الفهرس | Only 14 pages are availabe for public view |
Abstract ا This study was conducted to compare the effect of three remineralizing agents on microhardness of bleached enamel. In total, 85 bovine specimens were randomly assigned into 15 groups (n=5) according to two levels of investigation in this study. Level 1: type of remineralizing agent, level 2: time interval. In addition, two control groups for ground and bleached enamel were used for comparison. After preparation of bovine teeth, Opalescence PF 20% bleaching gel was applied and rinsed according to manufacturer instructions to all specimens except ground enamel group (positive control). Specimens were subjected to three different remineralizing agents CPP-ACPF (MI Paste Plus®), Hydroxyapatite based cream (Remin Pro) and ƒTCP (Clinpro White Varnish™) for different time intervals two, five, seven, fifteen and thirty days. Microhardness of all specimens was measured using Vicker’s microhardness tester. Microhardness of specimens was compared with the microhardness of ground and bleached enamel groups. A representative specimen from each group was randomly assigned to be evaluated under environmental scanning electron microscope. Mean and standard deviation for microhardness of all specimens was calculated. Two-way ANOVA revealed that remineralizing agents and time intervals had significant effect on microhardness of bleached enamel. Difference in type of remineralizing agents showed significant effect on bleached enamel microhardness. ƒTCP (Clinpro White Varnishä) showed the highest significant effect on microhardness followed by Remin Pro then CPP-ACPF (MI Paste Plusâ). Different time intervals also showed statistically significant effect on microhardness of bleached enamel. Fifteen and thirty days were statistically significantly higher compared to two, five and seven days. Remin Pro demonstrated comparable results to ƒTCP (Clinpro White Varnishä) at two, five and seven days, but performed less at fifteen and thirty days. Also, ACPF (MI Paste Plusâ) performed the least at two, five and seven days, and achieved comparable results to both ƒTCP (Clinpro White Varnishä) and Remin Pro in fifteen and thirty days. |