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2. the trapping of a liquid or gas within cavities in a solid or on its surface.
3. the relation of the teeth of both jaws when in functional contact during activity of the mandible.
4. momentary complete closure of some area in the vocal tract, causing breathing to stop and pressure to accumulate.
Normal occlusion of the primary molars. From Darby and Walsh, 1994.
abnormal occlusion malocclusion.
central occlusion (centric occlusion) occlusion of the teeth when the mandible is in centric relation to the maxilla, with full occlusal surface contact of the upper and lower teeth in habitual occlusion.
coronary occlusion see coronary occlusion.
eccentric occlusion occlusion of the teeth when the lower jaw has moved from the centric position.
functional occlusion contact of the maxillary and mandibular teeth that provides the highest efficiency in the centric position and during all exclusive movements of the jaw that are essential to mastication without producing trauma.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(ŏ-klū'zhŭn), Do not confuse this word with atresia or stenosis.
1. The act of closing or the state of being closed.
2. In chemistry, the absorption of a gas by a metal or the inclusion of one substance within another (as in a gelatinous precipitate).
3. Any contact between the incising or masticating surfaces of the upper and lower teeth.
4. The relationship between the occlusal surfaces of the maxillary and mandibular teeth when they are in contact.
[L. oc-cludo, pp. -clusus, to shut up, fr. ob., against, + claudo, to close]
Farlex Partner Medical Dictionary © Farlex 2012


a. The process of occluding.
b. Something that occludes.
2. Medicine An obstruction of an anatomical passage, as of an artery by plaque.
3. Dentistry The alignment of the teeth of the upper and lower jaws when brought together.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Cardiovascular disease
Obstruction of a vessel.
Closure of the upper and lower molars.

The complete closure of an orifice.
The covering of one eye, either totally or partially, to prevent or reduce visual stimulation.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


1. The complete closure of a vessel with gas, liquid or solid.
2. Obstruction.
3. Closure of the upper and lower molars. See Acute vascular occlusion, Aortic occlusion, Central retinal artery occlusion, Malocclusion.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


1. The act of closing or the state of being closed.
2. In chemistry, the absorption of a gas by a metal or the inclusion of one substance within another (as in a gelatinous precipitate).
3. Any contact between the incising or masticating surfaces of the upper and lower teeth.
4. The relationship between the occlusal surfaces of the maxillary and mandibular teeth when they are in contact.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


(o-kloo'zhun) [L. occlusio, a closing up]
1. The acquired or congenital closure, or state of being closed, of a passage. Synonym: imperforation
2. Alignment of the mandibular and maxillary teeth when the jaw is closed or in functional contact. Synonym: dental occlusion See: malocclusion
3. The covering of an eye in order to improve vision in the other, e.g., in treating strabismus.

acquired centric occlusion

Centric occlusion.

abnormal occlusion


adjusted occlusion

See: equilibration

anatomical occlusion

In dentistry, an occlusion in which the posterior teeth of a denture have masticatory surfaces that resemble natural, healthy dentition and articulate with the surfaces of similar or opposing teeth. The opposing teeth may be artificial or natural.

arterial occlusion

A blockage of blood flow through an artery. It may be acute or chronic and occurs, for example, in coronary or in peripheral arteries. Patients with acute arterial occlusion have severe pain (as in angina pectoris), decreased or absent pulses, and mottling of the skin of an affected extremity. The occlusion is removed and blood flow restored if possible.

balanced occlusion

The ideal and equal contact of the teeth of the working side of the jaw by the complementary contact of the teeth on the opposite side of the jaw. Synonym: balanced bite

central retinal artery occlusion

Abbreviation: CRAO
Blockage of blood flow to the retina (that is, to the central retinal artery or one of its branches), resulting in sudden visual loss. The condition usually affects one eye. When the retinal artery is blocked by a blood clot, early thrombolysis sometimes provides sight-preserving therapy.


CRAO is typically caused by a tiny embolus that lodges in the retinal circulation. It usually occurs in people with high blood pressure, diabetes mellitus, cardiac valve disease, or atrial fibrillation, which predispose to atherosclerosis or arterial embolization. Other causes include inflammatory or autoimmune diseases affecting the circulation (arteritis), clotting disorders, hyperlipidemia, injected drugs or contaminants, and tumor metastases.

centric occlusion

In dentistry, the vertical and horizontal position of the mandible that produces maximal interdigitation of the cusps of the maxillary and mandibular teeth. This is the ideal position or type of occlusion. Synonym: acquired centric occlusion; habitual centric occlusion; intercuspal position
Enlarge picture

coronary occlusion

Complete or partial obstruction of a coronary vessel by thrombosis or as a result of spasm. Synonym: cardiac thrombosis; coronary thrombosis
See: myocardial infarction; illustration

dental occlusion

Occlusion (2).

eccentric occlusion

Any dental occlusion other than centric.

habitual occlusion

The usual relationship between the teeth of the maxilla and mandible that represents the maximum contact. This occlusion varies from person to person and is seldom ideal or true centric occlusion.

habitual centric occlusion

Centric occlusion.

occlusion of the pupil

In the eye, a pupil with an opaque membrane shutting off the pupillary area.

traumatic occlusion

Injury to the tissues that support the teeth because of malocclusion, missing teeth, improper chewing habits, or a pathological condition that causes a person to chew abnormally.

working occlusion

The usual method of contact of teeth as the mandible is moved to one side during chewing.
Medical Dictionary, © 2009 Farlex and Partners


1. Closing off or covering of an opening, or obstruction to a hollow part.
2. The relationship of the biting surfaces of the teeth of the upper and lower jaws.
3. The deliberately covering of one eye for periods of weeks or months in the treatment of AMBLYOPIA in children.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


blocking off, closing.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005


The way upper and lower teeth fit together during biting and chewing.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


The act of blocking or the state of being blocked. Examples: vision with an occluder, a vessel with an embolus.
occlusion amblyopia See amblyopia; occlusion treatment.
o nystagmus See occlusion nystagmus.
punctal occlusion Sealing of the lacrimal punctum, temporarily (e.g. with a plastic plug) or permanently (e.g. by heat cauterization), to preserve the natural tears or prolong the effect of artificial tears. This method is commonly used in the management of keratoconjunctivitis sicca. Occasionally a plug made of collagen is used prior to insertion of a more permanent type of punctal plug, because it dissolves within a week. This is done to determine whether permanent or semi-permanent occlusion (as with a silicone plug) is likely to succeed. See neurotrophic keratopathy.
retinal arterial occlusion See retinal arterial occlusion.
retinal vein occlusion See retinal vein occlusion.
occlusion test See cover test.
occlusion treatment A method of treating amblyopia or strabismus by covering the good eye. Such a method is most effective below the age of four years and with little effect after the age of nine years, that is beyond the critical period of development. However, this technique must be used with caution as prolonged occlusion in very young children can lead to a reversal of eye dominance in which the previously good eye becomes amblyopic (called occlusion amblyopia). Moreover, it has been shown that the effect of occlusion does not improve beyond six hours at a time. Alternate occlusion is preferred as both eyes are thus stimulated. Syn. patching See form-deprivation myopia; penalization; critical period; pleoptics.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann


1. The act of closing or the state of being closed.
2. Any contact between the incising or masticating surfaces of upper and lower teeth.
3. Relationship between occlusal surfaces of maxillary and mandibular teeth when in contact.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Considering the topic "occlusion" in the dental literature, this term is used for 4 different entities: (1) the anatomic or "orthodontic" jaw relation: the Angle classification, (2) static contact between the teeth of the upper and lower jaws, (3) dynamic contact between the teeth of the upper and lower jaws, for example, cuspid guidance versus group function, articulation, and occlusal interferences, and (4) the prosthetic classifications, more specifically, the complete/incomplete dentition versus complete dentitions and the presence of fixed/removable prosthetics.
Giubilato et al., "Management strategies in patients affected by chronic total occlusions: results from the Italian registry of chronic total occlusions," European Heart Journal, vol.
Greenberg, "Anti-vascular endothelial growth factor for macular oedema secondary to central retinal vein occlusion," Cochrane Database of Systematic Reviews, vol.
Survival after percutaneous coronary intervention for complete total occlusion. Clini Res Cardiology 2016; 105(11): 921-9.
While considering the relevance of occlusal scheme to the gender related scheme it was found in our study that both genders have high percentage of group function as observed in similar studies done earlier by Koc et al, where they found it to be statistically insignificant.13 Study done earlier have observed canine guided occlusion to be the more prevalent in adolescence, however group function was more common and predom-inantantly found with increased age.Non carious tooth surface loss can be attributed to the transformation of canine guided occlusion to the group function.14
Genetic polymorphisms associated with retinal vein occlusion: a Greek case-control study and meta-analysis.
Table 4 shows the heart rate during various phases of recovery, with and without occlusion protocol (protocol I and protocol II).
To produce a pooled sample representing all the virus variants present in the population, isolates amplified in the previous step were thawed, occlusion bodies extracted in 1 mL sterile water and counted using a Neubauer cell counting chamber (Hawksley, Lancing, United Kingdom).
Catheter angiography of the right internal carotid artery revealed distal M1 occlusion of the right MCA in addition to severe stenosis of the proximal M2 segment just beyond the clot (Figure 1d).
The European Society of Cardiology (ESC) Guidelines for the management of AMI in patients with ST segment elevation [4] recognized atypical electrocardiographic presentations that should prompt a primary percutaneous coronary intervention strategy in patients with ongoing symptoms consistent with myocardial ischemia: bundle branch block, ventricular paced rhythm, isolated posterior MI (ST segment depression [greater than or equal to] 0.5 mm in leads V1 --V3, and elevation in V7-V9 [greater than or equal to] 0.5), and ischemia due to left main coronary artery occlusion with ST depression [greater than or equal to] 1 mm in eight or more surface leads (inferolateral ST depression), associated with ST segment elevation in aVR and/or V1.
Classification of central retinal vein occlusion. Ophthalmology 1983; 90:458-74.
We aimed to compare the treatment results and outcomes of two patient groups to which we gave IV rt-PA treatment alone, involving patients with isolated middle cerebral artery (MCA) occlusion and those with no large vessel occlusion in our stroke center.