Diastema


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diastema

[‚dī·ə′stē·mə]
(anatomy)
A space between two types of teeth, as between an incisor and premolar.
(cell and molecular biology)
Modified cytoplasm of the equatorial plane prior to cell division.

Diastema

 

an excessive interval or space between teeth in mammals, usually caused by reduction of part of the teeth. In most herbivorous animals the cuspids and sometimes the incisors are reduced. Similar diastemata occur in the upper and lower jaws of rodents, horses, kangaroos, and other animals. In ruminants, diastema occurs only in the lower jaw. In carnivores it takes place without reduction of teeth. One diastema occurs in front of the fangs of the upper jaw (providing space for the lower fangs), and another is behind the lower fangs (allowing room for the upper fangs during biting). In closing the jaws the fangs nest and form a solid closure, preventing lateral motion of the jaw and aiding in the holding of prey.

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Remarkable difference in perception among both groups was observed in picture of Diastema closure (pic 1), pink spot (pic 2), chalky white appearance (pic 9) and altered size of lateral incisor and canine (pic 11), which were marked "good" by non-dental students.
Variables Frequency, n (%) Missing teeth No 895 (55.5) Yes 717 (44.5) Anterior crowding No crowding 776 (48.1) One crowded segment 472 (29.3) Two crowded segments 364 (22.6) Anterior spacing No spacing 1.094 (67.9) One spaced segment 345 (21.4) Two spaced segments 173 (10.7) Diastema No 1.231 (76.4) Yes 381 (23.7) Upper anterior irregularity [less than or equal to] 2 mm 1.493 (92.6) > 2 mm 119 (7.4) Lower anterior irregularity [less than or equal to] 2 mm 1.564 (97.0) >2 mm 48 (3.0) Anterior open bite [less than or equal to] 2 mm 1.600 (99.2) > 2 mm 12 (0.7) Anterior maxillary overjet [less than or equal to] 4 mm 1.530 (94.8) > 4 mm 82 (5.2) Anterior mandibular overjet No 1.533 (95.1) Yes 79 (4.9) Table 4.
This dissatisfaction with dental appearance showed a statistical relationship with the adolescents' sex and with some of the occlusal components, such as the following: median maxillary diastema, mandibular irregularity, anterior open bite and the antero-posterior molar relation, evaluated by the Dental Aesthetic Index.
These include the total number of teeth in each mandibular ramus, that in "K." boyacensis is approximately 24, while in MP111209-1 is not greater than 18 (although the number of mandibular teeth may differ among individuals of the same species (Ketchum and Benson, 2011a)); the diastema is broader in "K." boyacensis than in MP111209-1; the rib facets of the posterior cervical vertebrae are divided anteroposteriorly into two areas in "K." boyacensis, but not in MP111209-1, and the propodials are slender in "K." boyacensis compared with those of MP111209-1(table 2).
The boys assigned similar median AC scores to photos D and E, which corresponded to severe dental diastema and mild anterior OB; and ascribed the lowest median AC score to mild ROJ and mild dental diastema.
The weak extension of the canine process and short diastema in Hexaprotodon can be considered the primitive characters of hippopotamids, occurring in taxa known from the late Miocene and early Pliocene (Coryndon, 1977, 1978; Geze, 1980; Harris, 1991).
If the patient has lost bone support, the center of resistance moves apically, and the same force against the crown produces greater pressure in the periodontal ligament of a periodontally compromised tooth than in a normally supported one intrusion of elongated incisors which is the logical solution to close the anterior diastema. [7, 8] Due to the risks of loss of the bone support around teeth and root resorption during intrusion, very light forces should be applied.
Cinco especies estan consideradas como endemicas de Mexico: Pseudoeurycea lineola, Micrurus diastema, Scincella silvicola, Drymarchon melanurus orizabensis y Drymobius margaritiferus margaritiferus, de las cuales, tres estan consideradas como endemicas de Veracruz (de dos solo las subespecies se consideran endemicas a Veracruz): Pseudoeurycea lineola, Drymarchon melanurus orizabensis y Drymobius margaritiferus margaritiferus.
diastema en el que se uso el modelo generado con los datos de calibracion (60% de los datos, 40% para su validacion), esto para evitar un sobreajuste, por la gran cantidad de registros que se tenia para esta especie.
It has been suggested that relapse might occur after treatment of small initial diastema (13) and measures must be taken to avoid relapse.
El foramen mental esta ubicado cerca al diastema. El proceso capsular del incisivo inferior es ligeramente globoso.
Por ultimo, Webb & Meachen, 2004, incluyeron a Hemiauchenia vera Matthew, 1909 en el genero Pleiolama como Pleiolama vera (Matthew, 1909) y consideran que Pleiolama difiere del genero Hemiauchenia por su pequeno tamano, corta diastema, premolares P1/1 y P3/3 largos, incisivos inferiores mas delicados y una sinfisis mas angosta.