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《Dental materials》2020,36(1):119-134
ObjectiveThe aim of this systematic review and meta-analysis was to evaluate the effect of surface conditioning methods on the bond strength of industrial indirect composite blocks (ICs).MethodsBased on the PICOS strategy, the Medline via PubMed, Embase and Web of Science (ISI – Web of Knowledge) electronic databases were searched for peer-reviewed articles in both English and Chinese, with no publication year limit. In vitro studies evaluating the effects of surface conditioning on the bond strength of ICs were selected. The meta-analysis was conducted to calculate the mean difference between surface-conditioned ICs and unconditioned controls. Subgroup analysis was performed to evaluate the different surface conditioning methods, separately for polymer-infiltrated ceramic network (PICN) material and the ICs with dispersed fillers (ICDFs). Meta-analyses were performed with a random-effects model at a significance level of 0.05.Results and SignificanceFrom 802 relevant studies, 25 were selected for full-text analysis. Nineteen studies were eligible for inclusion in this systematic review, whereas 9 studies were included in the meta-analysis. A manual search of the principal periodicals specific to the area resulted in no additional articles. The meta-analysis indicated a significant difference in bond strength between the surface-conditioned ICs and controls under both non-aged and aged conditions. The combination of mechanical and chemical conditioning yielded the highest bond strength of ICs. This meta-analysis suggests that chemical etching followed by a universal primer and alumina air abrasion followed by a silane coupling agent could be considered the best strategy for optimizing the bond strength of PICN materials and ICDFs under aged conditions, respectively. 相似文献
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大孔吸附树脂分离纯化何首乌有效成分二苯乙烯苷的研究 总被引:2,自引:0,他引:2
目的研究不同型号大孔吸附树脂纯化何首乌中二苯乙烯苷的工艺条件及参数。方法以静态饱和吸附量、洗脱量、静态洗脱率为考察指标,比较了7种大孔树脂,并对HPD500树脂的动态比上柱量、比吸附量、比洗脱量进行了考察,以二苯乙烯苷转移率和纯度为指标对树脂吸附工艺条件进行了筛选。结果所比较的7种树脂中,HPD500型树脂具有最佳的吸附及洗脱参数,其动态饱和吸附量达到151.7mg·g-1干树脂,其最佳工艺为以6倍柱体积去离子水、4倍柱体积10%乙醇、6倍柱体积60%乙醇依次洗脱,二苯乙烯苷转移率为95%,其纯度为75.3%。结论HPD500树脂吸附性能较好,适合于何首乌中二苯乙烯苷的纯化。 相似文献
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目的:制备银杏内酯B(GB)柔性纳米脂质体,并对其体外透皮规律进行研究。方法:采用薄膜分散法制备银杏内酯B柔性纳米脂质体,并对其形态及粒径大小进行分析;采用改良的 Franz 扩散池进行体外透皮吸收试验,比较银杏内酯B醇溶液、银杏内酯B柔性纳米脂质体及普通银杏内酯B纳米脂质体的经皮累积渗透量及渗透速率。结果:此方法制得的脂质体平均包封率为(89.52±1.76)%,平均粒径为(208.3±25.49) nm,Zata电位为-49.2 mV。柔性纳米脂质体8 h的累积透过量为189.97 μg·cm-2,8 h的渗透速率为23.75 μg·cm-2·h-1。结论:柔性纳米脂质体包封率较高,稳定性良好,可显著促进银杏内酯B的透皮吸收。 相似文献
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Scleroderma is a chronic disease that has been associated with immune dysfunction. One of the oral manifestations is microsomia, a result of collagen deposition in the perioral tissues. The complexity of treating these patients includes limited mouth opening ability, and difficulty inserting and removing dentures due to finger deformity. This article will describe an appliance specially designed especially for scleroderma patients, which facilitates treatment of the patient with removable partial dentures (RPD). 相似文献
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Malodour in denture wearers: an ill-defined problem 总被引:1,自引:1,他引:0
J Verran 《Oral diseases》2005,11(S1):24-28
Denture plaque has not been studied to the same extent as dental plaque, and although there are many similarities in microbial composition, there are some significant differences. Denture-induced stomatitis is associated with poor denture hygiene, a more acidogenic plaque and the presence of Candida albicans . Obligate Gram-negative anaerobic micro-organisms, although present in denture plaque, have rarely been specifically investigated. Opportunist pathogens including coliforms and staphylococci have been isolated from dentures. Teeth adjacent to partial dentures are more susceptible to caries and periodontal diseases, perhaps due to an increased plaque buildup at the prosthesis/tooth interface. Little work has been published on malodour associated with dentures. The inert material provides a substratum for the plaque biofilm, which encompasses a range of odour-producing species. The microbiology of the tongue in denture wearers has not been specifically studied. Thus the nature, origin and extent of malodour in denture wearers is ill-defined, but many species capable of producing malodorous compounds are present. The wide age and health range presented by denture wearers further confounds investigation. There is a need for further work in the area, both for cosmetic- and health-associated reasons in the increasing elderly population. 相似文献