不同根管清洗方法对纤维桩粘接强度的影响

目的 通过对根管壁内表面进行不同方式的处理来提高纤维桩的粘接强度.方法 36颗新鲜无龋单根管离体前磨牙桩道预备后随机分为6组,分别进行根管内壁处理.Ⅰ组(对照组)使用生理盐水冲洗,Ⅱ组使用2%氯己定溶液和17%乙二胺四乙酸(EDTA)溶液冲洗,Ⅲ组使用3%过氧化氢溶液、17%EDTA溶液冲洗,Ⅳ组使用5.25%次氯酸钠...     

不同粘接方法对纤维桩在不同根管深度内粘接强度影响的薄片推出实验

[摘要] 目的 较4种粘接方法在不同根管深度内对纤维桩粘接强度的影响。方法 选取28颗离体上颌单根管前牙,常规根管治疗和桩道预备后根据粘接方法随机分为四组。Ⅰ:全酸蚀组(LuxaBond+LuxaCore);Ⅱ:自酸蚀组(iBond+Lux-aCore);Ⅲ:自粘接组(RelyXUnicem);Ⅳ:酸蚀加自粘接组(32%磷酸+RelyXUnicem)对纤维桩进行粘接,之后将粘接有纤维桩的牙切割成1mm厚度的薄片,记录根段部位,将薄片分为根管冠部、中部和尖部三个亚组,进行推出测试后记录薄片推出力值和薄片破坏方式。结果 Ⅰ组和Ⅳ组分别和Ⅱ组、Ⅲ组粘接强度有显著差异(P<0.05),Ⅰ组和Ⅳ组间粘接强度差别无统计学意义(P>0.05);根管冠部粘接强度显著高于尖部(P<0.05)。结论全酸蚀粘接系统粘接强度高于自粘接和自酸蚀系统;自粘接系统加用酸蚀技术可以显著提高纤维桩在根管内的粘接强度;纤维桩在根管内的粘接强度根管冠部大于尖部。     

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。     

纤维桩的表面处理

关于根管桩材料和设计的研究已日益成熟.纤维桩树脂核修复被公认为具有较好的修复效果,现在的研究主要集中在桩核的粘接固位方面.除了对粘接剂的研究外,纤维桩表面处理是增强界面粘接强度的常用方法之一,它可以促进不同成分之间形成化学和机械固位.对纤维桩的表面处理主要为了增强桩在根管内的固位以及桩与树脂核的粘接.本文就此作一综述.     

不同根管牙本质表面处理对树脂水门汀粘接强度的影响

目的 比较不同根管牙本质表面处理对树脂水门汀粘接强度的影响.方法 24颗单根管离体前磨牙在釉牙骨质界处截冠后行根管充填,实验随机分为四组:A组为对照组(无表面处理);B组为冲洗处理组(17％EDTA 10ml和5％NaClO10ml联合冲洗根管各30s);C组为酸蚀处理组(35％磷酸酸蚀根管30s);D组为冲洗+酸蚀处理组(先17％EDTA10ml和5％NaClO10ml联合冲洗根管各30s;后用35％磷酸酸蚀根管30s).用PULPDENT树脂水门汀进行粘接.自凝塑料包埋牙根,切割为1 mm厚的试件,并将其按照根管的深度分为根尖、根中、根冠3组,测试其粘接强度.记录数值并进行统计分析.结果 与A组相比,B组、C组和D组冲洗桩道后,三个区段的根管牙本质与树脂水门汀的粘接强度均明显增加,差异有统计学意义(P＜0.01),其中以D组的粘接强度最高,D组根尖段与其他两段间的粘接强度差异有统计学意义(P＜0.01);三组实验组的根中段和根冠段之间差异没有统计学意义(P＞0.05).无论是对照组还是实验组,根尖段牙本质与树脂水门汀的粘接强度均为最低,根冠段最高,且差异具有统计学意义(P＜0.01).结论 (1)采用冲洗处理、酸蚀处理和冲洗+酸蚀处理根管壁均能增强根管牙本质与树脂水门汀的剪切粘接强度;(2)根管部位对根管牙本质与树脂水门汀的剪切粘接强度有影响.     

不同表面处理的纤维桩微拉伸粘接强度研究

目的:通过微拉伸粘接强度测试法测试在纤维桩表面经过6种不同的处理后与核树脂的粘接强度,探索何种表面处理方法能显著提高纤维桩与核树脂的粘接强度,为临床应用提供参考。方法:将30根石英纤维桩随机分成6组,每组5根。A组纤维桩表面涂布粘接剂,B组涂布硅烷处理剂,吹干后涂粘接剂,C组5%氢氟酸酸蚀30sec,流水冲洗吹干后处理同A组,D组5%氢氟酸酸蚀30sec,流水冲洗吹干后处理同B组,E组24%双氧水处理,后操作同A组,F组24%双氧水处理后操作同B组。在桩周分层固化核树脂,用低速锯沿纤维桩外周平行片切,再垂直粘接面片切成横截面约0.9mm×0.9mm的长方柱状试件,每组15个,用微拉伸粘接强度测试法测试纤维桩与核树脂的微拉伸粘接强度,体视显微镜观察断裂类型。结果:A组微拉伸粘接强度8.78±2.20MPa,B组9.35±1.92MPa,C组15.50±2.87MPa,D组22.98±3.24MPa,E组16.64±2.70MPa,F组24.88±3.9 0MPa。用氢氟酸酸蚀的C组和D组和用双氧水处理的E组和F组的微拉伸粘接强度明显高于A组B组(P<0.05)。用氢氟酸酸蚀后再硅烷化处理的D组比C组、用双氧水处...     

玻璃纤维桩表面不同处理方法对粘接强度的影响

目的 评价表面处理方法对玻璃纤维桩粘接强度的影响.方法 选用MATCHPOST玻璃纤维桩和Relyx玻璃纤维桩各16根,按照表面处理方法随机分为4组:对照组(无表面处理);单独硅烷偶联剂处理组;单独粘接剂处理组;硅烷偶联剂+粘接剂联合处理组,每组每种纤维桩4根.用树脂水门汀将纤维桩粘接就位至圆筒模具,再用自凝塑料包埋.37C蒸馏水水浴24h后从垂直于纤维桩长轴的方向将样本从底部切割2个1 mm薄片.对64个薄片进行微推出测试.所得数据用SPSS19.0统计软件进行分析.结果 MATCHPOST玻璃纤维桩四组中,硅烷偶联剂+粘接剂联合处理组的粘接强度最高,与对照组相比差异具有统计学意义(P＜0.05),与单独粘接剂处理组相比统计学上具有非常显著差异(P＜0.01);其他各组间差异无统计学意义(P＞0.05).Relyx玻璃纤维桩四组中,硅烷偶联剂+粘接剂联合处理组粘接强度最高,但各组间差异无统计学意义(P＞0.05).结论 硅烷偶联剂和粘接剂联合处理后可以增强玻璃纤维桩与树脂水门汀的粘接强度.     

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。     

表面不同处理方法对POPO纤维桩粘接固位力的影响

目的讨论不同表面处理方法对POPO纤维桩粘接固位力的影响。方法取50根POPO纤维桩,根据表面不同处理方法随机分为5组,每组10根。A组：不处理;B组：硅烷化处理60 s;C组：酸蚀处理30 s;D组：酸蚀处理60 s;E组：酸蚀处理120 s。选取45颗离体前磨牙截冠后随机分到5个实验组,树脂粘接纤维桩于根管内,包埋后在电子万能试验机上进行拉力测试。扫描电镜（SEM）观察处理后POPO纤维桩的表面形态。结果不同表面处理方法时纤维桩粘接力差异有统计学意义（P<0.05）,D组的粘接力最大,为（207.33±7.58）N。D组和E组间粘接固位力差异有统计学意义（P=0.027）,D组和C组间粘接固位力差异无统计学意义（P=0.112）。SEM观察处理后纤维桩的表面树脂基质粗糙度及纤维暴露数量有明显改变。结论不同表面处理方法增强了POPO纤维桩的粘接固位力。     

Effects of dentin surface treatments including Er,Cr:YSGG laser irradiation with different intensities on the push-out bond strength of the glass fiber posts to root dentin

Abstract

Objective. Intra-canal post systems are commonly used to restore root-filled teeth. Bond strengths of the posts can be affected by various surface treatments of the post or the dentin. The aim of this study was to evaluate the effects of dentin surface treatments including erbium-chromium; yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation with different intensities on the push-out bond strength of the glass fiber posts to root dentin. Materials and methods. Forty single-rooted human maxillary incisors were filled and post spaces were prepared. After these procedures, the specimens were divided randomly into four groups according to the dentin surface treatments, as follows: (i) untreated surface (control), (ii) 1W Er,Cr:YSGG laser application, (iii) 2W Er,Cr:YSGG laser application and (iv) 3W Er,Cr:YSGG laser application. Then the posts were cemented into the root canals using dual-cured resin cement. Bonded specimens were cut into 1-mm-thick slices and push-out tests were performed using a universal testing device. All specimens were loaded until fracture and the failure modes were evaluated with a stereomicroscope at 32× magnification. Representative specimens were analyzed by scanning electron microscopy. Data were analyzed using a one-way ANOVA, Tukey and Wilcoxon tests. Results. The bond strength values ranged from 3.22–4.68 MPa. There were no statistically significant differences among the groups, regardless of the different levels. The coronal and middle levels of the post space had significantly higher bond strength values compared with the apical level (p < 0.05). Conclusion. Er,Cr:YSGG laser irradiation with different intensities did not increase the bond strength of the fiber posts to the root canal dentin walls.     

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.     

The adhesion between fibre posts and composite resin cores: the evaluation of microtensile bond strength following various surface chemical treatments to posts

AIM: To evaluate the influence of various surface treatments to fibre posts on the microtensile bond strength with different composite resins. METHODOLOGY: A total of 110 fibre posts were randomly divided into five groups, according to the surface pre-treatment performed. Group 1: immersion in 24% H(2)O(2) for 10 min and silanization for 60 s; group 2: immersion in 10% H(2)O(2) for 20 min and silanization for 60 s; group 3: immersion in 4% hydrofluoric acid gel for 60 s and silanization for 60 s; group 4: silanization of the post surface for 60 s and application of the bonding agent G-Bond; group 5: silanization of the post surface for 60 s (control group). After treatment, two posts were randomly selected from each group to evaluate the morphological aspect of the post surface with scanning electron microscopy. The remaining posts in each group were divided into five subgroups of five posts each, which differed in the type of composite resin used for the core build-up. Post-core strength were calculated and the differences among experimental groups were analysed with two-way anova and the Tukey test (alpha = 0.05). RESULTS: The post-core strengths achieved in groups 1 and 2 were significantly higher (P < 0.05), than those of groups 3, 4 and 5. The post-core strength in the control group was significantly lower (P < 0.05) than all other groups. CONCLUSIONS: Hydrogen peroxide and hydrofluoric acid both modified the surface morphology of fibre posts and with silane, significantly enhanced the interfacial strength between them and core materials.     

Bond strengths of five tapered root posts regarding the post surface

The advantage of tapered passive root posts is their homogenous force transmission without creating stress peaks on the root surface because of their anatomical root form. However, their expected retentive strengths are low compared with the other post systems. The objective of this in vitro study was to determine the retentive strengths of five tapered post systems from different manufacturers using tensile tests. For this purpose, all posts were cemented with zinc phosphate cement (Tenet) into the roots of 50 intact anterior teeth according to the manufacturer's instructions for each system. The contact surface area between the root canal wall and the post was taken into account in the calculations in order to obtain comparable results for different post configurations. The highest bond strength values were achieved for the Erlangen post system (10.8 N mm(-2)) and MP Pirec post system (10 N mm(-2)). These values were more than three times those of the Velva-Post (3.2 N mm(-2)) and the Cylindro-Conical system (3.5 N mm(-2)) and five times more than those of the Dr Mooser post system (1.7 N mm(-2)). The bond strength values of the Erlangen post system, Cylindro-Conical system and Dr Mooser post system showed statistically significant differences compared with the other groups. The results of this study indicated that the bond strengths of tapered posts were not only affected by the contact surface but also by the taper angle, shape of the post system, the width of the cement joint, surface roughness of the posts as well as the form of the canal wall. In clinical practice, in case of choosing tapered posts with similar shapes, retention may still vary because of other factors.     

The effect of luting cement thicknesses on the push-out bond strength of the fiber posts

Abstract

Objective. The aim of this study was to evaluate the effect of luting cement thicknesses on the push-out bond strength of the fiber posts. Materials and methods. Sixty human maxillary canine teeth were endodontically treated. Post spaces were prepared and root specimens randomly divided into three groups: Group 1: etch-and-rinse (Variolink II/Exite DSC), Group 2: self-etch (Panavia F2.0/ED primer) and Group 3: self-adhesive (Clearfil SA Cement). Then each group was divided into four sub-groups according to the cement thickness, as follows: Sub-group 1: 0.35 mm, Sub-group 2: 0.25 mm, Sub-group 3: 0.15 mm, and Sub-group 4: 0.05 mm. Three slices of 1 mm thickness were obtained from each root specimen (n = 15). Push-out tests were performed and data was analyzed with two-way ANOVA and Tukey tests. Results. The etch-and-rinse system (Variolink II) had a significantly higher bond strength compared with the other systems (?p < 0.05). The thickest cement group (0.35 mm) had a significantly lower bond strength compared with the 0.15 and 0.05 mm groups in the etch-and-rinse and self-adhesive groups (p < 0.05). In the self-etch group, the cement thicknesses did not significantly affect the bond strength (p > 0.05). Conclusions. The etch-and-rinse system offered better bonding to root dentine than the self-adhesive and self-etch systems. The increases in cement thickness significantly reduced the bond strength of fiber posts to root dentine for both the etch-and-rinse and self-adhesive systems.     

The effect of glass fiber posts and ribbons on the fracture strength of teeth with flared root canals restored using composite resin post and cores

Purpose

This study evaluated the fracture strength and mode of failure of structurally compromised teeth with flared root canals restored using composite resin with four different systems.