scholarly journals The Relationship of Trauma from Occlusion with Chronic Periodontitis Based on the Quality and Quantity of Alveolar Bone in the Radiographic Features

Author(s):  
Dharshini Neelamegan ◽  
Rini Octavia Nasution
2003 ◽  
Vol 30 (5) ◽  
pp. 394-402 ◽  
Author(s):  
M.V. Vettore ◽  
A.T.T. Leão ◽  
A.M. Monteiro da Silva ◽  
R.S. Quintanilha ◽  
G.A. Lamarca

2020 ◽  
Vol 18 (3) ◽  
pp. 15-25
Author(s):  
A. B. Mallaeva ◽  
N. S. Drobysheva

Aim. To assess the size of the alveolar ridge / part of the jaws in patients with gnathic mesial occlusion of the dentition.Materials and methods. A study was carried out, during which we determined the structural features of the alveolar ridge of the upper and lower jaws of 50 adult patients (from 18 to 44 years old), and also studied the presence / absence of the relationship of this parameter with the inclination of the teeth.Results. The smallest thickness of the alveolar bone in the upper jaw was observed in the area of the mesio-buccal root of the first molars and in the area of the first premolars and canines. The smallest thickness of the alveolar bone in the lower jaw was observed in the area of the vestibular surface of the first and second premolars, canines and incisors. The greatest thickness of the alveolar bone is observed in the distal-buccal region of the second molars.Conclusions. A natural mechanism promotes dentoalveolar compensation, while maintaining the amount of bone in the region of the vestibular and lingual alveolar bones to maintain the integrity of the periodontium.


1988 ◽  
Vol 59 (2) ◽  
pp. 73-79 ◽  
Author(s):  
Paul J. Heins ◽  
Ronald G. Thomas ◽  
Janetta W. Newton

Author(s):  
K. E. Krizan ◽  
D. H. Han ◽  
R. L. Ettinger ◽  
G. F. Koorbusch ◽  
J. D. Spivey

In recent years oral endosteal implants have been placed in healed extraction sites but it has been suggested that osseointegration may not occur. This study places IMZ implants1 in fresh extraction sites with and without two biological graft materials: porous hydroxyapatite granules (HA) and polytetrafluorethylene (PTFE) membranes. The purpose of this study was to investigate the influence of immediate placement of implants on osseointegration. This presentation uses the scanning electron microscope (SEM) to evaluate the relationship of implant to bone. In addition, the effect of these two graft materials on bone regeneration and prevention of soft tissue (ST) ingrowth was examined. Under anesthesia three adult mongrel dogs had premolars extracted bilaterally from the mandible. Using the IMZ system six implant sites were prepared, five implants placed in alveolar bone and the sixth site was a no implant control. A total of fifteen implants were placed in the area between the canine and first molar of the three animals.


Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


Author(s):  
Leon Dmochowski

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.


Author(s):  
J.R. Pfeiffer ◽  
J.C. Seagrave ◽  
C. Wofsy ◽  
J.M. Oliver

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.


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