denticle

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denticle

[′dent·ə·kəl]
(zoology)
A small tooth or toothlike projection, as the type of scale of certain elasmobranchs.
References in periodicals archive ?
The most common finding was posterior uveitis manifesting as placoid chorioretinitis (58%), which has been noted in previous reports (14,23,29-31).
Spectral domain optical coherence tomography showed the placoid lesions with disruption of the RPE, external limiting membrane, and ellipsoid zone as well as small focal points of hyperreflective material at the level of the ellipsoid zone (Figure 1(c)).
Bilateral lesions are aspects of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) with progressive evolution in serpiginous choroiditis, probably of infectious etiology.
Raschi W Tabit C (1992) Functional aspects of placoid scales: a review and update.
It is mainly caused by the improved barrier properties: upon heating of the material, the placoid nanoparticles can prevent the diffusion of oxygen and remove the thermal decomposition of volatile products of the polymer [23, 30, 31].
Distal inner labral sensilla: one central placoid, flanked at a distance by a pair trichoid-placoid.
Five distal inner labral sensilla, a central placoid, flanked at a distance by a pair trichoid-placoid.
Stylet support insertion 10 12.1-21.8 61.4-67.6 Buccal tube width 10 1.9-3.4 6.7-11.2 First macroplacoid 10 1.3-3.7 5.2-12.4 Second macroplacoid 10 1.2-2.6 6.0-8.6 Third macroplacoid 10 1.2-2.9 4.7-10.0 Macroplacoid row 10 5.6-10.9 26.3-36.6 Microplacoid 7 0-2.6 0-7.9 Placoid row 7 10.4-34.7 34.6-46.0 Primary claw branch, Leg I 10 5.5-9.7 23.1-32.6 Secondary claw branch, Leg I 10 4.0-7.0 16.4-23.1 Primary claw branch, Leg II 10 6.3-10.5 27.4-35.2 Secondary claw branch, Leg II 10 3.6-7.9 16.8-27.1 Primary claw branch, Leg III 10 6.5-9.8 27.9-34.3 Secondary claw branch, Leg III 10 3.4-8.0 16.0-26.8 Primary claw branch, Leg IV 10 6.7-13.6 26.9-45.6 Secondary claw branch, Leg IV 10 4.5-9.9 19.3-33.2 Mean Character Length pt Body 304.2 n.a.
Inflammatory etiologies include uveitis-glaucoma-hyphema syndrome, sympathetic ophthalmia, sarcoidosis, pars planitis, multiple sclerosis, rheumatoid arthritis, birdshot chorioretinopathy, Behcet disease, Vogt-Koyanagi-Harada disease, sterile endophthalmitis, multifocal choroiditis, and acute posterior multifocal placoid pigment epitheliopathy.
The teeth of sharks are merely modified and enlarged dermal denticles, so it is not surprising that the teeth are almost identical in their structure with the placoid scales.
15 In marine life, the terms cycloid and placoid refer to which part of a fish?