Axis (redirected from opening axis)

axis /ax·is/ (ak´sis) pl. ax´es   [L.]

1. a line through the center of a body, or about which a structure revolves; a line around which body parts are arranged.

2. the second cervical vertebra.ax´ial

Axis. (A), (Top) transverse aspect; (bottom) superior aspect. (B), Position.

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basibregmatic axis  the vertical line from the basion to the bregma.

basicranial axis  a line from basion to gonion.

basifacial axis  a line from gonion to subnasal point.

binauricular axis  a line joining the two auricular points.

celiac axis  see under trunk.

dorsoventral axis  one passing from the back to the belly surface of the body.

electrical axis of heart  the resultant of the electromotive forces within the heart at any instant.

frontal axis  an imaginary line running from right to left through the center of the eyeball.

axis of heart  a line passing through the center of the base of the heart and the apex.

optic axis  the hypothetical straight line passing through the centers of curvature of the front and back surfaces of a simple lens.

Axes of the eye.

visual axis  an imaginary line passing from the midpoint of the visual field to the fovea centralis.

Axes of the eye.

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ax·is (kss)

n. pl. ax·es (ksz)

1. A real or imaginary straight line about which a body or geometric object rotates or may be conceived to rotate.

2. A center line to which parts of a structure or body may be referred.

3. The second cervical vertebra. Also called epistropheus, vertebra dentata.

4. An artery that divides into many branches at its origin.

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Axis

A line that passes through the center of the body or body part.

Mentioned in: Fractures

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axis,

n 1. an imaginary line around which motion occurs, as in an axis of rotation.
2. C2, the second cervical vertebra, around whose odontoid process the atlas rotates. See also atlas.

axes, transverse,

n axes located at the junctions of the frontal and horizontal planes, around which nutation and counternutation occur. Also called
z axes.

axis of rib motion,

n an imaginary line through the costovertebral and costotransverse rib articulations.

axis, anterior-posterior,

n axis located at the junction of the horizontal and sagittal planes. Also called the
x axis.

axis, anteroposterior rib (anˈ·t·rō·p·stēˑ·rē·ōr ribˑ aˑ·ksis),

n the imaginary line crossing between the sternum and the spinal column, about which the ribs rotate in bucket handle rib motion. See also axis of rib motion and bucket handle rib motion.

axis, hypothalamic-pituitary adrenal (HPA axis) (hī·pō·th·laˑ·mik pi·tōōˑ·i·ta·rē ·drēˑ·nl aˑ·ksis),

n major component of the neuroendocrine system that controls reactions to stress and manages metabolic function; involves interactions of the hypothalamus, pituitary gland, and adrenal glands.

axis, inferior transverse,

n a hypothetical axis passing from side to side through the lower auricular surface of the ilia and sacrum, describing iliac motion on the sacrum. Proposed by osteopathic physician Fred Mitchell, Sr. Also called the
innominate axis.

axis, longitudinal,

n a hypothetical axis located at the junction of a frontal and the median-sagittal planes. See also vertical axis.

axis, middle transverse,

n hypo-thetical axis for the nutation/counternutation of the sacrum, located horizontally through the front of the sacrum at the second segment. Proposed by osteopathic physician Fred Mitchell, Sr.

axis, postural,

n See axis, middle transverse.

axis, respiratory,

n See axis, superior transverse.

axis, sacral motion,

n movement of the sacrum around any of its axes.

axis, superior transverse,

n hypothetical axis around which involuntary sacral movement is believed to occur during the craniosacral cycle. The axis passes through the articular processes behind the dura mater's attachment point in the second vertebral segment of the sacrum. Proposed by osteopathic physician Fred Mitchell, Sr.

axis, vertical,

n axis located at the junction of the frontal and sagittal planes. Also called the
y axis. See also axis, longitudinal.

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axis (ak´sis),

n 1. a straight line around which a body may rotate.
n 2. the second cervical vertebra, which articulates with the first (atlas) and third cervical vertebrae.

axis, cephalometric,

n See axis, Y.

axis, condylar,

n an imaginary line through the two mandibular condyles around which the mandible may rotate during a part of the opening movement.

axis, condylar, determination,

n the location of the condylar axis by fixing a face-bow rigidly to the mandibular teeth, having the patient open and close the jaws, and recording the most posteriosuperior points of pure rotation with tattoo ink on the outer skin. See also face-bow and hinge-bow.

axis, condyle,

n one of three axes of the jaw condyles: (1) the hinge axis, an intercondyle imaginary line across the face through both condyles; whenever either condyle is chosen to be a rotator, it will display (2) a vertical axis, and (3) a sagittal axis. The hinge axis is a moving center for the opening and closing movements. The vertical axis is the center for the horizontal components of orbital movements. The sagittal axis is the center for the vertical components of orbital movements.

axis, hinge, -orbital plane,

n a craniofacial plane determined by three tattooed points. Two are located with one on each side of the face at the point of exit through the skin in front of the tragus of the imagined extended rearmost mandibular hinge axis. The third point is located on the right side of the nose at the level of the orbital rim just beneath the pupil when the patient is gazing directly forward. This plane corresponds to the anthropologic Frankfort plane.

axis, horizontal,

n See axis, hinge.

axis, long,

n an imaginary line passing longitudinally through the center of a body.

axis, mandibular,

n See axis, condylar.

axis of preparation,

n the path taken by a restoration as it slides on or off the preparation.

axis, opening,

n See axis, condylar.

axis, orbital movements of,

n.pl the movements projected on the axis-orbital plane in gathering the input data for an articulator.

axis, sagittal,

n the imaginary line around which the working condyle rotates in the frontal plane during lateral mandibular movement. The sagittal and vertical axes function concurrently.

axis shift,

n the imprecise term used before the nine different directionalized laterotrusions were discovered and named.

axis, vertical,

n the imaginary line around which the working condyle rotates in the horizontal plane during lateral mandibular movement. The sagittal and vertical axes function concurrently.

axis, Y,

n (cephalometric axis), the angle of a line connecting the sella turcica and the gnathion and related to a horizontal plane. An indicator of downward and forward growth of the mandible.

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Axis

genus of deer in family Cervidae.

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Axis axis

see axis deer.

Axis porcinus

see hog deer.

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axis

pl. axes [L., Gr.]

1. a line through a center of a body, or about which a structure revolves.

2. the second cervical vertebra.

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celiac axis

celiac trunk.

axis cylinder

axon.

dorsoventral axis

one passing from the back to the belly surface of the body.

electrical axis of heart

the resultant of the electromotive forces within the heart at any instant. See also mean electrical axis.

external bulbar axis

the optical axis that connects the anterior and posterior poles of the eyeball. Called also optic axis.

frontal axis

an imaginary line running from right to left through the center of the eyeball.

axis of heart

a line passing through the center of the base of the heart and the apex.

optic axis

see external bulbar axis (above).

orbital axis

a line passing through the apex of the bony orbit and the center of the opening of the orbit.

sagittal axis

an imaginary line extending through the anterior and posterior poles of the eye.

visual axis

an imaginary line passing from the midpoint of the visual field to the fovea centralis.