الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
- 210 children with mean age of years were selected. Class II composite restorations of the lower second primary molars were bonded with either Prime & Bond NT or Single Bond adhesive under normal or saliva / blood contaminated conditions and evaluated at 3, 6, 9,and 12 months.Patients were divided into 2 main groups according to the used adhesive. Then each group was subdivided into 7 subgroups. (1) no contamination. (2) saliva after acid etching, (3) saliva after adhesives curing, saliva removed by air, adhesives reapplied , (4) as (3) except that saliva was removed with disposable brush. (5) blood after etching, rinsed with water. (6) blood after adhesives curing, blood removed by air, adhesives were re-applied. Subgroups (7) as subgroups (6) except that blood was removed with disposable brush between the 2 layers of cured adhesives.Clinical examination and photographs were recorded at each recall visit; teeth were replicated for scanning electron microscope analysis of marginal gap. Laboratory study: 280 sound primary molars were divided into 2 main groups according to the used adhesive. Group was subdivided into 7 subgroups as in the clinical study. Flat enamel and dentin surfaces on the buccal and lingual surfaces of the same teeth were established for bonding. After adhesive application, plastic mold was filled with composite, applied to the bonding surface and light cured. Shear bond strength was measured using Instron testing machine. Specimens were examined under stereomicroscope and selective samples were examined with scanning electron microscope to determine the mode of failures. Statistical analysis of the results of the clinical study showed that, saliva contamination had no negative effect on the clinical performance of the two adhesives, while blood contamination compromised the clinical performance especially when it occurred after adhesive curing.