center of the orifice of the external auditory meatus (C); the basion, the middle point of the anterior margin of the foramen magnum, corresponding in position to D; the bregma, the point of meeting of the coronal and sagittal sutures ( E ); the dacryon, the point on the side of the nose where the frontal, lacrymal, and superior maxillary bones meet ( F ); the glabella, the point in the median line between the superciliary arches, marked by a swelling, sometimes by a depre ion (G); the gonion, the point at the angle of the lower jaw ( H ); the inion, the external occipital protuberance ( I ); the jugal point, the point situated at the angle which the posterior border of the frontal branch of the malar bone makes with the superior border of its zygomatic branch (J); the lambda, the point of meeting of the sagittal with the lambdoidal suture ( K ); the malar point, a point situated on the tubercle on the external surface of the malar bone, or, when this is wanting, the intersection of a line drawn (nearly vertically) from the external extremity of the frontomalar suture to the tubercle at the inferior angle of the malar and a line drawn nearly horizontally from the inferior border of the orbit over the malar to the superior border of the zygomatic arch (L); the maximum occipital point, or occipital point, the posterior extremity of the anteroposterior diameter of the skull measured from the glabella in front to the most distant point behind, in the neighborhood of 0; the mental point, the middle point of the anterior lip of the lower border of the lower jaw ( P ); the metopic point, a point in the middle line between the two frontal eminences (Q); the nasion, or nasal point, the middle of the front on a sal suture at the root of the nose ( R ); the obelion, the part of the sagittal suture between the two parietal foramina (S); the ophryon, the middle of the supraorbital line which, drawn acro the narrowest part of the forehead, separates the face from the cranium: also called the supraorbital and supra nasal (T); the opisthion, the middle point of the posterior border of the foramen magnum ( U ); the pterion, the place where the frontal, parietal, temporal, and sphenoid bones come together (V); the step han i on, the point where the coronal suture cro es the temporal ridge ( W ); the subnasal point, the middle of the inferior border of the anterior nares at the base of the nasal spine: also called spinal point ( X ); and the supra - auricular point, the point vertically over the auricular point at the root of the zygomatic proce . The following craniometrical lines are distinguished: the facial line of Camper, a line tangent to the glabella and to the anterior surface and the basicranial axis. (See these terms, under axis1 and craniometry.) It varies with the extent to which the face lies in front of or below the anterior end of the cranium, from le than 90° to 120°. When it is great, the face is prognathous; when it is small, the face is orthogna thous. Huxley. - Craniofacial notch, in an at., a defect of parts in the midline between the orbital and nasal cavities.