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Biomedical subjects

B Kerebel

Publications and source records attributed to B Kerebel.

At least 91 records · Page 5Linked to original sources
PubMed1975

[Action of calcitonin in experimental periodontolysis in the golden hamster].

48 male goldern hamsters 5 weeks old were divided in 4 groups. The first group was used as control. The second was submitted to the 2 000 cariogenic Keyes diet inducing severe alveolar bone resorption. The third and fourth group received with the same diet a thyrocalcitonin injection every two days (3rd group) and every day (4th group) during three months. The study of the alveolar plates with the scanning electron microscope in the animal having received thyrocalcitonin showed a reduced number of resorption lacunae, a denser bone surface covered by a homogeneous and dense granular material similar to that observed in the controls. The calcified globules, constituting the bone anchoring of the Sharpey's fibres, were different from those of the second group submitted to Keyes diet and similar to the controls.

Alveolar Process↗
PubMed1975

[Electron microscope study of bacteria in dental plaques following the application of fluorides (author's transl)].

Gels containing fluorides can have profound effects on dental plaques. These gels contain 2% fluorides in the form of sodium monofluorophosphate and sodium fluoride and are buffered to pH 6.5 when applied to teeth they: - encourage the disappearance of certain bacteria, - inhibit the division of cells and diminish their storage of glycogen, - cause a thickening of the bacterial cell wall, - lead to modifications of the bacterial cell membrane, - precipitate the degeneration of most forms of bacteria, - cause the rapid mineralisation of many bacteria. These widespread effects, and the wholesale degeneration of microbial forms, are a reflection of a major breakdown in bacterial metabolism, and provide a partial explanation for the role of fluorides in the prevention of dental caries, and are in accord with previous biochemical and microbial observations.

Adolescent↗
PubMedDate not supplied

[Ultrastructural study of bacterial plaques from caries-free human subjects (author's transl)].

Bacterial plaques from the teeth of individuals without caries were prepared for examination under the electron microscope (Ryter and Kellenberger's fixation). Microbial polymorphism within bacterial plaques has previously been usually studied in relation to the age of the plaque. Actually, the presence of polymorphous micro-organisms and variations in microbial density observed in 48 hours old plaques, must be related to other factors. Micro-organisms of the same type, as well as bacteria of different types which adhere together, reveal symbiosis and a competition process within the bacterial plaque, thus leading to changes in metabolism and lysis of many of the bacteria. Disturbances in bacterial cell walls; septal vesicular formation and intracellular structures are observed. Bacteriophages found in the plaques may be the cause of lysis of bacteria. Disturbances in bacterial metabolism could explain the lack of carcinogenicity of micro-organisms, and bacterial antigenic complexes which induce probably useful immunological reactions in the host are revealed by the lack of dental caries.

Adolescent↗
PubMedDate not supplied

[A rare dental abnormality: "the phantom tooth" or "odontodysplasia". Apropos of a case].

"Phantom tooth" or "odontodysplasia" is one of the most unusual and rare of dental abnormalities, being characterised: Clinically, by the topography of the lesions, the involvement of both sets of teeth and abnormalities in the size and form of the teeth which remain unrupted or only partially evolved. Radiologically, by transparency of the teeth to X-rays. Histologically, by disorganisation of the dental structures and a highly characteristic appearance of the enamel and, in particular, dentine. On the basis of one case, the authors review in detail each aspect of these characteristics, paying special attention to histology and the information obtained using the sweep electron microscope.

Amelogenesis Imperfecta↗
PubMedDate not supplied

[Ultrastructural odontological study of a case of Papillon-Lefèvre disease].

An ultrastructural study of the teeth and alveolar bone was carried out in a case of Papillon-Lefevre disease, using sweep electron microscopy. There were structural abnormalities of the enamel, numerous zones of cement resorption, the absence of mineralisation of the parodontal fibres inserted in the cement. Osteogenesis was disturbed and the lamina dura showed a granular pattern without any defined orientation.

Alveolar Process↗