Sökning: "natural teeth"

Visar resultat 1 - 5 av 38 avhandlingar innehållade orden natural teeth.

  1. 1. Early Campanian mosasaurs (Reptilia; Mosasauridae) from the Kristianstad Basin, southern Sweden

    Författare :Johan Lindgren; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sedimentologi; Sedimentology; vertebrae; Tylosaurus; teeth; Sweden; Mosasauridae; Kristianstad; Halisaurus; Clidastes; Hainosaurus;

    Sammanfattning : Marine strata of latest early Campanian age (sensu germanico) in the Kristianstad Basin, Skåne (Scania), southern Sweden, have yielded a diverse mosasaur fauna comprising six to eight taxa, including Tylosaurus ivoensis, Clidastes propython, Hainosaurus minor n. sp., Halisaurus sternbergii, Platecarpus cf. somenensis, Platecarpus? sp. LÄS MER

  3. 2. 100 million years of shark macroevolution : A morphometric dive into tooth shape diversity

    Författare :Mohamad Bazzi; Per Ahlberg; Matt Friedman; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sharks; Macroevolution; Extinction recovery dynamics; Geometric Morphometrics; Morphospace-Disparity Framework; Teeth; Biology with specialization in Evolutionary Organismal Biology; Biologi med inriktning mot evolutionär organismbiologi;

    Sammanfattning : Few vertebrate clades exhibit the evolutionary longevity and versatility of sharks, which constitute nearly half of all current chondrichthyan biodiversity and represent an ecological diversity of mid-to-apex trophic-level predators in both marine and freshwater environments. The rich fossil record of shark teeth from Mesozoic and Cenozoic rocks also makes the group amenable to large-scale quantitative analyses. LÄS MER

  4. 3. Sensor-based navigating mobile robots for people with disabilities

    Författare :Håkan Neveryd; Certec - Rehabiliteringsteknik och Design; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Rörelsehinder; Robotar;

    Sammanfattning : People with severe physical disabilities need help with everyday tasks, such as getting dressed, eating, brushing their teeth, scratching themselves, drinking, etc. They also need support to be able to work. They are usually helped by one or more personal.. LÄS MER

  5. 4. The Origin of Tooth Replacement : Three-dimensional Synchrotron Histology Visualizes the Dental Development of Silurian Stem Osteichthyans

    Författare :Donglei Chen; Per Ahlberg; Zerina Johanson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Mechanisms of tooth replacement distribute incongruently among extant gnathostomes (jawed vertebrates): a permanent tooth-generating dental lamina exists in chondrichthyans (cartilaginous fish) and tetrapods but not teleosts, whereas tooth shedding by basal hard tissue resorption occurs in tetrapods and teleosts but not chondrichthyans. Theories about the evolution of tooth development have been biased towards the chondrichthyan conveyor-belt replacement, since there has been no fossil evidence for the origin of osteichthyan (bony fish and tetrapods) tooth replacement until now. LÄS MER

  7. 5. Characterising Dental Implant Surfaces by Topographical, Electrochemical, and Biomechanical Methods

    Författare :Johanna Löberg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Titanium dental implants; 3D-SEM; AFM; Mott-Schottky analysis; surface roughness parameters; biomechanics.;

    Sammanfattning : Replacement of extracted teeth by dental implants was first introduced in the 1950’s. From the beginning, threaded titanium implants with smooth surfaces were used. Later on, screw shaped implants with micro-scaled roughened surfaces were introduced showing bone ingrowth and improved in vivo and in vitro results and good long term stability. LÄS MER