Estrogen deficiency and chronic alcohol consumption may have a synergistic and deleterious effect on bone tissue. AIM: To investigate the effects of estrogen deficiency associated with chronic alcohol consumption on the mandibular condyle in rats. METHODS: Fifty-four female rats were first divided equally into two groups: ovariectomized Ovx and simulated ovariectomy Sham. One month after the surgeries, these groups were equally sub-divided according to their dietary treatment: G1: Sham/ad-libitum diet; G2: Sham/alcohol; G3: Sham/isocaloric; G4: Ovx/ad-libitum diet; G5: Ovx/alcohol, G6: Ovx/isocaloric. Eight weeks after starting the diets, all animals were anesthetized and sacrificed. The condyles were analyzed histologically, histomorphometrically, and immunohistochemically using the antibodies for bone sialoprotein BSP, osteocalcin OCC and receptor activator of nuclear factor kappa-B ligand RANKL. RESULTS: Histological analysis of the mandibular condyles showed that Ovx and Sham groups presented almost the same characteristics. The histomorphometric analysis showed that there was a statistically significant difference only between Ovx/isocaloric and Ovx/ad-libitum groups p=0.049. No difference was observed in the intensity of BSP, OCC, and RANKL antibody staining between the Ovx/alcohol and the other groups. CONCLUSIONS: It may be concluded that there was no histomorphometric, histological, or RANKL, BSP, and OCC staining differences between the Ovx/alcohol group and other experimental groups.

Objective The aim of this paper was to evaluate the repair of onlay autogenous bone grafts covered or not covered by an expanded polytetrafluoroethylene (e-PTFE) membrane using immunohistochemistry in rats with induced estrogen deficiency. Material and Methods Eighty female rats were randomly divided into two groups: ovariectomized (OVX) and with a simulation of the surgical procedure (SHAM). Each of these groups was again divided into groups with either placement of an autogenous bone graft alone (BG) or an autogenous bone graft associated with an e-PTFE membrane (BGM). Animals were euthanized on days 0, 7, 21, 45, and 60. The specimens were subjected to immunohistochemistry for bone sialoprotein (BSP), osteonectin (ONC), and osteocalcin (OCC). Results All groups (OVX+BG, OVX+BMG, SHAM+BG, and SHAM+BMG) showed greater bone formation, observed between 7 and 21 days, when BSP and ONC staining were more intense. At the 45-day, the bone graft showed direct bonding to the recipient bed in all specimens. The ONC and OCC showed more expressed in granulation tissue, in the membrane groups, independently of estrogen deficiency. Conclusions The expression of bone forming markers was not negatively influenced by estrogen deficiency. However, the markers could be influenced by the presence of the e-PTFE membrane.

The aim of this study was to evaluate the resorption process during the repair of autogenous bone grafts with or without coverage by an expanded polytetrafluoroethylene (e-PTFE) membrane in female rats with estrogen deficiency using the immunohistochemical technique. Eighty female rats were randomly divided into two groups (OVX and SHAM). The 40 female rats in the OVX group were subjected to ovariectomy, and the 40 female rats in the SHAM group were subjected to simulated ovariectomy. The two groups were further divided in subgroup E, which was subjected to surgery for placement of autogenous bone graft (ABG), and subgroup ME, in which the ABG was covered with an e-PTFE membrane. The animals were killed at 0, 7, 21, 45 and 60 days. The specimens were analyzed using immunohistochemistry for the bone resorption markers RANK, RANK-L and Osteoprotegerin (OPG). A higher remodeling rate was observed at 7 and 21 days after the autogenous bone grafts, when the markers were more intensely expressed. At the final time point, the specimens presented similar characteristics to those observed at the initial time point. The expression of immunohistochemical markers was not altered by the estrogen deficiency. The presence of the e-PTFE membrane delayed the bone resorption process, influencing the immunohistochemical expression of markers.