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1.
氧化锆和纳米金刚石比例对核树脂挠曲强度的影响   总被引:1,自引:0,他引:1  
目的 探讨二氧化锆、纳米金刚石比例对核树脂挠曲强度的影响.方法 采用双酚A-甲基丙烯酸缩水甘油酯(Bis-GMA)和二甲基丙烯酸三甘醇酯(TEGDMA)为树脂基质, 钡玻璃粉(BG)为主填料, 选择不同比例的微米或纳米级二氧化锆,纳米金刚石作为功能填料, 采用原位聚合法生成光固化牙科核树脂,万能材料试验机测定其挠曲强度.结果 含60wt%钡玻璃粉、0.2wt%纳米金刚石的树脂中,加入纳米级或微米级的二氧化锆含量分别为2wt%、3.5wt%、5wt%,3.5wt%相应核树脂挠曲强度最高;含70wt%钡玻璃粉、0.1wt%纳米金刚石的树脂中,加入40 nm的二氧化锆含量为0wt%、2wt%、3.5wt%、5wt%,2wt%质量百分比相应核树脂挠曲强度最高.结论 适当比例填料的核树脂挠曲强度能达到相应的国家标准及ISO标准的规定,能满足临床需要.  相似文献   

2.
纳米增韧牙科复合树脂的研究   总被引:7,自引:0,他引:7  
目的:研究纳米二氧化锆、纳米金刚石为功能填料加入到以钡玻璃粉为主填料的光固化牙科复合树脂中,观察树脂挠曲强度的变化.方法:采用双酚A-甲基丙烯酸缩水甘油酯(Bis-GMA)和二甲基丙烯酸三甘醇酯(TEGDMA)为树脂基质,钡玻璃粉(BG)为主填料,选择纳米二氧化锆,纳米金刚石为功能填料,采用原位聚合法生成光固化牙科树脂,万能材料试验机测试其挠曲强度.结果:纳米二氧化锆和纳米金刚石之间不存在交互效应.不同浓度纳米二氧化锆之间有显著差异,不含纳米二氧化锆的树脂挠曲强度显著高于含5%纳米二氧化锆树脂的挠曲强度.不同浓度纳米金刚石之间有显著差异,含0.2%纳米金刚石的树脂挠曲强度显著高于含0.1%纳米金刚石树脂的挠曲强度.结论:含5%纳米二氧化锆、0.2%纳米金刚石的复合树脂颜色美观,其挠曲强度能达到相应的国家标准及ISO标准,能满足临床需要.  相似文献   

3.
目的:比较咬合诱导"活动矫治器"3 种基托材料的弯曲强度、冲击强度、粗糙度、弹性模量和色度,为临床选择材料提供依据.方法:以日进齿科材料有限公司生产的自然义齿基托聚合物Ⅱ型(以下简称日进)、日本株式会社而至生产的而至快速自凝基托树脂(以下简称而至)、上海二医张江生物材料有限公司生产的义齿基托树脂液Ⅱ型和上海医疗器械股份有限公司齿科材料厂生产的义齿基托树脂Ⅱ型(以下简称混合) 3 种基托材料为研究对象,对基托材料进行热压处理;测试挠曲强度、冲击强度、粗糙度及测试色度.测试结果用SPSS 12.0软件进行方差分析和Tamhane T2检验.结果:同一材料的"加压处理组"和"未加压处理组"比较,所有材料冲击强度的改变均有统计学意义,除此以外,个别材料挠曲强度和色度的改变有统计学意义.对于不同材料同一性能的比较,冲击强度:而至>"混合">日进;挠曲强度:日进>"混合">而至;弹性模量:日进>"混合">而至;粗糙度:而至>日进>"混合".结论:热压处理可以作为提高活动矫治器的基托性能的手段;3 种材料比较,各有长短.医师应该结合治疗实际情况选择最合适的材料.  相似文献   

4.
目的 研究冷热循环对义齿硬衬材料的颜色稳定性及挠曲强度的影响。方法 制作热凝树脂材料(日进自然I型)试件(64 mm×10 mm×2 mm)32块,随机分成4组,每组8块试件。分别为热凝树脂衬垫对照组;热凝树脂衬垫实验组;自凝硬衬材料(德山Rebase Ⅱ Fast)对照组;自凝硬衬材料实验组。所有试件衬垫前先进行5 000次冷热循环,然后分别加衬上述2种衬垫材料,形成基托材料与衬垫材料复合体(64.0 mm×10.0 mm×3.3 mm),实验组再行5 000次冷热循环。通过L*a*b*值及三点加载实验,比较实验组与对照组的颜色和挠曲强度差异。结果 德山硬衬材料实验组与对照组b*值间有统计学差异,但2种衬垫材料颜色变化均在临床可接受范围内。4组基托-衬垫复合体间挠曲强度无统计学差异。结论 德山Re-base Ⅱ Fast是一种方便易用的衬垫材料。  相似文献   

5.
目的 探讨自凝水凝胶软衬材料与义齿基托之间的粘结强度 ,并评价水份存在对该材料粘结强度的影响。同时将其与硅橡胶和自凝丙烯酸酯类软衬的粘结强度作比较。方法 用牙科型盒通过常规方法制备基托试样 ,使其长为 40mm ,粘结面为 10mm× 10mm。两粘结面之间预留 3mm间隙 (用金属模型 ) ,充填软衬材料 ,使其在室温下固化。用LJ - 5 0 0型拉力试验机测试软衬与基托粘结强度。结果 自凝水凝胶软衬的粘结强度明显优于SDG -A硅橡胶及自凝型丙烯酸酯类软衬 ,高达 5 .433Mpa。当浸入 37℃蒸馏水中 1d、3d ,其值有不同程度下降 ,并于第 3d后趋于稳定。结论 自凝水凝胶软衬材料具有很高的粘结强度 ,但水对其有一定影响。  相似文献   

6.
目的研究甲基丙烯酸偶联二氧化钛对树脂基托材料的机械性能的影响。方法按质量比2%、4%、6%及偶联剂有无添加在2种树脂基托材料中,检测各组试件的弯曲强度、弯曲弹性模量、挠度和冲击强度,并用扫描电镜观察表面结构的差异,分析添加量以及偶联剂对树脂基托材料机械性能的影响。采用SPSS12.0软件对数据进行统计学处理。结果弯曲强度和冲击强度随着二氧化钛添加量增加而下降,偶联剂能减缓下降量,偶联剂对弯曲弹性模量和挠度有显著影响(P<0.05)。日进MTi4%的弯曲强度(154.22Mpa)、冲击强度(12.50kJ/m2)和弯曲弹性模量(3643.72Mpa)分别显著大于日进TiO24%(P<0.05)。结论二氧化钛会降低基托树脂的机械性能,甲基丙烯酸能减缓其下降幅度。  相似文献   

7.
硅烷偶联剂的用量对PMMA/纳米ZrO2复合材料挠曲性能的影响   总被引:1,自引:0,他引:1  
目的:研究硅烷偶联剂Z-6030的不同用量对聚甲基丙烯酸甲酯(PMMA)/纳米ZrO2复合材料挠曲强度的影响。方法:采用不同用量的硅烷偶联剂Z-6030,在丙酮溶液中对纳米ZrO2颗粒进行表面修饰,将经过表面修饰的纳米ZrO2颗粒按照3.0%的添加量,利用原位聚合生成法,与义齿基托树脂(聚甲基丙烯酸甲酯,PMMA)11型粉剂及液剂聚合生成分散良好的PMMA/纳米ZrO2义齿基托复合材料,参照IS01567:1999的标准,制作实验组的标准试件。用未添加纳米ZrO2颗粒及偶联剂的义齿基托树脂(聚甲基丙烯酸甲酯,PMMA)Ⅱ型粉剂及液剂制作普通基托组的标准试件。用添加未经表面修饰的纳米ZrO2颗粒的义齿基托树脂(聚甲基丙烯酸甲酯,PMMA)Ⅱ型粉剂及液剂制作对照组的标准试件。用三点弯曲试验测试材料的挠曲强度,采用SAS6.12软件包对结果进行单因素方差分析。结果:硅烷偶联剂Z-6030的用量为3.5%组的挠曲强度最大,与普通基托组、对照组、2.0%组、4.0%组、4.5%组、5.0%组有显著性差异(P〈0.05),0.5%组、1.0%组、1.5%组、2.5%组、3.0%组、3.5%组各组间的挠曲强度差异无统计学意义(P〉0.05)。0.5%组、1.0%组、1.5%组、2.0%组、2.5%组、3.0%组、4.0%组、4.5%组、5.0%组、普通基托组及对照组各组之间的挠曲强度的差异无统计学意义(P〉0.05)。结论:适当用量的硅烷偶联剂Z-6030可以提高PMMA/纳米ZrO2义齿基托复合材料的挠曲强度,硅烷偶联剂Z-6030的最佳用量为纳米ZrO2颗粒质量的3.5%。  相似文献   

8.
不同聚合方法对基托树脂挠曲强度影响的实验研究   总被引:1,自引:0,他引:1  
目的在实验室条件下比较2种义齿基托树脂经过4种聚合方法处理后基托树脂的挠曲强度,为临床选择适宜的聚合方法提供依据。方法用金属模具制备相同尺寸的蜡型96个,失蜡后使用2种品牌的义齿基托树脂填胶,用4种方法进行热处理使其固化,用万能力学实验机检测基托树脂的挠曲强度.用双因素方差分析和多重比较进行统计学处理。结果两种基托树脂的挠曲强度具有显著差异(P〈0.01),不同聚合方法间基托树脂的挠曲强度除电热法与一组水浴方法存在显著差异外.其余组间无显著差异。结论基托树脂的挠曲强度和材料的性能有关,不同聚合方法对基托树脂的挠曲强度没有显著影响。  相似文献   

9.
目的:观察义齿基托树脂断面丙酮化学处理对树脂粘接修理后的弯曲强度的影响。方法:制作48个65mm×10mm×2.5mmPMMA热凝树脂试样,进行上三点弯曲试验,将压断后的试样随机分为6组,断面经常规预备后采用三种表面处理 方法:无处理、MMA单体涂刷30s、丙酮涂刷30s,分别用自凝和热凝树脂修理,然后在材料试验机上测定其弯曲强度。结果:丙酮处理热凝树脂修理组和自凝树脂修理组的弯曲强度高于同种树脂修理的无处理组和MMA处理组(P<0.01),丙酮处理热凝树脂修理组的弯曲强度最高,其强度恢复率为达94.14%;自凝和热凝树脂修理其弯曲强度无处理组和MMA处理组无显著性差别(P>0.05),其强度恢复率为原来的50%~60%。结论:丙酮化学处理树脂断面可提高义齿基托修理后的抗弯强度。  相似文献   

10.
目的在聚甲基丙烯酸甲酯粉(PMMA)中添加有机改性的蒙脱土制备纳米义齿基托树脂,以增强义齿基托树脂的挠曲性能。方法将蒙脱土经十六烷基三甲基溴化铵改性,形成有机化改性的蒙脱土,将其加入牙托粉中形成混和粉,混和粉与热凝牙托水调和后经加热固化形成纳米义齿基托树脂。用X射-线衍射(XRD)和透射电子显微镜(TEM)表征了固化后材料的结构,用三点挠曲试验测量固化后材料的挠曲强度和挠曲弹性模量。用一维方差分析法评价有机化蒙脱土的量对挠曲强度的挠曲弹性模量的影响。结果 XRD、TEM证实当蒙脱土在混合粉中的量为3%和5%时,蒙脱土在PMMA基质中形成部份剥离和插层结构;当蒙脱土在混合粉中的量为3%时,挠曲强度达最大,进一步增加蒙脱土的量,材料的挠曲强度降低。当混和粉中有机蒙脱土的量在1%~10%时,挠曲弹性模量随有机蒙脱土的量增加而增加。一维方差分析表明当混和粉中有机蒙脱土的量为3%时,实验组的挠曲强度与挠曲弹性模量均存在显著性差异(n=5,P〈0.05)。结论牙托粉中蒙脱土的量对义齿基托树脂的挠曲性能有显著性影响。  相似文献   

11.
树脂型氟离子缓释正畸粘接剂粘接性能的研究   总被引:1,自引:0,他引:1  
目的 评价树脂型氟离子缓释正畸粘接剂的粘接性能 ,比较树脂型氟离子缓释正畸粘接剂 (FRA)和目前临床常用的两种正畸粘接剂的抗张粘接强度和抗剪粘接强度。方法 分别用 3种粘接剂在牛牙釉质上粘接金属托槽 ,在离体实验条件下 ,测试其抗张粘接强度和抗剪粘接强度并进行比较。结果  3种粘接剂之间抗张粘接强度和抗剪粘接强度均没有统计学差异 (P >0 .0 5 ) ,且在 3个月的时间内 ,FRA中氟离子的释放没有对FRA的粘接强度产生不利的影响。结论 FRA可以达到临床使用的粘接强度要求。  相似文献   

12.
Abstract

Objective. The aim of this study was to evaluate the efficacy of the microtensile, microshear and shear bond strength test methods to assess the bond strength of two self-etch adhesives and one etch&rinse adhesive on dentin. Materials and methods: Seventy-five extracted human molars were ground to expose their flat dentin surfaces and randomly assigned to one of three groups according to the type of test method (15 for microtensile, 15 for microshear, 45 for shear). Each of these groups was then assigned to three sub-groups according to the bonding systems (Clearfil SE Bond, Kuraray; G Bond, GC; Prime&Bond NT, Dentsply) used. Then, 15 specimens were prepared for each sub-group according to the test method employed (n = 15). After being stored in distilled water at 37°C for 24 h, the specimens were placed in a universal testing machine for three test methods and stressed at a crosshead speed of 0.5 mm/min. Mean bond strengths were analyzed using Kruskall-Wallis and Mann-Whitney U-tests at a significance level of p < 0.05. Results. The microtensile test had the highest bond strength (p = 0.046). Clearfil SE Bond and Prime&Bond NT produced significantly higher values than the G Bond in the microtensile bond test (p < 0.05), whereas no significant differences were found among the adhesives in the microshear bond test (p > 0.05). For the shear test, Clearfil SE Bond showed higher bond strength than Prime&Bond NT and G Bond (p < 0.05). Conclusion: Bond strength to dentin depends on the material and the test method used.  相似文献   

13.
目的:对比研究4种粘接剂抗压强度及挠曲强度的差异.方法:选用树脂粘接剂Compolute,复合树脂Resinomer,树脂加强型玻璃离子Vitremer Luting及传统玻璃离子Ketac Cem4种粘接剂,分别制作抗压强度及挠曲强度的标准试件,每组10个.万能试验机测试其抗压强度及挠曲强度值,采用单因素方差分析及组间两两比较的LSD-t检验进行统计分析.结果:抗压强度组:Compolute为245.73±23.17MPa,Resinomer为153.50±18.59MPa,Vitremer Luting为61.89±10.92MPa,Ketac Cem为163.78±17.07 MPa.Ketac Cem和Resinomer组,其余各组组间两两比较差异均有统计学意义,P<0.05.抗压强度由高到低的顺序为Compolute>Ketac Cem>Resinomer>Vitremer Luting;挠曲强度组:Compolute为79.40±15.02MPa,Resinomer为102.18±19.61MPa,Vitremer Luting为20.70±3.89MPa,Ke切c Cem为21.04±4.02MPa.除后两组外,其余各组两两比较差异均有统计学意义,P <0.05.挠曲强度由高到低的顺序为Resinomer>Compolute>Ketac Cem>Vitremer Luting.结论:与Vitremer Luting及Ketac Cem相比,Compolute表现较高的抗压强度及挠曲强度,Resinomer则具有较高的挠曲强度及较低的抗压强度,临床上可根据不同修复需求选择合适的粘接系统.  相似文献   

14.
Purpose: Clinicians are still confused about the choice of repair method, which depends on factors such as the length of time required for processing, the mechanical strength of the repaired material, and the effect of stress concentration in the acrylic resins before the repair. The aim was to determine the impact and flexural strength characteristics, such as stress at yield, Young's modulus, and displacement at yield of denture base resins fractured and repaired by three methods using heat‐, auto‐, and visible light‐polymerized acrylic resins. Material and Methods: For impact and flexural strength tests, 18 rectangular specimens measuring 50 × 6 × 4 mm3 and 64 × 10 × 3.3 mm3, respectively, were processed using Impact 2000, Lucitone 550, Impact 1500, and QC‐20 acrylic resins. Fracture tests were performed according to ISO1567:1999. Afterward, all fractured specimens were stored in distilled water at 37°C for 7 days, and then repaired with (1) the same acrylic resin used for specimen fabrication (n = 6), (2) an autopolymerized acrylic resin (TruRepair, n = 6), and (3) a visible light acrylic resin (Versyo.com, n = 6). The repaired specimens were again submitted to the same fracture tests, and the failures were classified as adhesive or cohesive. Data from all mechanical tests after repair by the different methods were submitted to two‐way ANOVA, and mean values were compared by the Tukey test. Results: All acrylic resins showed adhesive fractures after impact and flexural strength tests. Differences (p < 0.05) were found among repair methods for all acrylic resins studied, with the exception of displacement at yield, which showed similar values for repairs with auto‐ and visible light‐polymerized acrylic resins. The highest values for impact strength, stress, and displacement at yield were obtained when the repair was made with the same resin the specimen was made of. Conclusion: Denture base acrylic resins repaired with the same resin they were made of showed greater fracture strength.  相似文献   

15.
目的研究临床常用的多晶体氧化铝陶瓷托槽CrystalineⅣ(Tomy,Japan)剪切及拉伸粘接强度。方法 15颗离体上颌双尖牙用于剪切粘接实验,15颗离体下颌双尖牙用于拉伸粘接实验。使用37%液体磷酸和京津釉质粘接剂粘接CrystalineⅣ,在0.9%生理盐水中室温保存24小时。电子万能试验机检测剪切及拉伸粘接强度。托槽脱落后记录粘接剂残留指数(ARI,adhesive remnant index),陶瓷托槽的折断数目和釉质表面出现肉眼可见缺损的牙齿数目。结果 Crystaline IV的剪切和拉伸粘接强度分别为14.47±2.43MPa和6.53±2.26MPa,剪切粘接强度显著高于拉伸粘接强度。两种加载方式的主要去除部位均在粘接剂内,所有样本未出现陶瓷托槽折断和肉眼可见的釉质缺损。结论使用京津釉质粘接剂粘接CrystalineⅣ能够获得满足临床治疗需要的剪切及拉伸粘接强度,剪切粘接强度显著高于拉伸粘接强度。加载拉伸力可能是相对安全的去除陶瓷托槽的方法。  相似文献   

16.
PURPOSE: The present in vitro study examined 3 mechanical properties, namely compressive, flexural, and diametral tensile strength, of various commercially available cements and core materials as a function of time after mixing. MATERIALS AND METHODS: The examined materials were 2 cermet cements (Ketac Silver [ESPE, Seefeld, Germany] and Chelon Silver [ESPE]), 1 metal-reinforced glass ionomer cement (Miracle Mix [GC Dental Industrial Corp, Tokyo, Japan]), 2 conventional glass ionomer cements (Ketac Bond [ESPE] and Ketac Cem [ESPE]), 1 standard cure zinc phosphate cement (Harvard Cement [Richter and Hoffmann, Berlin, Germany]), and 1 zinc phosphate cement with the addition of 30% silver amalgam alloy powder (Harvard Cement 70% with Dispersalloy 30% [Richter and Hoffmann/Johnson and Johnson, East Windsor, NJ]). Properties were measured using a universal testing machine at 15 minutes, 1 hour, and 24 hours after first mixing. RESULTS: Compressive strengths varied widely between the 3 times of measurement from 5.8 +/- 6.6 MPa for Ketac Cem to 144.3 +/- 10.2 MPa for Ketac Silver. Twenty-four hours after mixing, the Bonferroni test showed significant (p 相似文献   

17.
目的:初步探讨氧化锆陶瓷表面制备衬里层对其锆-瓷结合力的影响.材料方法:16片氧化锆陶瓷试件致密烧结后随机分为两组,标记为C组和L组,C组空白对照、L组预先烧结一薄层衬里层即Vita VM9Effect Bonder(Eb).全部试件表面烧结饰瓷后应用平行剪切实验进行锆-瓷结合强度测试,并通过扫描电镜观察破坏界面的表面形貌.结果:L组的平行剪切强度为26.96±2.78MPa、C组剪切强度为22.15±2.29MPa,两组锆-瓷界面破坏方式均以粘接破坏为主.在氧化锆表面制备衬里层后其剪切强度显著提高,二者差异有统计学意义(P<0.05).结论:在致密烧结后氧化锆表面预先烧结一薄层Vita VM9 Effect Bonder(Eb)来制备衬里层,能一定程度提高锆瓷结合强度.  相似文献   

18.
PURPOSE: Compressive and diametral tensile strengths (DTSs) of core materials are thought to be important, because cores usually replace a large bulk of tooth structure and should provide sufficient strength to resist intraoral tensile and compressive forces. This study was undertaken to compare the mechanical properties of materials used for direct core foundations. MATERIAL AND METHODS: The differences between the compressive and DTSs of six core materials, including Duralloy (high-copper amalgam), Grandio (visible light-cured nanohybrid resin composite), Admira (organically modified ceramic), Filtek P60 (packable composite resin), Rebilda DC (dual-cure adhesive core material), and Argion Molar (silver-reinforced glass ionomer cement), were tested. A total of 120 specimens, half for the compressive strength (CS) test (6 mm in height, 4 mm in diameter) and the other half for the DTS test (6 mm in diameter, 3 mm in thickness), were prepared. The specimens were stored at room temperature in distilled water for 7 days. The Lloyd testing machine was used to load the specimens at a crosshead speed 0.5 cm/min, and the strength values were determined in MPa. RESULTS: The compressive and DTS test values (in MPa), respectively, of the materials were: Admira (361, 44); Filtek P60 (331, 55); Grandio (294, 53); Rebilda DC (279, 42); Duralloy (184, 40); and Argion Molar (107, 9). Kruskal-Wallis test was computed, and multiple comparisons test discerned many differences among materials (p < 0.05). CONCLUSION: Packable composite resin (Filtek P60), visible light cured nanohybrid resin composite (Grandio), and organically-modified ceramic (Admira) had higher compressive and DTS values than the other materials.  相似文献   

19.
目的 研究添加纳米聚膦腈对聚氨酯材料力学强度的影响。方法 将3种实验组材料(纯聚氨酯材料(PU)、含1%纳米聚膦腈的聚氨酯材料(1% PSZ-PU)、含5%纳米聚膦腈的聚氨酯材料(5% PSZ-PU))以及对照组自固化型硅橡胶软衬材料,分别经历0次、1 000次、3 000次冷热循环后测试其拉伸强度和撕裂强度,并进行统计学分析。结果 冷热循环0次、1 000次、3 000次后3种聚氨酯复合材料拉伸强度依次为:PU组32.85 MPa、23.09 MPa和24.36 MPa;1% PSZ-PU组34.98 MPa、25.33 MPa和25.52 MPa;5% PSZ-PU组32.29 MPa、28.22 MPa和26.10 MPa。撕裂强度依次为:PU组40.64 kN/m、37.96 kN/m和40.69 kN/m;1% PSZ-PU组40.87 kN/m、41.01 kN/m和40.63 kN/m;5% PSZ-PU组42.73 kN/m、43.28 kN/m和41.59 kN/m,它们均大于对照组硅橡胶材料的拉伸强度和撕裂强度,其中实验组材料组间比较时,除循环1 000次后,5% PZS-PU和1% PZS-PU的拉伸强度差异具有统计学意义(P<0.05)外,其他循环次数中3组实验组材料组间的拉伸强度和撕裂强度的差异均无统计学意义(P>0.05)。结论 3组聚氨酯复合材料的拉伸强度和撕裂强度均高于对照组硅橡胶类软衬材料,5%以内的聚膦腈纳米球添加剂量未对聚氨酯的拉伸强度和撕裂强度产生明显的增强作用。  相似文献   

20.
目的:探讨二期高温高压处理对Artglass玻璃瓷材料机械性能的影响。方法:用Artglass DA3材料分别制作20个抗压强度和直径拉伸强度测试试件,所有试件在UniXS频闪聚合机中常规聚合,而后随机分为两组,一组为对照组,另一组用国产自控多用途牙用树脂聚合器进行二期热压处理,温度120℃,压力0.6Mpa,时间7min;用Instron1195万能拉力测试仪测得抗压强度和直径拉伸强度,对二期热压处理前后的测试值用单因素方差分析方法进行比较。结果:二期热压处理后Artglass的抗压强度和直径拉伸强度都有了显著提高,提高幅度分别为16%和9%(P<0.01)。结论:二期热压处理可以明显提高Artglass玻璃瓷材料的抗压强度和直径拉伸强度。  相似文献   

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