PERSONAL DE APOYO
LEWICKI Marianela
congresos y reuniones científicas
Título:
Efecto de la deficiencia de estrógenos sobre los osteocitos del hueso alveolar.
Autor/es:
SÁNCHEZ LM; BOZAL CB; LEWICKI M; UBIOS AM
Lugar:
Mar del Plata, Buenos Aires
Reunión:
Congreso; XL Reunión de la Sociedad Argentina de Investigación Odontológica (SAIO); 2007
Institución organizadora:
SAIO
Resumen:
Deficiency of estrogen during menopause alters the sensitivity of bone to mechanical loading, thereby contributing to bone loss. This phenomenon may be caused by a reduction in the number of living osteocytes or a reduction in osteocyte function. No studies were performed to determine the effect of estrogen deficiency on alveolar osteocytes and their lacunae before and during the installation of the osteopenia. The objective of the present work was to evaluate the histomorfometric changes in osteocytes and its lacunae in alveolar bone of rats subjected to estrogen deficiency by means of ovariectomy, before and during the installation of the osteopenia. We used a rat model of ovariectomy (OVX) to produce the estrogen deficiency. Forty two 9-week-old female Wistar rats were divided into 3 groups: 1) control, 2) sham and 3) OVX. From bibliography the osteopenia in interradicular bone is evident from 60 days of ovariectomy, so that two experimental times were determined: 15 days and 60 days. Blood samples were taken and mandibles were extracted from all animals. The blood levels of estrogen diminished significantly in OVX group at 15 days compared to their controls simultaneously that did not register a diminution in Interradicular bone volume. To 60 days of OVX the estrogen levels stayed significantly lower but the interradicular bone volume diminished compared to controls. The changes found in histomorphometric patterns of osteocytes and their lacunae at the beginning of estrogen deficiency show that osteocytes respond to the systemic stimulii previously to the installation of osteopenia. This shows that in alveolar bone in addition to its well-known mecanoreceptor function, the osteocyte is also sensible to hormonal changes and could act leading the remodeling process in systemic conditions that alter the normal behavior of the bone. Grants UBACyT O 013 and PIP-CONICET 6010Key words: osteocyte, lacunar density, estrogen deficiency, ovariectomy, osteopenia