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1.
随着对龋病病因及发病机制的深入认识,龋病的治疗不应局限于对现有龋损的修复治疗,而应以龋病风险评估和龋损活跃性评估为基础,以患者为中心,制定个性化的治疗方案,恢复口腔微生态平衡,进而控制龋病进展和恢复患牙的结构与功能。 相似文献
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Optical fluorescence imaging methods have a range of forensic applications. The VistaCam system (Dürr Dental) is an existing intra-oral fluorescence camera, which was designed to aid detection of dental caries using 405 nm wavelength light generated by light emitting diodes (LEDs). This study assessed whether this fluorescence imaging device could also be used to recognize dental restorative materials, which is essential for accurate dental charting of deceased persons who are unidentified. The effect of body fluids (saliva and blood) on performance was also assessed. The VistaCam was used on the bench to assess 55 extracted human teeth with restorations, and samples of restorative materials. Readings were first taken in the moist state and then after the application of human saliva or venous blood. Fluorescence scores were compared using one-way ANOVA. Human enamel gave lower fluorescence than restorations. Different tooth-coloured restorative materials gave similar strong fluorescence scores, without statistically significant differences between them. Fluorescence scores were not affected by the presence of ambient fluids (saliva or blood). Using violet 405 nm light to elicit fluorescence may aid in the recognition of dental restorative materials. 相似文献
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中药材专业市场交易量逐渐下降,产地市场交易成为趋势。研究产地市场整合程度有利于了解中药材市场的运行情况,对于合理规划中药材生产和提高市场效率具有重要意义。选取大宗中药材金银花、枸杞子、板蓝根和太子参研究中药材市场整合程度,利用2013—2019年价格指数,运用协整检验、误差修正模型和格兰杰因果检验进行实证分析。结果表明,我国中药材产地市场长期整合程度较高;中药材产地市场的短期整合程度远不及长期整合程度。为此提出4点政策建议:完善中药材价格信息平台、打造非道地产区中药材优质品牌、加快建成中药材质量追溯体系和建设中药材现代物流体系。 相似文献
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《Journal of endodontics》2020,46(11):1766-1770
IntroductionThe aim of this study was to evaluate the effect of different access opening restorative materials on crown retention.MethodsThirty-eight extracted molars were mounted in resin and prepared for porcelain fused to metal (PFM) crowns. The crowns were fabricated and cemented with zinc phosphate, and the force to displace it was measured with a tensile-testing machine before and after endodontic access preparations. The endodontic access area, crown preparation axial wall, and preparation surface area were measured for comparison. The crowns were then recemented, and access openings were restored with either amalgam or composite before displacement force was remeasured. The restorative material was removed from each access opening; access area was measured and restored again (amalgam with composite or fiber post with composite) for displacement force to be remeasured. Paired t test was used to compare the means of displacement between groups. One-way analysis of variance was used to compare the mean outcome measure within the groups.ResultsStatistical analyses showed retention after unfilled access was significantly lower than intact crowns. Amalgam, composite, amalgam + composite, and fiber post + composite increased retention beyond the original value. There was no statistical difference among the different restorative protocols. Qualitative results indicate that the restorative material remains in the crown after displacement regardless of the material used to restore the access.ConclusionsThe results from this study suggest that an endodontic access cavity decreases retention of a PFM crown. However, subsequent restoration with amalgam, composite, amalgam + composite, or post + composite may increase the original retention of the crown. 相似文献
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《Japanese Dental Science Review》2020,56(1):184-189
The purpose of the present review was to survey the available literature on computer-aided design/computer-aided manufacturing (CAD/CAM)-produced resin composite materials to provide clinicians with a current overview of the key components necessary for daily clinical use. An electronic search was conducted in the PubMed database. Peer-reviewed articles in English language on the use of resin composites in CAD/CAM dental crowns were included. A total of 122 full-text articles were identified, 15 of which were selected during the initial review. Two additional articles were also discovered through a manual search, to obtain a final total of 17 articles included in the present review. Of these, 16 were to in vitro studies, and one was an in vivo study. Findings from the in vitro studies indicate that resin composite block materials for CAD/CAM applications demonstrate excellent physical properties and are appropriate for the clinical restoration of premolars and molars. However, the in vivo study reported a low 3-year success rate, but high survival rate for resin composite CAD/CAM crowns placed in the premolar region. The key to ensuring the successful prognosis of a resin composite CAD/CAM crown is to ensure that all steps—such as proper case selection, abutment tooth preparation, occlusal adjustment, and bonding—are accurately performed. 相似文献
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《International journal of oral and maxillofacial surgery》2020,49(6):797-810
In this systematic review and network meta-analysis including only randomized clinical trials (RCTs), different grafting materials used in alveolar ridge preservation after tooth extraction were analysed, focusing on histomorphometric new bone formation (NBF) in core biopsies obtained during implant placement. The PubMed, Embase, Cochrane Library, Web of Science, Scopus, and LILACS databases, as well as the grey literature, were searched for published and unpublished trials (from database inception to January 14, 2019). The primary outcome was the percentage of NBF. The secondary outcomes were the percentage of residual biomaterial and the percentage of soft tissue. An arm-based network meta-analysis was performed. The rank of intervention efficacy was obtained to measure the probability of each biomaterial being ranked first across all interventions. A total of 1526 studies were found, of which 38 were included for quantitative analysis. Three trials were rated as having a high risk of bias and 35 trials as having an unclear risk of bias. The network meta-analysis showed that nine grafting materials decreased NBF and 25 did not decrease NBF. The grafting material with the highest amount of NBF was plasma rich in growth factors. Due to the lack of studies with a low risk of bias, further RCTs are needed for definitive conclusions. 相似文献
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目的建立保健食品原料评价体系(Functional Food Crude Materials Evaluation System,FUFMES),为保健食品原料目录排名提供科学依据与技术保障。方法首先,利用文献调研和多轮专家访谈方法筛选FUFMES的指标并确定其层级关系;第二,使用层次分析法(Analytic Hierarchy Process,AHP)计算指标权重,具体方法是依据专家打分构建判断矩阵,利用R语言进行一致性检验与最大特征根检验,得出各级指标权重;第三,使用极值法计算原料的单个指标值;第四,利用线性加权综合法得到每种原料的评价指数并据此进行排名;最后,将获得的分析结果与专家评价结果进行比较。结果 FUFMES包括6个一级指标、39个二级指标、11个三级指标。利用FUFMES对9种保健食品原料进行评价,获得的评价指数依次是:西洋参(0.49)、人参(0.48)、银杏叶(0.21)、灵芝孢子粉(0.08)、鱼油(0.06)、螺旋藻(0.03)、辅酶Q10(0.02)、褪黑素(0.01)、大蒜油(-0.03)。基于该评价指数的排名结果与专家评价结果显示了较高一致性。结论构建了科学、完整的FUFMES,FUFMES将成为保健食品原料目录评价与排名的有力工具,为推进保健食品原料备案制提供科学依据与技术保障。 相似文献
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目的通过检索特殊食品信息查询平台公布的具有缓解视疲劳功能的保健食品信息资料,以及药智数据网的中成药处方数据库中眼科中成药中有保健功能的产品信息资料,为具有缓解视疲劳功能的保健产品的组方与产品开发提供依据与参考。方法运用Microsoft Excel2016软件及中医传承辅助平台对检得的产品信息进行统计,分析其配方特点。结果共收集到141个具有缓解视疲劳功能的保健食品,其中64个(45.4%)保健食品配方中含有中药类原料。使用频次≥5的中药原料有6味,累计使用145次(72%),由高到低分别是菊花、枸杞子、决明子、桑椹、熟地黄、茯苓。通过无监督的熵层次聚类得到3个新处方。非中药原料在缓解视疲劳功能的保健食品中应用较为普遍,含有外来天然植物资源的60个产品,含叶黄素及维生素类的17个。统计眼科中成药中有保健功能的产品可知,使用频次≥4的中药原料有7味,累计使用32次(29%),由高到低分别是枸杞子、决明子、菟丝子、熟地黄、菊花、五味子、车前子。通过无监督的熵层次聚类得到1个新处方。结论保健食品在中药原料的选择上与中医药理论治疗视疲劳的原则基本契合,即滋补肝肾、平肝明目。但二者在中药原料选择范围、原料配伍、剂型种类等方面有所不同。此外,还在辨证保健理论指导下,尝试探讨应用文献数据处理统计方法筛选新配方、开发新产品,为中药复方保健产品的研发开辟了新思路、新方法。 相似文献