10种复合树脂颜色稳定性与吸水溶解性研究

目的 评价10种光固化复合树脂在不同溶液中的颜色稳定性及吸水溶解性能。方法 10种光固化复合树脂分别为：BeautifilⅡ(B2)、Ceram. X One Universal (CXU)、Charisma (CS)、Charisma Diamond (CD)、Denfil (DF)、DX. Universal (DXU)、Filtek Z250 (Z250)、Filtek Z350 XT (Z350)、FS-1 (FS)、Magnafill Putty(MP)。每种树脂材料各制作20个试件,随机分为4组(n=5),分别浸入蒸馏水(对照组)、咖喱、咖啡和红酒28 d,分光光度计测量试件浸入前及浸入后1、7、14、21和28 d的色度值(CIE L^*a^*b^*),计算染色前后色差值。根据ISO 4049:2019标准,每种材料制作3个试件,测量材料的吸水性和溶解性。采用三因素方差分析评估树脂材料、染液、染色时间对染色前后色差值(ΔE)的影响,采用单因素方差分析比较不同材料的吸水值和溶解值变化。结果 随着染色时间增加,所有试...     

3种抛光系统对光固化复合树脂表面粗糙度影响的实验研究

目的:研究不同抛光处理对光固化复合树脂表面粗糙度的影响,为临床选择合适的抛光系统提供参考.方法:选择Filtek Z250复合树脂制作30个样本试件,随机分为3组,分别用3种不同的抛光系统(Sof-lex,Enhance,Super-Snap)处理,扫描电镜观察抛光前后的表面形态,表面粗糙度仪测定其粗糙度.结果:不同抛光系统处理Filtek Z250复合树脂试件后,单因素方差分析比较3组表面粗糙度Ra值的总体均数间差异,显示有统计学意义(P<0.05);SNK检验对各抛光系统组进行两两比较,Sof-lex和Super-Snap两组之间无明显差异,但二者与Enhance组比较存在显著性差异(P<0.05).结论:在本实验条件下,对于Filtek Z250复合树脂的抛光处理,3种抛光系统中Sof-lex和Super-Snap处理后表面粗糙度值较低,抛光效果优于En-hance抛光系统.     

无机填料含量对流动树脂挠曲强度和压缩强度影响体外研究

目的 研究无机填料含量对流动树脂的挠曲强度和压缩强度的影响。方法 于2012年4月在北京大学口腔医学院口腔材料研究室测定Clearfil Flow、Filtek Flow、DenFil Flow、Filtek Z250复合树脂无机填料的质量分数、挠曲强度和压缩强度。结果 流动树脂中无机填料的质量分数与其挠曲强度的变化顺序相一致,由小到大依次为DenFil Flow、Filtek Flow、Clearfil Flow、Filtek Z250。DenFil Flow与其余3组间挠曲强度差异均有统计学意义（P < 0.05）,Filtek Flow与Clearfil Flow、Filtek Z250间挠曲强度差异亦均有统计学意义（P＜0.05）,但Clearfil Flow与Filtek Z250间挠曲强度差异无统计学意义（P＞0.05）。4种材料压缩强度差异均无统计学意义（P＞0.05）。结论 高填料型流动树脂的挠曲强度远高于普通流动树脂,并且可达到我国医药行业标准规定牙合面修复材料的要求;压缩强度与前后牙通用树脂相近,可以满足临床应用的需要。     

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目的研究无机填料含量对流动树脂的挠曲强度和压缩强度的影响。方法于2012年4月在北京大学口腔医学院口腔材料研究室测定Clearfil Flow、Filtek Flow、DenFil Flow、Filtek Z250复合树脂无机填料的质量分数、挠曲强度和压缩强度。结果流动树脂中无机填料的质量分数与其挠曲强度的变化顺序相一致,由小到大依次为DenFil Flow、Filtek Flow、Clearfil Flow、Filtek Z250。DenFil Flow与其余3组间挠曲强度差异均有统计学意义（P〈0.05）,Filtek Flow与Clearfil Flow、Filtek Z250间挠曲强度差异亦均有统计学意义（P〈0.05）,但Clearfil Flow与Filtek Z250间挠曲强度差异无统计学意义（P〉0.05）。4种材料压缩强度差异均无统计学意义（P〉0.05）。结论高填料型流动树脂的挠曲强度远高于普通流动树脂,并且可达到我国医药行业标准规定面修复材料的要求;压缩强度与前后牙通用树脂相近,可以满足临床应用的需要。     

抛光对三种复合树脂表面粗糙度影响的实验研究

目的：采用临床上常用的3种充填用光固化复合树脂进行抛光后对比研究,为临床医师选择适当的牙体充填材料提供指导。方法：选择3种临床常用的前后牙通用光固化型复合树脂（Filtek Z250,Spectrum TPH,CHARISMA）,均用Sof-lex抛光系统修整、抛光,扫描电镜观察抛光前和抛光后的表面形态,并用表面粗糙度仪测定其粗糙度,对检测结果进行统计学分析。结果：3种复合树脂经同一种抛光系统处理后粗糙度值均增大,不同复合树脂之间的两两比较显示存在显著性差异;Filtek Z250组表面粗糙度值（Surface Roughness,Ra）无论抛光前后,均较其他两种树脂的Ra值小。结论：用Sof-lex抛光系统修整、抛光,Filtek Z250在三种复合树脂中有较/最佳的抛光性能。     

人工老化对全瓷贴面树脂粘结剂颜色稳定性的影响

目的研究人工老化对全瓷贴面树脂粘结剂颜色的影响。方法用VITABLOCS MARK-Ⅱ制作厚度为1 mm的试件40个,随机分为4组(n=10)。分别采用Superbond C&B化学固化粘结剂、VariolinkⅡ双重固化粘结剂、RelyX Veneer光固化粘结剂和Filtek Z350 Flow流动复合树脂进行粘结,4种粘结剂颜色均为A3。在黑暗环境下保持24 h后用色度计测量色度值。再将各组试件置于紫外光老化实验箱中进行老化后再次测量其色度值,比较4种树脂粘结剂的颜色稳定性。选定ΔE<3为临床可接受范围。结果 Superbond C&B、VariolinkⅡ、RelyX Veneer和Filtek Z350 Flow粘结剂的ΔE分别为2.32±0.21,2.50±0.29,0.68±0.24和0.79±0.20。其中Superbond C&B和VariolinkⅡ的ΔE高于其他组(P<0.05)。Superbond C&B和VariolinkⅡ之间,RelyX Veneer和Filtek Z350 Flow之间无显著性差异(P>0.05)。结论 4种树脂粘结剂在人工老化后均出现不同程度的颜色变化,但这种颜色改变程度在临床美学要求范围内。RelyX Veneer和Filtek Z350 Flow树脂具有较好的颜色稳定性。     

不同处理方式对通用粘接剂光固化后唾液污染的乳牙牙本质粘接强度的影响

［摘要］ 目的 探究不同处理方式对通用粘接剂光固化后唾液污染的乳牙牙本质粘接强度的影响。方法 选取人60颗无龋坏乳磨牙,磨除牙合面牙釉质至牙本质。随机分成6组：对照组(A组),其余5组粘接剂光固化后唾液污染分别进行吹干(B组)、水冲洗后吹干(C组)、直接涂粘接剂并光固化（D组）、吹干后涂一层粘接剂并光固化(E组)、水冲洗后吹干涂一层粘接剂并光固化(F组),用复合树脂（Filtek Z250）分层充填并光固化。37 ℃水浴24 h后测试其微拉伸强度及扫描电镜观察。结果 E组微拉伸强度最高,D组最弱;B组、C组、D组断裂多在混合层底部,树脂突不明显;A组、E组、F组断裂多在混合层中部,树脂突较明显。结论 通用粘接剂光固化后受到唾液污染,牙本质表面清洁后重涂粘接剂是恢复粘接强度必要的手段。     

充填厚度对光固化大块复合树脂充填效果的影响

目的 研究充填厚度对大块复合树脂充填效果的影响.方法 2种大块充填树脂Filtek Bulk Fill Posteri-or(FBF)和Tetric N-Ceram Bulk Fill(TBF)为实验组,2种传统光固化复合树脂Filtek Z100(Z100)和Spec-trum TPH(ST)为对照,测试不同固化厚度...     

钛酸钾晶须增强的复合树脂与两种常用复合树脂的抗弯强度的比较

目的：比较钛酸钾晶须增强的复合树脂与两种常用复合树脂的抗弯强度。方法：以3%硅烷偶联剂处理的钛酸钾晶须按照60%填充量与树脂基质混合,合成热固型和化学固化型两种复合树脂。参照ISO-10477标准,将这两种复合树脂以及临床上常用的两种复合树脂Artglass、Z250制成标准试件,进行三点弯曲测试,并结合显微镜形貌观察,对钛酸钾晶须的增强效果进行比较研究。结果：Z250、化学固化组、热固化组、Artglass的抗弯强度分别是（112.86±13.47）MPa、（102.06±9.36MPa、（123.90±15.90）MPa、（90.60±13.35）MPa。热固化组的抗弯强度显著高于Artglass组。化学固化组的抗弯强度与Z250的抗弯强度相当,低于热固化组。钛酸钾晶须和树脂基质结合良好,能有效阻止微裂纹的形成和扩展。结论：经钛酸钾晶须增强的热固化型复合树脂,其抗弯强度高于其它两种常用的牙用复合树脂。     

三种自粘接树脂水门汀抗压强度的对比测定

目的：对比测定三种临床常用的自粘接树脂水门汀的抗压强度.方法：选用SmartCem2、Unicem、MaxcemElite 3种自粘接树脂水门汀,分别制作10个抗压强度试件,每种树脂水门汀试件分2组,每组5个样本,其中1组37℃水浴24h,另外一组试件37℃水浴30d,万能材料试验机测试其抗压强度值,采用SPSS 13.0软件进行统计分析.结果：①水浴24h组：SmartCem2、Unicem、MaxcemElite的抗压强度分别为280.14±16.40MPa、198.84±19.04MPa、346.11±22.17MPa,由高到低排序为MaxcemElite＞ SmartCem2＞ Unicem,组间两两比较均有统计学差异,P＜0.05;②水浴30d组：SmartCem2的抗压强度高于Unicem和MaxcemElite,P＜0.05,而Unicem和MaxcemElite组间比较无显著性差异,P＞0.05;③水浴30d后,SmartCem2的抗压强度值较水浴24h时明显提高,其它两种树脂水门汀抗压强度均降低.结论：与Unicem和MaxcemElite相比,SmartCem2具有较高的抗压强度,并且固化30d较24h的抗压强度值明显升高.     

Effect of light-activation methods and water storage on the flexural strength of two composite resins and a compomer

The present study evaluated the flexural strength of three composite resins recommended for direct esthetic restorations: a polyacid modified composite (Dyract AP), a unimodal composite resin (Filtek Z250) and a hybrid composite resin (Point 4). The variation factors, apart from the type of composite resin, were the light activation method and the water storage period. The composite resins were light-cured in continuous mode (40 s, 500 mW/cm2) or in ramp mode (0-800 mW/cm2 for 10 s followed by 30 s at 800 mW/cm2) and stored for 24 hours or 30 days in distilled water at 37 degrees C. The data were analyzed by ANOVA and Tukey test for multiple comparisons (alpha = 0.05). The composite resin Z250 presented the highest mean flexural strength (166.74 MPa) and Dyract AP presented the lowest one (129.76 MPa). The storage for 30 days decreased the flexural strength in ramp mode (24 h: 156.64 MPa; 30 days: 135.58 MPa). The light activation method alone did not lead to different flexural strength values.     

Compressive fatigue behavior of dental restorative composites

The purpose of this study was to investigate the compressive fatigue behavior of five dental composites. Cylindrical specimens of 8 mm length and 4 mm diameter were made according to manufacturers' recommendations and stored for two weeks in distilled water at 37 degrees C. Compressive fracture strength was measured, and subsequently fatigue tests at 10 Hz frequency were carried out in distilled water. Compressive fatigue strength was thereby obtained using the staircase method for 10(5) cycles (n = 17) under sinusoidal loading. Acquired data for compressive fracture strength were analyzed using ANOVA and Weibull statistics. Among the dental composites examined, Filtek Z250 exhibited the highest fatigue strength. This seemed to be due to the superior matrix properties coupled with a specific filler type at the highest weight%/volume% ratio. In addition, fracture mechanisms of the composites were examined.     

不同树脂在陈旧性树脂表面微拉伸强度的比较研究

目的：研究不同树脂与陈旧性树脂间的微拉伸强度差异。方法：制备可乐丽菲露 AP-X 树脂样本30例,浸泡于37℃蒸馏水1个月,表面经金刚砂车针研磨后随机分为3组：A 组涂布粘结剂后与可乐丽菲露 AP-X 新鲜树脂粘结;B 组涂布粘结剂后与3M Z250新鲜树脂粘结;C 组涂布粘结剂后与登士柏 TPH 新鲜树脂粘结。制备试件后,在万能材料试验机上测定材料间的微拉伸强度。结果：B 组微拉伸强度最大,C 组次之,A 组最小,3组间有显著性差异。结论：陈旧性树脂缺损的修复可以不要求使用同种树脂,使临床应用简洁化。     

Diametral tensile strength of composite resins submitted to different activation techniques

The aim of this study was to evaluate the diametral tensile strength (DTS) of composite resins submitted to different curing techniques. Four composite resins were tested in this study: Targis (Ivoclar), Solidex (Shofu), Charisma (Heraeus-Kulzer) and Filtek Z250 (3M Espe). Sixty-four cylindrical specimens were prepared and divided into eight groups according to each polymerization technique (n = 8). The indirect composite resins (Targis and Solidex) were polymerized with their respective curing systems (Targis Power and EDG-lux); Charisma and Filtek Z250 were light-cured with conventional polymerization (halogen light) and additionally, with post-curing systems. Specimens were stored in artificial saliva at 37 degrees C for one week. DTS tests were performed in a Universal Testing Machine (0.5 mm/min). The data were statistically analyzed by ANOVA and Duncan tests. The results were (MPa): Z250/EDG-lux: 69.04 feminine; Z250/Targis Power: 68.57 feminine; Z250/conventional polymerization: 60.75b; Charisma/Targis Power: 52.34c; Charisma/conventional polymerization: 49.17c; Charisma/EDG-lux: 47.98c; Solidex: 36.62d; Targis: 32.86d. The results reveal that the post-cured Z250 composite resin showed the highest DTS means. Charisma composite presented no significant differences when activation techniques were compared. Direct composite resins presented higher DTS values than indirect resins.     

EFFECTS OF POLISHING PROCEDURES ON COLOR STABILITY OF COMPOSITE RESINS

The purpose of this study was to investigate the effect of different polishing methods on color stability of posterior, universal and nanohybrid composite resin restorative materials upon exposure to a staining agent. Twenty-five specimens were prepared for each of 5 different composite resins (Filtek Z250, Filtek P60, Quadrant LC, Grandio and Filtek Supreme). Specimens were divided into 5 groups and different polishing procedures, including polishing discs (Pd), polishing discs then diamond polishing paste (PdP), polishing discs then a liquid polishing system (Biscover) (PdB), and combinations of these (PdPB) were used. Unpolished specimens served as the control (C). The specimens were stored for 48 h in a coffee solution. The color of all specimens was measured before and after exposure with a colorimeter, and total color change ∆E*) were calculated. The data were analyzed with a two-way ANOVA and the means were compared by Tukey HSD test (α=0.05). The lowest color difference was observed in the groups PdP and C, while the highest color difference was observed in PdPB, and PdB. When comparing the five different restorative materials, no significant difference was observed between FiltekP60 and FiltekZ250, and these materials demonstrated significantly less color change than Quadrant LC and the nanohybrid materials (Grandio, Filtek Supreme). The posterior (Filtek P60) and universal (Filtek Z250) composite resin restorative materials, which do not contain tetraethyleneglycol dimethacrylate (TEGDMA), were found to be less stainable than the nanohybrid (Grandio, Filtek Supreme) and universal (Quadrant LC) composite resins, which contain TEGDMA. The use of diamond polishing paste after polishing with polishing discs significantly decreased staining when compared to the groups that used polishing discs alone, for all restorative materials tested. The highest color change values were obtained for the specimens that were polished with the Biscover liquid polish system (PdB and PdPB groups).     

Effect of storage media upon the surface micromorphology of resin-based restorative materials

The aim of this study was to evaluate the effect of different storage media upon the surface micromorphology of resin-based restoratives. One resin-modified glass-ionomer (Fuji II LC Improved), one polyacid-modified composite resin (Dyract AP), one microfilled composite resin (Durafill VS), and one hybrid composite resin (Filtek Z250) were tested. For each material, 45 standardized cylindrical specimens were randomly made. After 24 h, samples were finished and polished, and their surface roughness measured to obtain Ra (micro m) baseline values (Bv). Fifteen specimens of each material were then stored at 37 +/- 1 degrees C, for 24 h, either in distilled deionized water or in artificial saliva, or else subjected to a pH-cycling regimen. At the end of 10 days of storage, final readings (Fv) of surface roughness were obtained. The Analysis of Covariance (alpha=0.05), considering the covariate Bv showed a significant interaction between restorative materials and storage media (P value=0.0000). Multiple comparison Tukey's test revealed that the surface roughness of resin-based restoratives subjected to a pH-cycling model was significantly higher compared with both distilled deionized water and artificial saliva. Micromorphological changes were noticed in a situation of acid challenge.     

酸蚀和粘结对陈旧性树脂表面粘结强度的影响

目的：研究不同的表面处理方式对陈旧性树脂与新鲜树脂间粘结强度的影响。方法：制备Z350纳米树脂样本40例,浸泡于37℃蒸馏水2个月,表面经金刚砂车针研磨后随机分为4组：A组（对照组）表面未经处理;B组表面仅涂布粘结剂;12组表面仅37％磷酸酸蚀;D组表面37％磷酸酸蚀后涂粘结剂。上述表面处理后使用新鲜树脂完成样本制备。万能材料试验机上测定材料的微拉伸强度。结果：仅涂粘结剂组微拉伸强度最大,对照组次之,仅酸蚀组最小,酸蚀后涂粘结剂组与对照组间无显著性差异。结论：表面使用粘结剂可明显提高陈旧性树脂与新鲜树脂间的粘结强度。     

Effectiveness of composite resin polymerization using light-emitting diodes (LEDs) or halogen-based light-curing units

The clinical performance of composite resins is greatly influenced by the quality of the light-curing unit used. The aim of this study was to compare the efficiency of a commercial light-emitting diode (LED) with that of a halogen-based light-curing unit by means of dye penetration of a micro hybrid composite resin. The composite resin evaluated was Filtek Z250 (3M Dental). The composite was filled into acrylic moulds that were randomly polymerized for 40 seconds by each of the light-emitting systems: light-emitting diode Ultraled (Dabi Atlante) or halogen light Degulux (Degussa Hülls) curing units. Immediately after polymerization, each specimen was individually immersed in 1 ml of 2% methylene blue solution at 37 degrees C +/- 2 degrees C. After 24 hours, the specimens were rinsed under running distilled water for 1 minute and stored at 37 degrees C +/- 2 degrees C at relative humidity for 24 hours. The composite resins were removed from the moulds and individually triturated before being immersed in new test tubes containing 1 ml of absolute alcohol for 24 hours. The solutions were filtered and centrifuged for 3 minutes at 4,000 rpm and the supernatant was used to determine absorbance in a spectrophotometer at 590 nm. To verify the differences between groups polymerized by LED or halogen light t-test was applied. No significant differences were found between composite resins light-cured by LED or halogen light-curing unit (p > 0.05). The commercially LED-based light-curing unit is as effective to polymerize hybrid composite resins as the halogen-based unit.