[Evaluation of the effect of pre- and post-topical fluoride treatment on marginal microleakage of resin composite and glass ionomer restorations]

Fluoride has popularly been used as a caries prevention agent. This study evaluates the effect of fluoride gel [APF] on microleakage before and after restoration placement of tooth colored restorations. Eighty-four standard class V cavities were prepared and the specimens were randomly divided into three groups [n=14]: Group 1-APF employed before cavity preparation; Group2-APF employed after completed restoration: Group3- without APF application [control]. Buccal cavities were restored with OptiBond Solo adhesive system and Herculite XRV composite resin and lingual cavities were restored with Fuji II LC Glass ionomer. After finishing and polishing, thermal cycling followed by immersion in 0.5% basic fuchsin dye was performed. Then, the specimens were sectioned and microleakage was ranked under magnification [x40]. Two teeth of each group were treated for SEM observation. Data were subjected to statistical analysis using Kruskal Wallis and Wilcoxon tests. There were significant differences in enamel marginal microleakage of composite [14.68] and glass ionomer [16.00] restorations [p=0.02], but they similarly proceeded in dentinal margins [0.921]. The dentinal margins [2.50] of the glass ionomer in control group showed more leakage than the enamel margins [0.00] [p=0.04]. All experimental groups; either before or after fluoride therapy, showed similar microleakage in the enamel and dentinal margins. APF employed was ineffective on microleakage before and after composite resin restoration placement. Microleakage could increase in enamel margins of resin modified glass ionomer restoration with fluoride therapy protocol

[Effect of combined administration of estrogen and progesterone on brain edema and neurological outcome after traumatic brain injury in female rats]

Many studies have shown uncontrolled brain edema to be the cause of disabilities and deaths following head trauma. Current data also suggests that a single administration of estrogen or progesterone can have neuroprotective effects on brain injury. In this study we investigated the combined effect of estrogen and progesterone on brain edema and neurological outcomes following traumatic brain injury [TBI] in female rats This interventional-experimental study was performed on 8 groups of female rats as follows: 1- control, 2-Sham, 3-Ovarectomized trauma [TBI+OVX] 4-Vehicle 5-Physiologic dose of estrogen + physiologic dose of progesterone [E1+P1], 6- physiologic dose of estrogen+pharmacologic dose of progesterone [E1+P2] 7-Pharmacologic dose of estrogen+physiologic dose of progesterone [E2+P1] and 8-Pharmacologic dose of estrogen+pharmacologic dose of progesterone [E2+P2]. Hormones were injected i.p, half an hour after diffuse traumatic brain injury through marmarou model to 2 week old ovarectomized rats. Brain edema [via brain water content], blood-brain barrier permeability [via extra vascular evans blue dye] and neurological outcome [via veterinary coma scale] were measured in this animals The results showed significance decreases of 2.68% and 2.88% in water content in group 8 compared to the vehicle group and group 6 respectively and a significant decrease of 2.29% in water content in group 5 compared to group 6. Evans blue level showed significant decreases of 14.7% and 21.1% in groups 6 and 7 compared to the vehicle group. Neurological scores showed a significant increase of 2.5 and 2 in group 5 compared to the vehicle group and group 3, 1 hour after TBI respectively a significant increase was seen in all groups compared to group 3 at 4 and 24 hours after TBI. Scores showed a significant increase of 1.2 in groups 7 and 8 compared to the vehicle group at 24 hours following the TBI. Based on these results, it can be concluded that combined administration of estrogen and progesterone have beneficial effects on both the reduction of brain edema and the neurological outcomes, the improvement depending on what dose of estrogen is administered with progesterone