RESUMEN
Discolored teeth can be treated by various techniques, including direct composite resin veneers, indirect porcelain veneers, ceramic crowns and bleaching agents. The aim of this study was to evaluate the effect of at-home and in-office bleaching agents on the surface microhardness of one microhybrid [Point 4] and two nanofilled [Filtek Supreme and Premise] composite resins. Opalescence PF with 20% carbamide peroxide and Opalescence Quick with 35% carbamide peroxide were used as at-home and in-office bleaching agents, respectively. Fifty samples from each composite resin, including Point 4 microhybrid, Premise and Filtek Supreme nanofilled composites resins were prepared and exposed to bleaching agents. For each composite resin the samples were randomly divided into five groups of 10 and designated as: control, two-week at-home, four-week at-home, one-time in-office and two-times in-office bleaching groups with two-week intervals. After the appropriate bleaching procedures on samples of each group, microhardness measurements were carried out on each sample. Data was analyzed using ANOVA and post hoc Tukey HSD test [p value < 0.05]. There were significant differences in mean surface microhardness values of each composite resin type. No significant differences were observed in mean microhardness values of Point 4 between four-week at-home and one-time office, Filtek Supreme between two-week at-home and four-week at-home, and Premise between one-time in-office and two-time in-office bleaching groups. Under the limitations of the present study, it was concluded that the microhardness of three composite resins tested in the present study were affected by bleaching agents
RESUMEN
One of the basic problems of hospital management is lack of an effective fiscal system, which causes in loose cost control. Meanwhile, accounting techniques and economic analyses may help the managers to decide better in planning programs and investing fields. Then, it's time to have a better estimate of health care services costs in our competitive situation for the hospitals, in this case "The Isfahan Al-Zahra Hospital". This study based on the data in the first half of 2006. This was a descriptive retrospective study on different clinical and Para clinical departments of the Isfahan Al-Zahra Training and Medical Services. All direct and indirect costs gathered through fiscal system documents and via direct process observations. Health care costs estimated using cost accounting techniques after fragmenting all accumulated costs over relative cost centers. Data analyzed by Excel software. The mean value of expense were 14.2 $, 0.7 $ and 4.6 $ in general clinical, libratory and radiology departments, respectively the mean value of expense were 2.8, 10.5, 24.5, 9, 2.5, and 5.8 in sonogeraphy, CT scan, MRI, EEG, ECG and rehabilitation departments respectively. Mean of different with the governmental price were 8.2, 0.03, 1, 6.7, 8.7, 22.9, 12, 0.1, and 3.7 $ in clinics, laboratory, radiology, sonogeraphy, CT scan, MRI, EEG, ECG and rehabilitation departments respectively. According to the findings, except for some Para clinic services, others showed a noticeable imbalance between their costs [at the end] and their Tariffs. This- in turn- conducted to an economic imbalance in those departments in the survey period