Occlusion


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occlusion

[ə′klü·zhən]
(anatomy)
The relationship of the masticatory surfaces of the maxillary teeth to the masticatory surfaces of the mandibular teeth when the jaws are closed.
(computer science)
In computer vision, the obstruction of a view.
(engineering)
The retention of undissolved gas in a solid during solidification.
(medicine)
A closing or shutting up.
(meteorology)
(physics)
Adhesion of gas or liquid on a solid mass, or the trapping of a gas or liquid within a mass.
(physiology)
The deficit in muscular tension when two afferent nerves that share certain motor neurons in the central nervous system are stimulated simultaneously, as compared to the sum of tensions when the two nerves are stimulated separately.

Occlusion

 

the absorption of a substance from a gaseous medium by solids or melts. During occlusion, gases are absorbed by the entire volume of the absorbent rather than by the surface layer. In this sense, occlusion is similar to absorption, which is the dissolution of gases in liquids.

The most common type of occlusion involves the absorption of gases by metals; for example, hydrogen is occluded by metals of Group VIII of the periodic table of elements. At room temperature, one volume of iridium absorbs more than 800 volumes of hydrogen, and one volume of palladium absorbs more than 700 volumes of hydrogen. The occluded gas interacts with the metal to form a solid solution; sometimes a part of the gas combines with the metal to yield other chemical compounds, for example, hydrides and nitrides.


Occlusion

 

(also bite), the relationship between the surfaces of the upper and lower teeth when in contact. The various forms of occlusion are established only when all the permanent teeth are present. With normal occlusion, each upper tooth, except the central incisors and the wisdom teeth, must touch the corresponding bottom tooth and the tooth behind it when the jaws are in contact. The sagittal surface passes between the central incisors of the upper and lower jaws.

There are four types of physiological occlusion. With orthognathous occlusion, the front teeth of the upper jaw cover the corresponding teeth of the lower jaw. Biprognathous occlusion is similar but with a more pronounced slant forward of the upper and lower teeth and of the alveolar processes. With a straight bite, the front teeth close on the edges of the incisors, and with an opisthognathous bite, the front teeth of both upper and lower jaws are inclined backward.

Pathological occlusion, which includes overbite, decreases the chewing efficiency of the teeth. It may be a congenital anomaly of development of the dentomaxillary system or a result of tooth removal or jaw disease or injury.

REFERENCES

Gavrilov, E. I., and I. M. Al’shits. Ortopedicheskaia stomatologiia. Moscow, 1970.
Kurliandskii, V. Iu. Rukovodstvo k prakticheskim zaniatiiam po ortopedicheskoi stomatologii, 3rd ed. Moscow, 1973.

A. I. RYBAKOV

occluded front

occluded frontclick for a larger image
Fronts formed by the merging of cold and warm fronts. If a cold front overtakes a warm front, the result would be an occluded front. Also known as a frontal occlusion or an occlusion. See also front.
References in periodicals archive ?
A possible explanation for the ongoing controversy about "occlusion" and "temporomandibular disorders" is definition-based.
Cheema et al., "Current perspectives on coronary chronic total occlusions. The Canadian multicenter chronic total occlusions registry," Journal of the American College of Cardiology, vol.
VanVeldhuisen et al., "SCORE study report 6-A randomized trial comparing the efficacy and safety of intravitreal triamcinolone with standard care to treat vision loss associated with macular Edema secondary to branch retinal vein occlusion: the Standard Care vs Corticosteroid for Retinal Vein Occlusion (SCORE) study report 6," Acta Ophthalmologic, vol.
Mar 2018 A biopharmaceutical company Clearside Biomedical, Inc, is creating first-in-class drug therapies to treat back-of-the-eye diseases, recently announced the registration of their first patient in Phase 3 clinical trial named TOPAZ of suprachoroidal CLS-TA used with an intravitreally administered anti-VEGF agent for the treatment of macular edema associated with Retinal Vein Occlusion. Clearside's exclusive suspension of the corticosteroid triamcinolone acetonide, Suprachoroidal CLS-TA, is created for the administration to the back of the eye through the suprachoroidal space, or SCS, which is the space situated in the middle of the choroid and the outer protective layer of the eye recognized as the sclera.
Impact of residual chronic total occlusion of right coronary artery on the long term outcome in patients treated for unprotected left main disease: the Milan and NewTokyo (MITO) registry.
The findings revealed that in subjects with canine guided occlusion, majority were with no occlusal interferences (56.2%) while in rest of the occlusal schemes, occlusal interferences were shown to be present as in group function (93.7%), combination (100%) and unclassified (100%).
Retinal vein occlusion: a form of venous thrombosis or a complication of atherosclerosis?
Table 3 shows a comparison of differences of means of recovery heart rate between protocol I (non-occlusion) and protocol II (occlusion) in both control and experimental groups using repeated measures ANOVA.
The resulting occlusion body suspension was used to inoculate groups of 12 fourth instars from the laboratory colony using the diet surface contamination technique of Lacey & Kaya (2007).
Computed tomography angiography revealed occlusion of the right MCA M1 segment (Figure 1c).