RESUMEN
Mechanical stimulation contributes to the health of alveolar bone, but no therapy using the osteogenic effects of these stimuli to increase alveolar bone formation has been developed. We propose that the application of high-frequency acceleration to teeth in the absence of significant loading is osteogenic. Sprague-Dawley rats were divided among control, sham, and experimental groups. The experimental group underwent localized accelerations at different frequencies for 5 min/day on the occlusal surface of the maxillary right first molar at a very low magnitude of loading (4 µÎµ). Sham rats received a similar load in the absence of acceleration or frequency. The alveolar bone of the maxilla was evaluated by microcomputed tomography (µCT), histology, fluorescence microscopy, scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR imaging), and RT-PCR for osteogenic genes. Results demonstrate that application of high-frequency acceleration significantly increased alveolar bone formation. These effects were not restricted to the area of application, and loading could be replaced by frequency and acceleration. These studies propose a simple mechanical therapy that may play a significant role in alveolar bone formation and maintenance.
Asunto(s)
Proceso Alveolar/fisiología , Osteogénesis/fisiología , Vibración/uso terapéutico , Aceleración , Animales , Fenómenos Biomecánicos , Densidad Ósea/fisiología , Calcificación Fisiológica/fisiología , Carbonatos/análisis , Colágeno/ultraestructura , Imagenología Tridimensional/métodos , Masculino , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Diente Molar/fisiología , Tercer Molar/fisiología , Oscilometría , Estimulación Física , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectroscopía Infrarroja por Transformada de Fourier , Estrés Mecánico , Microtomografía por Rayos X/métodosRESUMEN
A 70-year-old woman with pemphigus foliaceus is reported. Direct immunofluorescence performed on perilesional skin revealed deposits of IgA, C3 and lambda chains in the intercellular substance of the upper stratum spinosum. Indirect immunofluorescence demonstrated serum antibodies of the IgA class against the intercellular region of the upper epidermis at an initial titre of 1:2560. Histological studies, performed together with immunofluorescence, revealed an absence of a distinct neutrophil infiltrate either in the epidermis or dermis, contrary to the findings in cases with intra-epidermal IgA deposits reported previously.