不同表面处理方法及根管深度对玻璃纤维桩粘接强度的影响

目的比较4种表面处理方法以及在根管内的深度对纤维桩粘接强度的影响。方法取25颗单根管前磨牙,随机分为5组,常规根管治疗。对25根POPO纤维桩分组进行表面处理:A组(对照组),B组(过氧化氢组),C组(硅烷组),D组(氢氟酸凝胶组),E组(乙醇钠组)。将纤维桩粘接于离体牙根管内并制作薄片试样,根据根管深度将试样分为根上部、根中部、根下部3个亚组,进行微推出实验测试粘接强度。扫描电镜(SEM)下对各组纤维桩的外观形貌进行观察。结果纤维桩粘接强度为B组>D组>E组>A组,各组间差异显著(P<0.05),C组与A组间差异无统计学意义(P>0.05);纤维桩在根管不同深度的粘接强度为:根上部>根中部>根下部(P<0.05);SEM观察显示,经处理后的各组纤维桩表面形貌与对照组相比可见纤维束暴露量增加。结论除硅烷偶联剂外,HF、H2O2、乙醇钠均能显著提高玻璃纤维桩的粘接强度;随着根管深度的增加,纤维桩粘接强度逐渐减小。     

不同黏结方法和不同桩道部位对纤维桩黏结强度的影响

目的:比较不同黏结方法在不同桩道部位对纤维桩黏结剪切强度的影响。方法:选取42颗离体上颌中切牙,根管治疗桩道预备后根据不同的黏结方法随机分为6组,Ⅰ组为全酸蚀黏结剂Luxabond+自黏结树脂水门汀Rely X TM Unicem,Ⅱ组为全酸蚀黏结剂Luxabond+双固化树脂水门汀Luxacore,Ⅲ组为自酸蚀黏结剂Contax+自黏结树脂水门汀 Rely X TM Unicem,Ⅳ组为自酸蚀黏结剂Contax+双固化树脂水门汀Luxacore,Ⅴ组为自黏结树脂水门汀Rely X TM Unicem,Ⅵ组为双固化树脂水门汀Luxacore。纤维桩黏固后行薄片推出实验,并在扫描电镜下观察黏结界面及根管内壁的微观形态。采用SPSS13.0软件包对数据进行统计学分析。结果:不同黏结方法纤维桩的黏结强度差异具有显著性(P<0.05),第Ⅰ组和第Ⅲ组的黏结强度最高。扫描电镜观察,Ⅰ组和Ⅱ组的黏结界面有树脂突形成,黏结界面也更加致密。结论:自黏结树脂水门汀Rely XTM Unicem若配合使用全酸蚀及自酸蚀黏结剂,可显著提高纤维桩的黏结强度。     

Bond strength of fibre glass and carbon fibre posts to the root canal walls using different resin cements

The aim of the study was to evaluate the bond strength of fibre glass and carbon fibre posts in the root canal walls cemented with self-adhesive (RelyX-Unicem) and chemical (Cement-Post) resin cements. Forty maxillary canines were divided into four groups according to the cement and post used and submitted to the push-out test (0.5 mm min(-1)). The data were submitted to statistical analysis (2-way ANOVA, Bonferroni--P<0.05) and fracture analysis by Scanning Electronic Microscopy. Fibre glass presented the best results when cemented with RelyX-Unicem and Cement-Post (P<0.05). RelyX-Unicem presented the highest bond strength values for both posts (P<0.05). Fracture analysis showed predominance of cohesive fracture of post for RelyX-Unicem and adhesive fracture between dentin/cement and mixed for Cement-Post. The bond strength values were significantly affected by the type of post and cement used and the highest values were found for fibre glass posts and RelyX-Unicem.     

Push-out strength of fiber posts depending on the type of root canal filling and resin cement

The purpose of this study was to analyze the push-out strength of two fiber post systems/resin cements (RelyX Unicem/RelyX Fiber Post (RLX) and Variolink II/DT Light SL (VL)) depending on the root canal filling (RF). One hundred sixty extracted human teeth were divided into four groups: gutta-percha/AH Plus (GP), gutta-percha/Guttaflow (GF), pre-existing root canal filling (PRF), and without root canal filling (WRF). After root canal treatment, fiber posts were inserted using either RelyX® or Variolink II®/Excite DSC®. Half of the specimens were thermocycled (TC, 5,000 cycles, 5–55°C). All specimens were subjected to the push-out test (crosshead speed 1 mm/min). Three-way ANOVA showed a significant influence of either the RF or the resin cement/post system (p?p?=?0.001; WRF 16.5?±?6.4 vs 8.0?±?5.0, p?=?0.004) before TC. No differences were found after TC. The fracture mode analysis for VL showed mainly adhesive fractures between post and cement. For RLX, mixed fractures between post and tooth and between tooth and cement were predominantly determined. The adhesion of resin cements/post systems could be dependent on the type of RF. Higher bond strength values were found for the conventional (“etch and rinse”) adhesive than for the “self-adhesive resin cement.”     

Effect of root canal treatments on quartz fiber posts bonding to root dentin

The aim of this study was to evaluate the effect of irrigants and endodontic sealers on fiber post push-out strength in both fatigue cycling and no-cycling conditions. Fifty single-rooted human teeth received five endodontic treatments. The posts were cemented using a flowable composite and a three-steps adhesive. Five specimens from each group were subjected to 2 x 10(6) cycles of 37.5 N. There were 200 sections obtained for the push-out test. Fatigue cycled groups treated with an eugenol-containing sealer showed the lowest push-out strength (p < 0.001). No significant differences were found among no-cycled groups (p = 0.665). The post-cement interface was found to be weaker than the cement-dentin one. However, fatigue cycles increased the occurrence of cement-dentin failures (p = 0.001). The eugenol-containing sealer reduced the bonding of fiber posts when mechanically cycled, thus the use of a resin-based sealer is advisable.     

Flexural properties of fiber reinforced root canal posts.

OBJECTIVES: Fiber-reinforced composite (FRC) root canal posts have been introduced to be used instead of metal alloys and ceramics. The aim of this study was to investigate the flexural properties of different types of FRC posts and compare those values with a novel FRC material for dental applications. METHODS: Seventeen different FRC posts of various brands (Snowpost, Carbopost, Parapost, C-post, Glassix, Carbonite) and diameters, (1.0-2.1 mm) and a continuous unidirectional E-glass FRC polymerized by light activation to a cylindrical form (everStick, diameter 1.5 mm) as a control material were tested. The posts (n=5) were stored at room's humidity or thermocycled (12.000 x, 5 degrees C/55 degrees C) and stored in water for 2 weeks before testing. A three-point bending test (span=10 mm) was used to measure the flexural strength and modulus of FRC post specimens. RESULTS: Analysis of ANOVA revealed that thermocycling, brand of material and diameter of specimen had a significant effect (p<0.001) on the fracture load and flexural strength. The highest flexural strength was obtained with the control material (everStick, 1144.9+/-99.9 MPa). There was a linear relationship between fracture load and diameter of posts for both glass fiber and carbon fiber posts. Thermocycling decreased the flexural modulus of the tested specimens by approximately 10%. Strength and fracture load decreased approximately 18% as a result of thermocycling. SIGNIFICANCE: Considerable variation can be found in the calculated strength values of the studied post brands. Commercial prefabricated FRC posts showed lower flexural properties than an individually polymerised FRC material.     

Influence of root dentin treatment on the push-out bond strength of fiber posts

The aim of the present study was to assess whether different dentin conditioning protocols with different acids [phosphoric acid, ethylene diamine tetra acetic acid (EDTA), and polyacrylic acid (PAA)] influence the bond strength of fiber posts along the radicular depth when luted with self-adhesive resin cement. Twenty single-rooted teeth were randomly divided into four experimental groups (n = 5) according to dentin treatment: Group 1: no treatment; Group 2: etching with 35 % phosphoric acid for 10 s; Group 3: 17 % EDTA application for 60 s; and Group 4: conditioning with 25 % PAA for 30 s. RelyX Fiber Posts were luted with the self-adhesive resin cement RelyX Unicem 2 Automix (3M ESPE). Roots were transversally sectioned into nine 1-mm thick specimens, three corresponding to each root third and a push-out test was performed. Data were analyzed by two-way ANOVA and Tukey test (p < 0.05). Failure mode was determined and specimens with representative failures for each group were observed under scanning electron microscopy. According to the results, dentin treatment influenced the bond strength (p < 0.001), whereas the root third did not (p > 0.05). Fiber posts luted after treating dentin with phosphoric acid, and PAA exhibited the highest push-out bond strength values, while the lowest were obtained after EDTA application. Intermediate results were obtained when dentin was not conditioned. In conclusion, the bond strength of the self-adhesive resin cement RelyX Unicem 2 improves when root dentin is treated with 35 % phosphoric acid or 25 % PAA, before fiber posts luting irrespective of the root depth.     

Carbon fiber reinforced root canal posts Mechanical and cytotoxic properties

The aim of this study was to compare the mechanical properties of a prefabricated root canal post made of carbon fiber reinforced composites (CFRC) with metal posts and to assess the cytotoxic effects elicited. Flexural modulus and ultimate flexural strength was determined by 3 point loading after CRFC posts had been stored either dry or in water. The bending test was carried out with and without preceding thermocycling of the CFRC posts. The cytotoxicity was evaluated by an agar overlay method after dry and wet storage. The values of flexural modulus and ultimate flexural strength were for dry stored CFRC post 82±6 GPa and 1154±65 MPa respectively. The flexural values decreased significantly after water storage and after thermocycling. No cytotoxic effects were observed adjacent to any CFRC post. Although fiber reinforced composites may have the potential to replace metals in many clinical situations, additional research is needed to ensure a satisfying life-span.     

4种纤维桩X线阻射性的对比研究

目的：对比几种常用纤维桩的X线阻射性是否有差别。方法???选择常用的3种纤维桩,即RelyX??Fiber?Post （RelyX）,PARAPOST??FIBER?LUX（Parapost）和D.T.?Light-Post?Illusion?X-RO（DT）和新型的阻射性纤维桩Macro-Lock?Illusion?X-RO（ML）。收集20颗离体前磨牙,随机分成4组（n=5）,按照厂家说明预备桩道,用Parabond和ParaCore系统粘接4种纤维桩;另外将纤维桩横切制备成厚度为2?mm的试件,制作标准铝楔,然后拍摄X线片评价其阻射性,并用电子显微镜观察纤维桩断面。结果???ML组纤维桩的X线阻射性明显高于其他3组（P相似文献   

The adhesion between fiber posts and root canal walls: comparison between microtensile and push-out bond strength measurements

Aim of the study was to compare the trimming and non-trimming variants of the microtensile technique with the 'micro' push-out test in the ability to measure accurately the bond strength of fiber posts luted inside root canals. In 15 endodontically treated teeth (Group A), fiber posts were cemented with Excite DSC in combination with Variolink II (Ivoclar-Vivadent). In 15 roots RelyX Unicem (3M-ESPE) was used for fiber post luting (Group B). Within each group, the bond strength of cemented fiber posts was assessed with the trimming and non-trimming microtensile technique, as well as with the push-out test. The great number of premature failures (16.9% in Group A, 27.5% in Group B) and the finding of high standard deviation values make questionable the reliability of the trimming microtensile technique. With the non-trimming microtensile technique, only five sticks were obtained from a total of six roots. The remaining specimens failed prematurely during the cutting phase. With the push-out test no premature failure occurred, the variability of the data distribution was acceptable, and regional differences in bond strength among root levels could be assessed. Relatively low values of bond strength were, in general, recorded for luted fiber posts. In conclusion, when measuring the bond strength of luted fiber posts, the push-out test appears to be more dependable than the microtensile technique.     

Effect of crosslinkers on bond strength stability of fiber posts to root canal dentin and in situ proteolytic activity

Statement of problem

Improved stability of the adhesive interface can be obtained using crosslinkers. However, research on the use of crosslinkers in root dentin is lacking.

不同根管封闭剂及清洗方法对纤维桩粘接强度的影响

目的 研究不同根管封闭剂和清洗方法对纤维桩粘接强度的影响,探讨二者对纤维桩粘接强度是否存在交互影响作用。方法 48颗离体下颌前磨牙行完善根管治疗后,根据根管封闭剂随机分为两组,A组采用Endofil封闭剂（丁香酚类）,B组采用AH-plus封闭剂（树脂类）。桩道预备后每组再根据根管清洗方法分为3个亚组（每组8颗）：A1、B1组采用0.9%NaCl溶液清洗;A2、B2组采用17%乙二胺四乙酸（EDTA）+5.25%NaClO+0.9%NaCl溶液清洗;A3、B3组采用17%EDTA+5.25%NaClO+0.9%NaCl溶液+超声清洗。采用RelyX^TMUnicem树脂粘接剂黏固纤维桩1周后,行薄片推出实验。对结果进行三因素方差分析及Turkey检验。采用扫描电子显微镜（SEM）观察根管内壁的超微形态。结果 6组的纤维桩粘接强度分别为A1组（7.96±2.23） MPa,A2组（9.95±2.89）MPa,A3组（18.88±3.69）MPa,B1组（11.41±3.71）MPa,B2组（14.00±4.04）MPa,B3组（19.14±3.27）MPa。三因素方差分析表明：不同的根管封闭剂与清洗方法具有交互作用（P<0.05）; B1组粘接强度大于A1组,B2组大于A2组（P<0.05）,B3与A3组无明显差异（P>0.05）。SEM显示A3、B3组的根管内壁玷污层最少,牙本质小管完全开放。结论 采用0.9%NaCl溶液、17%EDTA+5.25%NaClO+0.9%NaCl溶液清洗根管时,使用丁香酚类根管封闭剂较树脂类根管封闭剂的纤维桩粘接强度降低;超声联合17%EDTA+5.25%NaClO+0.9%NaCl溶液清洗根管,两种根管封闭剂对纤维桩粘接强度的影响无明显差异。     

离体牙经不同根管封闭剂充填后纤维桩剪切粘结强度的对比研究

目的:研究不同根管封闭剂对两种纤维桩固位力的影响。方法:24颗离体上颌中切牙,截冠、预备根管,按根管封闭材料及纤维桩不同均分为4组。C-RP组:Cortisomol丁香酚类封闭剂,Rebilda Post纤维桩;C-ML组:Cortisomol封闭剂,Mac-rolockTM Post纤维桩;G-RP组:Guttaflow非丁香酚类封闭剂,Rebilda Post纤维桩;G-ML组:Guttaflow封闭剂,MacrolockTM Post纤维桩。自酸蚀粘结剂将纤维桩粘固,牙根切成1.5 mm薄片,行薄片推出实验,并观察断裂模式。扫描电镜观察粘结界面的显微结构。结果:C-RP、C-ML、G-RP、G-ML 4组剪切粘结强度(MPa)分别为5.89±2.89、7.46±2.71、7.66±3.00、9.24±3.03,C-RP粘结强度最低(P<0.05)。牙根颈、中、根尖部的剪切粘结强度依次降低(P<0.01)。扫描电镜观察:相比根尖部,颈部有明显树脂突;使用Guttaflow封闭剂组混合层厚度以及树脂突数目、长度优于使用Cortisomol组。结论:使用丁香酚类根管封闭会降低纤维桩剪切粘结强度;纤维桩修复后根尖部的粘结强度有待增强。     

离体牙经不同根管封闭剂充填后纤维桩剪切粘结强度的对比研究

目的：研究不同根管封闭剂对两种纤维桩固位力的影响。方法：24颗离体上颌中切牙,截冠、预备根管,按根管封闭材料及纤维桩不同均分为4组。C-RP组：Cortisomol丁香酚类封闭剂,Rebilda Post纤维桩;C-ML组：Cortisomol封闭剂,Mac-rolockTM Post纤维桩;G-RP组：Guttaflow非丁香酚类封闭剂,Rebilda Post纤维桩;G-ML组：Guttaflow封闭剂,MacrolockTM Post纤维桩。自酸蚀粘结剂将纤维桩粘固,牙根切成1.5 mm薄片,行薄片推出实验,并观察断裂模式。扫描电镜观察粘结界面的显微结构。结果：C-RP、C-ML、G-RP、G-ML 4组剪切粘结强度（MPa）分别为5.89±2.89、7.46±2.71、7.66±3.00、9.24±3.03,C-RP粘结强度最低（P〈0.05）。牙根颈、中、根尖部的剪切粘结强度依次降低（P〈0.01）。扫描电镜观察：相比根尖部,颈部有明显树脂突;使用Guttaflow封闭剂组混合层厚度以及树脂突数目、长度优于使用Cortisomol组。结论：使用丁香酚类根管封闭会降低纤维桩剪切粘结强度;纤维桩修复后根尖部的粘结强度有待增强。     

不同纤维桩与根管不同粘结处理修复后剪切粘结强度对比研究

目的比较四种不同粘结系统处理后不同纤维桩与根管各部的剪切粘结强度。方法45颗完整离体尖牙于釉牙骨质界冠方2 mm处截冠、根管治疗后随机分9组,使用两种纤维桩和四种粘结树脂及配套粘结剂修复:DTlight纤维桩,玻璃纤维桩,3MUnicem Rely XTM,DCcore Automix,Dual-link,Luxacore Z Automix。包埋后切不同根管段行剪切粘结实验并观察界面断裂类型,记录数据并统计分析。结果剪切粘结强度(MPa)为:D.T.light组:Luxacore Z Automix1(10.15±0.67)Mpa,DC coreAutomix(7.72±2.03)Mpa,Luxacore Z Automix2(7.25±0.71)Mpa,3MUnicem Rely XTM(6.61±1.82)Mpa,Dual-link(5.35±1.42)Mpa;玻璃纤维桩组:Luxacore Z Automix1(14.60±1.79)Mpa,3MUnicem Rely XTM(11.12±1.95)Mpa,DC core Automix(10.15±1.29)Mpa,Dual-link(8.55±1.40)Mpa。体视显微镜观察显示绝大部分样本的断裂方式都是粘结面型断裂。结论纤维桩修复的剪切粘结强度与纤维桩材料、粘结部位及粘结材料密切相关。