long axis

long axis

n.

A line parallel to an object lengthwise, as in the body the imaginary line that runs vertically through the head down to the space between the feet.

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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.