Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "mandible shape" wg kryterium: Temat


Wyświetlanie 1-2 z 2
Tytuł:
Ocena kształtu żuchwy na podstawie obrazowania w tomografii wolumetrycznej
Examination of mandible shape based on imaging in Cone Beam Computed Tomography
Autorzy:
Ryniewicz, A. M.
Ryniewicz, W.
Olszewska, M.
Powiązania:
https://bibliotekanauki.pl/articles/157382.pdf
Data publikacji:
2013
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
analiza wymiarowa
CBCT
model wirtualny
parametry kształtu żuchwy
dimensional analysis
virtual model
mandible shape parameters
Opis:
Celem pracy była weryfikacja dokładności odwzorowania parametrów kształtu żuchwy z wykorzystaniem tomografii wolumetrycznej (CBCT) i pomiarami wykonanymi dla potrzeb diagnostyki klinicznej. Pomiary referencyjne przeprowadzono na współrzędnościowej maszynie pomiarowej. Preparaty poddano obrazowaniu CBCT i opracowano wirtualne modele żuchwy. Analizowano parametry: trójkąt Bonwille’a, płaszczyznę okluzyjną, oraz symetrię żuchwy względem płaszczyzny strzałkowej. Niepewność standardowa przeprowadzonych pomiarów wynosiła od 0,25 mm do 1,15 mm.
A novel dental imaging technique is Cone Beam Computed Tomography – CBCT. The aim of the project was to verify the accuracy of the projection of shape parameters of a mandible applying the CBCT and measurements taken for needs of clinical diagnostics. The study was based on cadaver specimens. The reference measurements were made on a coordinate-measuring machine. Then, the specimens were exposed to the imaging using CBCT. A verification study consisted in measuring the physical geometrical characteristics of a clinically-applied object. The measurements resulted from the study of real-world objects and also three dimensional models created on the basis of two dimensional images from CBCT (Fig. 3). A Bonwille’s triangle and the occlusal plane (Figs. 4, 5) served as the geometrical parameters of the jawbone shape. Additionally, the sagittal plane, in relation to which the jawbone symmetry was estimated, was defined and specified (Figs. 7, 8). Three measurement series for the coordinate-measuring machine and five measurements for the CBCT, taken for each point, were held to specify the coordinates as well as the lengths of the sections between the characteristic points. 20 measurements of the lengths of the sides of the Bonwille’s triangle were taken for the purpose of statistical analysis and evaluation of the accuracy of measurements taken by CBCT. In all studied specimens, the asymmetric location of the points was detected, especially B and C points, which were located on the joint surface of the mandible head. Simultaneously, K and L points were located on the coronoid bones and F, G points on the passage of the mandible canal into its ramus. The coordinate-measuring machine was used for the reference measurements. The specimens were subjected to the CBCT imaging and the virtual jawbone models were prepared. The parameters that were analysed were: Bonwille’s triangle, occlusal plane and the jawbone symmetry in relation to the sagittal plane. The standard uncertainty of thetaken measurements fluctuated between 0,25 mm and 1,15 mm.
Źródło:
Pomiary Automatyka Kontrola; 2013, R. 59, nr 3, 3; 239-242
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Morphological disparity in Plio-Pleistocene large carnivore guilds from Italian Peninsula
Autorzy:
Meloro, C.
Powiązania:
https://bibliotekanauki.pl/articles/22061.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Carnivora
Italian Peninsula
Italy
morphological diversity
Pleistocene
Plio-Pleistocene
Quaternary
geometrical morphometry
large mammal
mandible shape
paleontology
morphological variability
taxonomy
Opis:
Communities of large mammals exhibit changes in morphological diversity through space and time; changes that are possibly correlated to distinct aspects of the physical environment. Here, I explore shape changes in the trophic apparatus of large carnivore guilds, comparing extant communities with Quaternary ones, from peninsular Italy. Mandibular shape is quantified through geometric morphometrics and its disparity is computed for each carnivore guild. Patterns of morphospace occupation through space and time reveal that extant carnivore guilds are negatively influenced by number of artiodactyls. Very productive ecosystems show low values of morphological disparity because species tend to occupy central regions of the morphospace rather than extreme areas. Disparity of mandibular corpus shape remains relatively stable throughout the Quaternary in the large carnivore communities of the Italian peninsula. They exhibit similar values to extant guilds because the trophic apparatus did not evolved important morphological novelties. Interestingly, carnivore guilds of the late Pliocene (3.5 Ma) and early Pleistocene (0.8 Ma) show over−dispersed or random morphospace occupation because of a depleted fauna, precluding successive structural changes. The same applies for the extant European carnivore guild as a result of recent extinctions without replacement.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies