Objective:To compare the shear bond strength of dentin to composite resin in different post-treatment time period after tooth bleaching with the TREE dental whitening gel and observe the dentin/composite interface of each group. Methods:Eighteen intact premolars were randomly divided into 3 groups(n=6):A:The specimens were immersed into artificial saliva for 3 weeks then adhesion without bleaching; B:Adhesion immediately after bleaching for 3 weeks,during bleaching the specimens were immersed into artificial saliva; C:Before adhesion the specimens immersed in artificial saliva for further 2 weeks after bleaching for 3 weeks. Five specimens from each group were randomly submitted to shear bond strength test. The specimen remained in each group were sectioned to be observed by the scanning electron microscope.Results:(1)The shear bond strength of the group B (10.74?3.03) MPa was significantly lower than that of the group A (18.61?3.56) MPa or the group C (17.21?3.15) MPa (P0.05); (2)The resin tags present in the dentin/composite interface was scarce for the group B,and that were shorter than the group A; The resin tags of the group A and group C were similar in number,but that of the group C was shorter than that of the group A. Conclusion:The use of TREE whitening gel immediately before bonding significantly reduces bond strength,but immersion of bleached teeth in artificial saliva for 2 weeks before bonding results in a return to control bond strength.

Pi.Au-Pt alloy does not resist the growth and adhesion of the bacteria, but Au-Pd does.

Objective:To assess the influence of different surface treatment on the adhesion of the zirconia-veneering ceramic systems.Methods:28 zirconia specimens were divided into 4 groups(n =7) and treated by non-treatment(group A,the control),sandblaste(group B),hot-etching(group C) and sandblaste + hot-etching(group D).2 specimens randomly selected from each group were examined under SEM and XRD for the observation of surface structure.The veneering porcelain was layered on the remaining specimens of the 4 groups (n =5),then the shear strength of the interface was tested by a universal testing machine.Data were statistically analyzed by SPSS 13.0 software.Results:Different degrees of micro pore structure was observed on the zircomia surface of the 4 groups by SEM observation.The XRD analysis showed that all specimens emerged monoclinic phase.The shear bond strength of group A,B,C and D was (15.96 ± 3.44) MPa,(20.58 ± 2.21) MPa,(26.28 4-2.86) MPa and (22.51 ± 1.94) MPa respectively.group A vs group B,C and D,P ＜ 0.05;group C vs group A,B and D,P ＜ 0.05.Conclusion:The surface treatment of sandblaste,hot-etching and sandblasted + hot-etching can improve the shear bond strength of the zirconia-veneering ceramic systems,and the hotetching method is the most effective.

Objective:To explore the effect of self-management capability cluster intervention on clinical compliance and treatment outcome in patients with end-stage renal disease undergoing hemodialysis.Methods:A total of 88 patients undergoing hemodialysis in dialysis center from June to December 2019 were randomly divided into intervention group (44 cases) and control group (40 cases) according to odd-even number method. Patients in both groups were treated with hemodialysis and basic treatment, and patients in intervention group were treated with self-management capability cluster intervention. The self-management ability, dialysis compliance and related complications were compared between the two groups before and after intervention. The data were statistically analyzed by SPSS 26.0 software. Independent sample t-test was used for intergroup comparison, and paired t-test was used for intragroup comparison. Results:There was no significant difference in self-management ability at baseline between intervention group and control group ( P>0.05). After 6 months, the total score of self-management ability ((68.61±10.16), (55.12±9.29)) and emotional processing ((13.42±2.89), (11.04±2.46)), executive self-care ((21.67±4.87), (16.71±3.59)), problem solving ((16.61±3.22), (12.03±4.61)), partnership ((14.26±3.64), (10.88±3.29)) were higher than those in the control group, and the differences were statistically significant ( t=7.112, 3.764, 4.739, 5.515, 5.834, all P<0.05). The total score of self-management behavior and the scores of four dimensions in the intervention group were significantly higher than those in the control group ( t=13.413, 5.432, 8.114, 1.910, 4.127, all P<0.05). There were significant differences between the intervention group and the control group in jumping behavior (9.09%, 22.50%) , shortening behavior (11.36%, 30.00%) , hyperkalemia (15.91%, 55.00%), heart failure (11.36%, 37.50%) and arteriovenous fistula occlusion (4.55%, 10.00%) ( χ2=4.095, 5.206, 17.571, 8.843, 5.127, all P<0.05). There were significant differences between the intervention group and the control group in urea clearance index, anemia improvement, blood phosphorus, parathyroid hormone level ( t=3.830, 4.558, -3.720, 6.481, all P<0.05). Conclusion:Self-management capability cluster intervention can improve the clinical compliance and treatment outcome in patients with end-stage renal disease undergoing hemodialysis.