Oral Surg Oral Med Oral Pathol Oral Radiol Endod
February 2008
Objective: A new technique for producing splints for orthognathic surgery using a 3D printer is presented.
Study Design: After 3-dimensional (3D) data acquisition by computerized tomography (CT) or cone-beam computerized tomography (CBCT) from patients with orthognathic deformations, it is possible to perform virtual repositioning of the jaws. To reduce artifacts, plaster models were scanned either simultaneously with the patient during the 3D data acquisition or separately using a surface scanner.
During the development of the central nervous system (CNS), the correct wiring of outgrowing neurites is mediated by antagonistic mechanisms. Aberrant growth is prevented by repulsive factors such as semaphorins. Expression of the ligands Sema3A and -3E and the receptors neuropilin Npn-1, -2a and -2b in the chick visual system were analyzed by RT-PCR.
View Article and Find Full Text PDFNeuroembryogenesis critically depends on signaling molecules that modulate cell proliferation, differentiation, and the formation of neural networks. In an attempt to identify potential morphogenetic active components that are distributed in a graded fashion in the developing nervous system, we generated substraction libraries of the embryonic nasal and temporal chick retina. Selected clones were analyzed by sequencing, Northern and Western blotting, in situ hybridization, and immunocytochemistry.
View Article and Find Full Text PDFDesign of attachment devices in insects varies enormously in relation to different functional loads. Many systems, located on different parts of the body, involve surfaces with particular frictional properties. Such systems evolved to attach parts of the body to each other, or to attach an insect to the substratum by providing fast and reversible attachment/detachment.
View Article and Find Full Text PDFThis paper studies slide-resisting forces generated by claws in the free-walking beetle Pachnoda marginata (Coleoptera, Scarabaeoidea) with emphasis on the relationship between the dimension of the claw tip and the substrate texture. To evaluate the force range by which the claw can interact with a substrate, forces generated by the freely moving legs were measured using a load cell force transducer. To obtain information about material properties of the claw, its mechanical strength was tested in a fracture experiment, and the internal structure of the fractured claw material was studied by scanning electron microscopy.
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