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a structure of bowlike or curved outline.
abdominothoracic arch the lower boundary of the front of the thorax.
arch of aorta (aortic arch) the curving portion between the ascending aorta and the descending aorta, giving rise to the brachiocephalic trunk, the left common carotid artery, and the left subclavian artery.
aortic a's paired vessels arching from the ventral to the dorsal aorta through the branchial clefts of fishes and amniote embryos. In mammalian development, arch 1 largely disappears but may contribute to the maxillary and external carotid arteries; the dorsal portion of arch 2 persists and forms stems of the stapedial arteries; arch 3 joins the common to the internal carotid artery; arch 4 becomes the arch of the aorta and joins the aorta and subclavian artery; arch 5 disappears; and arch 6 forms the pulmonary arteries and, until birth, the ductus arteriosus.
branchial a's
four pairs of arched columns in the neck region of some aquatic vertebrates that bear the gills.
Branchial arches. From Dorland's, 2000.
pharyngeal arches.
dental arch either of the curving structures formed by the crowns of the upper and lower teeth in their normal positions (or by the residual ridge after loss of the teeth); they are called the inferior dental arch (see mandibular arch) and the superior dental arch (see maxillary arch).
a's of foot the longitudinal and transverse arches of the foot. The longitudinal arch comprises the medial arch or pars medialis, formed by the calcaneus, talus, and the navicular, cuneiform, and the first three tarsal bones; and the lateral arch or pars lateralis, formed by the calcaneus, the cuboid bone, and the lateral two metatarsal bones. The transverse arch comprises the navicular, cuneiform, cuboid, and five metatarsal bones.
lingual arch a wire appliance that conforms to the lingual aspect of the dental arch, used to secure movement of the teeth in orthodontic work.
mandibular arch
1. the first branchial arch, being the rudiment of the maxillary and mandibular regions; it also gives rise to the malleus and incus.
2. the dental arch formed by the teeth of the mandible; called also inferior dental arch.
maxillary arch the dental arch formed by the teeth of the maxilla; called also superior dental arch.
neural arch vertebral arch.
palatal arch the arch formed by the roof of the mouth from the teeth on one side to those on the other.
pharyngeal a's structures in the neck region of the human embryo that are analagous to the branchial arches in lower vertebrates; the four pairs of pharyngeal arches are mesenchymal and later cartilaginous structures that develop during the first two months of embryonic life and are separated by clefts (the pharyngeal grooves). As the fetus develops, the arches grow to form structures within the head and neck. Two of them grow together and enclose the cervical sinus, a cavity in the neck. Called also branchial arches.
pubic arch the arch formed by the conjoined rami of the ischium and pubis of the two sides of the body.
pulmonary a's the most caudal of the aortic arches; it becomes the pulmonary artery.
tendinous arch a linear thickening of fascia over some part of a muscle.
vertebral arch the dorsal bony arch of a vertebra, composed of the laminae and pedicles of a vertebra.
zygomatic arch the arch formed by the temporal process of the zygomatic bone and the zygomatic process of the temporal bone. See also anatomic Table of Bones in the Appendices.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Relating to both zygomatic bones or arches.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Age 43.34 10.86 22.5 63.5 WD 0.74 1.46 -1.55 4.0 16PF (Factor Q2) 22.84 7.24 7.0 38 EES 63.43 17.94 24 95 TAS-20 48.74 13.19 23 77 OAQ-G2 98.89 18.99 57 139 PPI-R 51.91 11.11 31 84 Factor 3 46.11 10.46 30 77 SD: Standard Deviation; WD: Width difference between bigonial arch (AG) and bizygomatic arch (AZ; WD = AZ--AG) in centimetres; 16PF (Factor Q2): Self-Reliance; EES: Emotional Expressivity Scale; TAS-20: Toronto Alexithymia Scale; OAQ-G2: Online Alexithymia Questionnaire; PPI-R (T): Psychopathic Personality Inventory-Revised (global score); and PPI-R (Factor 3): Coldheartness.
Those who accepted had their bizygomatic and bigonial arches measured in situ, using calipers (see in Instruments and procedure).
A high degree of correspondence has been found between visual, anthropometric and photometric measurements used to measure the bizygomatic and bigonial arch widths.
Regarding the comparison of groups with previously assessed psychological characteristics, subjects with the bizygomatic arch in contraction (group A) were more self-sufficient and showed less inclination to join in with the group.
Bizygomatic width was measured using a vernier caliper from the zygomatic prominence on one to the other side.
The facial measurements showed a wide range: Bizygomatic width ranged from 76.8mm-126.30mm.
A Pearson's correlation test was applied between width of central incisor and Bizygomatic width (p=0.11) Ratio found was 1: 19 compared to 1: 16 found in a study done on American caucasians by Berry.5
In the same region the bizygomatic width (Zr-Zl) is quite representative as well.
According to a global analysis, the indigenous children data are concentrated in the negative part of the first component, therefore they are distinguished by having the strongest bite force, highest dental arch transversal size and highest bizygomatic width as compared to the other two ethnic groups studied (Fig.
A reconstruction based on the parameters measured, will evidence that the individual is of the amazon Ticuna indigenous ethnia if the bite force, the dental arch transversal width and bizygomatic width is highest than the average values either for mestizo or afro.