الفهرس 
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Abstract
This study was conducted to evaluate some properties of 2 self etching bonding agents; one fluoride releasing designated as FR while the other was non fluoride releasing designated as NFR.
The biological test was the rabbit blood hemolysis test. Adhesives were prepared by curing their drops on a glass slab then addition of 0.5 gram to tubes and covered with saline. Diluted rabbit blood was added and then the tubes were incubated. A positive control was prepared by addition of sodium carbonate to diluted blood and negative control was prepared by addition of saline to diluted blood. After the incubation period the tubes were centrifuged then the supernatant transferred to a spectrophotometric cell and the optical densities were recorded. The blood hemolysis was calculated through special formula.
The mechanical test was the shear bond strength test. Two hundred caries free extracted human molars were collected for this test. They were divided into two groups, enamel group and dentin group with 100 teeth each. Enamel and dentin were flattened. Then each group was sub grouped into two sub groups, 50 teeth each according to the type of adhesive. Each sub group was sub divided into five groups, ten teeth each according to the storage periods. Adhesives were applied and resin composite cylinders and the samples were incubated for the determined storage periods. The samples were tested for shear bond strength with a universal testing machine. Test was conducted till separation of composite cylinder from tooth and stress at failure was calculated.
For dye penetration test 40 anterior teeth were used. The teeth were sub divided into two groups, 20 teeth each according to presence or removal of. Class V cavities were prepared in the cervical one third of teeth in both groups. Each group was sub divided into two groups, 10 teeth each according to type of applied adhesive. After application of adhesive, the cavities were stored with resin composite and stored in 2% toluidine blue dye for 7 days and stored in an incubator. Teeth then were sectioned and examined for dye penetration under stereomicroscope.
For gap evaluation under SEM 40 anterior teeth were prepared the same way as those prepared for dye penetration test. Teeth were stored in distilled water for 7 days in an incubator then teeth were sectioned then they were examined under SEM.
The results for hemolysis test showed that both adhesives were not hemolytic although FR had higher effect than NFR.
The results of shear bond strength revealed that the bond strength of both materials decreased with time and the NFR releasing adhesive had higher bond strength overall periods of storage. The results with revealed that the FR had lower bond strength than NFR.
The dye penetration test revealed that the presence of enamel decreased the marginal leakage and FR showed more dye penetration than the other adhesive with no significant difference. Under SEM the fluoride releasing bonding agent showed higher gap values at the interface with less contact areas than the other adhesive.