五种光固化复合树脂充填材料的机械强度比较

目的:比较Tetri cRCeram HB、Ceram.XTMduo-牙釉质色、Ceram.XTMduo-牙本质色、Qu ixF ilTM和Esthet.XTM五种光固化复合树脂的挠曲强度、压缩强度、固化深度和显微硬度,为临床操作中材料的选择提供依据。方法:根据ISO 4049:2000,采用电子式万能试验机测试材料的挠曲强度、压缩强度;固化深度测试仪测试材料的固化深度;动态超显微硬度仪测试材料的硬度。测试结果用SPSS软件进行方差分析和posthoc Tukey HSD检验,α=0.05。结果:挠曲强度比较,Esthet.XTM为(121.3250±17.1491)MPa,较其他材料大,其他材料之间无统计学差异。压缩强度比较,Ceram.XTMduo-牙釉质色(313.3800±36.8904)MPa和Esthet.XTM(338.4200±25.0402)MPa较其他3种大,两者之间无统计学差别。固化深度比较,Ceram.XTMduo-牙釉质色(2.9280±0.1158)mm和Qu ix.F ilTM(2.8160±0.2027)mm较其他3种大,两者间无统计学差异。硬度比较,Tetric RCeram HB(73.1408±20.8823)GPa与Qu ix F ilTM(67.9288±17.6141)GPa较其他3种大,两者之间也无统计学差异。综合各方面指标,Esthet.XTM的机械性能较高。结论:所测试各种复合树脂的机械性能不同,各有优缺点,在临床操作中应当根据需要选择具有不同机械性能的材料。     

卤素和LED光固化灯照射复合树脂的机械强度比较

目的探讨3M2500型卤素光固化灯和3M FreeLight型LED光固化灯对光固化复合树脂机械强度及固化深度的影响。方法用WD-5A型电子拉力试验机、DUH-W201S型动态超显微硬度计2种仪器,通过测试比较卤素光固化灯和LED光固化灯照射Tetric ceram HB(Vivadent)A2色光固化复合树脂后其挠曲强度、压缩强度、表面硬度、固化深度的差异,从而比较3M2500型卤素光固化灯和3M FreeLight型LED光固化灯的性能。结果卤素光固化灯照射Tetric ceram HB复合树脂40s,LED光固化灯照射Tetric ceram HB10s,前者固化深度平均可达3.98mm,后者固化深度平均可达2.136mm,两者均可完全固化2mm,LED光固化灯固化树脂深度低于卤素光固化灯;表面硬度DHT115平均值分别为73.292MPa和39.668MPa,统计学分析95%水平有差别(P<0.05),LED灯对应的树脂硬度低于卤素灯;压缩强度平均值分别为242.1MPa和287.7MPa,统计学分析95%水平无明显差别(P>0.05);挠曲强度平均值分别为88.9MPa和97.0MPa,统计学分析95%水平无明显差别(P>0.05)。结论LED灯照射Tetric ceram HB复合树脂10s能达到卤素灯照射Tetric ceram HB复合树脂40s的聚合水平,适合于口腔临床应用。     

复合树脂核材料的弯曲强度性能研究

目的:采用三点弯曲实验的方法测量3种复合树脂核材料的弯曲强度。方法:本实验使用的3种复合树脂核材料分别为DCFlowCore、Bisfil-Core和LuxaCore。每种材料各制作6个大小为(2.0±0.1)mm×(3.0±0.1)mm×(25.0±0.1)mm的矩形试件。试件在Instron万能材料测试机上测试其弯曲强度,跨距为(20.0±0.1)mm,加载速度为0.5mm/min,使用单因素方差分析对测量数据进行统计学检验。结果:3种材料的弯曲强度值分别为:DCFlowCore(137.96±9.48)MPa,Bisfil-Core(123.82±12.99)MPa,LuxaCore(110.11±10.03)MPa。统计检验的结果显示,DCFlowCore与Bisfil-Core之间(P<0.041)、DCFlowCore与LuxaCore之间(P<0.001)、Bisfil-Core与LuxaCore之间(P<0.047)均有显著性差异。结论:从本实验的结果来看,3种核材料的弯曲强度均可以满足临床需要,以DCFlowCore的弯曲强度值最高。     

光固化复合树脂修复楔状缺损不同方法的比较

光固化复合树脂修复楔状缺损不同方法的比较河南医科大学口腔系（４５００５２）殷勤河南省人民医院崔广庆楔状缺损在牙体硬组织的非龋性疾病中发病率比较高，常发生于患者多个牙齿唇颊面的颈部近龈缘处。由于光固化复合树脂的问世，给楔状缺损修复带来了很大方便。本文旨...     

口内喷砂增强Ni-Cr合金与复合树脂间粘接强度的研究

目的研究崩瓷修复中,口内喷砂对Ni-Cr合金与复合树脂间粘接强度的影响。方法12个Ni-Cr合金试件随机分2组,实验组合金表面模拟口内喷砂,对照组不进行口内喷砂,采用alloyprimer金属处理剂对金属表面处理,然后使用VocoCimara瓷修补系统粘接修复,经37℃恒温水浴2 4小时后,测定金属试件与复合树脂之间剪切粘接强度,进行统计分析。结果经过模拟口内喷砂的实验组合金与复合树脂之间剪切粘接强度显著高于对照组(P <0 .0 5 )。2 0倍体视镜观察两组断裂面均位于金属-复合树脂界面。结论口内喷砂可增强Ni-Cr合金-复合树脂间剪切粘接强度。     

光固化复合树脂修补活髓牙缺损几种垫底材料的比较

为了选择良好的垫底材料用于活够前牙缺损的光固化复合树脂的修复，本研究采用高级牙用羧聚陶瓷、丁香油粘固粉、磷酸锌粘固粉、氢氧化钙糊剂作为垫底材料，用于前牙牙本质浅层及牙本质深层损坏的光固化树脂修复。比较以上4种材料在保护牙髓，以及充填体牢固程度和颜色等方面的差异，结果证明高级牙用羧聚陶瓷明显优于其他材料，是目前较为理想的前牙光固化树脂修复的垫底材料。     

光固化复合树脂修补金-瓷冠桥的临床研究

随着金 -瓷冠桥的广泛应用 ,瓷折裂的修补日益需要 .对于多个牙单位联冠、长桥 ,瓷折裂后要完整摘下修复体进行修补是极困难的 .即使拆下 ,由于工厂化的义齿加工使医技之间空间距离增加 ,同时国内临床单位极少配备椅旁烤瓷设备 ,使补瓷成为困难 ,被迫进行口腔内修补 .本研究用光固化树脂在偶联剂作用下修补瓷部分脱落 ,取得良好效果 ,与单纯使用进口材料相比 ,成本低 .材料和方法1　材料 :光固化树脂 :　 3 M Restorative Z1 0 0Vita TMShade粘接剂 :　 Panavia2 1树脂粘结剂偶联剂 :　 5% KH-570 有机硅烷酒精溶液 酸蚀剂 :　 5%氢氟…     

5种后牙光固化复合树脂的三种性能测试

用可见光照射Ｚ１００、ＥｓｔｉｏＬＣ、Ｈｅｌｉｏｍｏｌａｒ、Ｏｃｃｌｕｓｉｎ、Ｌｉｔｅ－ＦｉｌⅡ５种复合树脂。通过测定其压缩强度、径向拉伸强度及表面硬度，研究５种不同的光固化材料的某些机械性能的差异。实验结果表明：不同的光固化材料，其压缩强度、径向拉伸强度及表面硬度均有差异。Ｏｃｃｌｕｓｉｎ、Ｚ１００、Ｌｉｔｅ－ＦｉｌⅡ３种后牙复合树脂物理机械性能较好，而适用于前后牙的Ｈｅｌｉｏｍｏｌａｒ、ＥｓｔｉｏＬＣ则较差     

光固化复合树脂修补活髓牙缺损几种垫底材料的比较

为了选择良好的垫底材料用于活髓前牙缺损的光固化复合树脂的修复，本研究采用高级牙用羧聚陶瓷，丁香油粘固粉，磷酸锌粘固粉，氢氧化钙糊剂作为垫底材料，用于前牙牙本质浅层及牙本质深层损坏的光固化树脂修复。比较以上４种材料在保护牙髓，以及充填体牢固程度和颜色等单方面的差异，结果证明高级牙用羧聚陶瓷明显优于其他材料，是目前较为到时候的前牙光固化树脂修复的垫底材料。     

预浸润玻璃纤维强化复合树脂的力学性能

大学口腔医院　修复科;2.北京大学口腔医院　材料教研室,北京100081) [摘要]　目的　研究预浸润玻璃纤维对不同复合树脂的强化效果。方法　制作Sinfony和belleGlass两种复合树脂的加入和不加预浸润玻璃纤维的标准试件(25 mm×2 mm×2 mm),于(37±1)℃的蒸馏水环境中保存24 h后,在万能力学试验机上测试弯曲强度和弹性模量。结果　Sinfony复合树脂加入纤维后弯曲强度和弹性模量显著提高,分别为(555·76±67·31)MPa和(12·59±3·06)GPa,较不加玻璃纤维试件平均提高了4·9和2·5倍(P=0);belleGlass复合树脂加入纤维后弹性模量有提高,为(14·10±2·88)Gpa,较不加玻璃纤维试件平均提高了0·9倍(P=0),而弯曲强度提高不明显。结论　预浸润玻璃纤维可以显著提高复合树脂的力学性能,但对不同复合树脂的强化效果有明显差别。     

不同偶联剂对瓷和树脂化学粘结的影响

目的：比较不同偶联剂对瓷和树脂化学粘结的影响。方法：取瓷试件8组，分别不涂偶联剂，涂Cerinate Primer和6种自制偶联剂，与树脂粘结后测剪切强度。另取3组瓷试件分别涂粘结强度最高的新配方偶联剂、Cerinate Primer、不涂偶联剂，与树脂粘结后观察粘结密合度。结果：C配方可产生8．02MPa剪切强度，粘结界面缝隙为0．91μm，Cerinate Primer相应为3．66MPa和3．87μm，不涂偶联剂为0．42MPa和5．16μm。结论：C配方偶联剂使瓷和树脂产生了最高的化学粘结强度，并显著提高了粘结密合度。     

Bonding of Composite Resin to Contaminated Human Enamel and Dentin

Purpose The purpose of this in vitro study was to evaluate the bond strengths of a bonding agent and composite resin system to human enamel and dentin treated with five contaminants (saliva, plasma, zinc oxide–eugenol cement, noneugenol zinc oxide cement, and handpiece lubricant) using air, moisture, and water as controls. Materials and Methods A commercial bonding agent (Gluma 2000; Bayer AG, Dormagen, Germany) and its composite (Pekafill; Bayer AG) were applied to tooth structure under two conditions (contaminated and re-etched). Samples were debonded in tension after 24 hours using an inverted, truncated cone bond test. Results Among the controls, the highest bond strengths were obtained to enamel (20 MPa) and dentin (12 MPa) with air drying. Contaminants lowered the bond strength by 20% to 100%. Re-etching without additional mechanical preparation resulted in bond strengths similar to the air control. Conclusions Bond strength of Gluma 2000/Pekafill to tooth structure is sensitive to common forms of contamination but can be improved by re-etching after contamination occurs.     

不同类型偶联剂处理对瓷和树脂黏接界面的影响

目的：比较瓷表面不同酸蚀状态下,4种硅烷偶联剂对瓷和树脂之间黏接界面的影响。方法：将40个瓷试件按照所使用硅烷偶联剂的不同分为4组,每组包括磷酸和HF处理2个亚组各5个试件。表面处理后将瓷试件与复合树脂黏接,将黏接完成后的试件切取纵断面,电镜下观察不同界面形态在整个黏接界面所占比例。结果：HF处理与2种双组分偶联剂相配合产生的黏接界面完整率最高（P〈0．05）,2种单组分偶联剂与HF配合使用的效果同2种双组分偶联剂与磷酸配合使用的效果没有显著差异（P〉0.05）。结论：不同种类偶联剂对瓷和树脂之间的黏接密合度有明显影响,选用合适的双组分陶瓷偶联剂与磷酸处理相配合,可以获得较为理想的黏接界面形态。     

三种酸蚀剂联合偶联剂对Cerinate瓷与树脂粘结强度的影响

目的：评价三种陶瓷酸蚀剂联合偶联剂对Cerinate瓷与树脂粘结强度的影响。方法：将252个Cerinate瓷试件分为3组,每组84个试件,分别用自制A配方（含2.5%氢氟酸）﹑B配方（含6%氢氟酸）、C配方（含10%氢氟酸）陶瓷酸蚀剂处理0 s﹑30 s﹑60 s﹑90 s、120 s、150 s、180 s后,一半使用偶联剂,另一半不使用偶联剂,与树脂粘结后测试其粘结强度。结果：无偶联剂组酸蚀30 s后C配方的剪切强度为27.46 MPa,偶联剂组在酸蚀30 s后C配方剪切强度可达31.08 MPa,酸蚀时间对粘结强度无明显影响。结论：C配方配合偶联剂较短酸蚀时间内可获得较理想的粘结强度。     

Analysis of depth of the microporosity in a nickel-chromium system alloy - effects of electrolytic,chemical and sandblasting etching

The present study was designed to analyse the average depth of the microporosity of a nickel-chromium (Ni-Cr) system alloy (Verabond II). The metal surface was subject to one of the following surface treatment: (i) Electrolytic etching in nitric acid 0.5 N at a current density of 250 mA cm(-2); (ii) chemical etching with CG-Etch etchant; and (iii) Sandblasting with alumina particles 50 microm. Half of the samples were polished before the surface treatments. The depth of porosity was measured through photomicrographs (500x) with a profilometer, and the data were statistically analysed using an analysis of variance (anova) followed by Tukey's test. The conclusions were (i) Differents surface treatment of the Ni-Cr system alloy lead to different depths of microporosity; (ii) The greatest depth of porosity was observed in non-polished alloy; (iii) The greatest and identical depth of microporosity was observed following electrolytic etching and chemical etching; (iv) The least and identical depth of microporosity was observed with chemical etching and sandblasting with alumina particles 50 microm, and (v) Chemical etching showed an intermediary depth.     

Effect of Surface Preparation Using Ethyl Acetate on the Shear Bond Strength of Repair Resin to Denture Base Resin

Purpose : This study evaluated the effect of using ethyl acetate as a surface preparation agent on the shear bond strength of repair resin to denture base resin.
Materials and Methods : The flat surfaces of a heat-processed denture base resin were prepared with one of the following: (1) without preparation, (2) 60-second application of ethyl acetate, (3) 120-second application of ethyl acetate, (4) 180-second application of ethyl acetate, and (5) 5-second application of dichloromethane. An autopolymerizing repair resin was applied. The specimens were then immersed in 37°C distilled water for 24 hours. The specimens in groups 1, 3, and 5 were thermocycled up to 10,000 times in water between 5 and 55°C with a 1-minute dwell time at each temperature. The shear bond strengths were determined at a crosshead speed of 1.0 mm/min (n = 10). The morphological changes in the repair surfaces after preparation were observed with a scanning electron microscope.
Results : The shear bond strengths of groups 3 and 5 were significantly higher than the other groups before thermocycling ( p < 0.05). The shear bond strengths of group 3 were significantly lower than those of group 5 after thermocycling ( p < 0.05). The scanning electron microscope (SEM) views showed that the dissolution progressed deeper with the preparation duration.
Conclusions : The 120-second surface application of ethyl acetate enhanced the shear bond strength between the repair resin and the denture base resin, although the bond durability was inferior to that of the conventional surface preparation.     

Reinforcement of Denture Base Resin with Glass Fillers

PURPOSE: This study evaluated the effect of short glass fibers on the transverse strength of a heat-polymerized acrylic resin denture base material. MATERIALS AND METHODS: Four groups of specimens (n = 10) were fabricated according to the ISO standard for the transverse strength test. E-glass fibers were triturated to produce short fibers of different lengths. Specimens for Group 1 (control) were made of unfilled polymethylmethacrylate (PMMA). For group 2, the PMMA powder was modified with 0.1 g of dry glass fibers. For group 3, the PMMA powder was modified with 0.1 g of silanized glass fibers. For group 4, the PMMA powder was modified with 0.2 g of silanized glass fibers. A three-point loading test was used to determine the transverse strength of the tested specimens. The fracture surface of each specimen was evaluated using SEM. RESULTS: The addition of untreated glass fibers increased the transverse strength by 11% but produced some porosity in the polymeric matrix. The addition of silane-treated glass fibers increased the transverse strength of PMMA by 28% for group 3 and by 26% for group 4, and produced a dense structure for the polymer-fiber composite. CONCLUSION: The transverse strength of PMMA can be slightly increased by the addition of short glass fibers.