Effect of Light‐Emitting Diode (LED) Curing Modes on Resin/Dentin Bond Strength

Purpose: This study aimed to compare the effect of three curing modes of a high‐powered curing‐light source on the shear bond strength and marginal gap of light‐ and dual‐cured adhesive resin cements to dentin. Materials and Methods: Twelve freshly extracted intact human mandibular molars were selected for this study and stored in the saline solution. Three of the axial surfaces of the teeth were prepared to obtain flat dentinal surfaces. Thirty‐six ceramic disks (4‐mm diameter, 2‐ mm thick) were constructed from a pressable glass‐ceramic (Vision). The discs were etched with hydrofluoric acid and primed, and then divided into two equal groups, groups I and II (n = 18 each). Two adhesive systems were used following manufacturer's instructions. The discs of group I were bonded to the conditioned dentin surface using adhesive resin (Rely X Veneer), and group II discs were bonded to dentin using Rely X ARC. For each group, the resin was cured using three modes (fast, ramp, pulse). Interfacial gap at the dentin/resin interface was measured at eight predetermined sites for each specimen using a stereomicroscope, and shear bond strength of the bonded specimens was carried out using a universal testing machine. Results: Ramp‐cured specimens recorded significantly higher mean shear bond strengths for both dual‐ and light‐polymerized resins than those with fast and pulse modes. Moreover, fewer interfacial gaps were found at the resin/dentin interface in association with ramp cure modes of both resins. Most failures were adhesive failures at the dentin–resin luting agent (RLA) interface in specimens polymerized using high‐powered LED fast or pulse modes, while a cohesive failure pattern within the resin was associated with the ramp‐curing mode. Conclusion: Within the limitations of this study, the shear bond strength of an RLA to dentin was found to be enhanced with light‐ or dual‐polymerized adhesive resin using an LED light in ramp mode, whereas shear bond strength was significantly lower when polymerized using LED in fast or pulse modes.     

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。     

不同树脂水门汀和瓷表面处理对玻璃陶瓷粘结强度的影响

目的：评价4种不同的树脂水门汀以及2种不同的瓷表面处理方法对玻璃陶瓷粘结强度的影响。方法：选用IPse．Max Press热压铸瓷制作直径分别为5mm和4mm,高2mm的圆柱形瓷片。经打磨抛光后分为喇大组：（1）4％氢氟酸酸蚀40sec,（2）4％氢氟酸酸蚀40sec＋硅烷化处理1min。各组内分别选用VariolinkII,Multflink Sprint,RelyX Unicem,BisCem将大小瓷片成对粘固。再分别经37℃水储24h,以及水储后冷热循环5000次测定剪切强度,并用电镜观察瓷片表面形态。结果：硅烷化处理能明显提高粘结强度。经HF＋硅烷处理后Multflink Sprint（31．7±4．5MPa）,BisCem（29．2±4．4MPa）和RelyX Unicem（28．1±5．5MPa）3组显示出较VafiolinkII（21．8±4．2MPa）高的粘结强度。冷热循环后除硅烷处理且用VariolinkII和RelyX Unicem粘固的实验组外,其余各组粘结强度均显著下降。结论：4种树脂水门汀与经HF和硅烷联合处理的玻璃陶瓷问能达到理想的粘结强度。     

Push-out bond strengths of endodontic posts bonded with different resin-based luting cements

PURPOSE: To compare the push-out bond strengths of endodontic posts bonded with different resin-based luting cements and to verify that bond strengths did not vary with cement thickness. METHODS: 48 root canals were shaped using 6% NiTi rotary files, obturated with gutta-percha and AH Plus sealer and prepared for post cementation using Panavia F, Parapost cement, SuperBond and Unicem Rely X. All roots were sectioned into 0.7 mm thick slices and digital photographs of each slice were analyzed using Scion Image to measure the surface area of the luting cement. The root slices were stressed to failure at 1 mm/minute using a push-out test. Push-out strength was calculated as the force at failure divided by the bonded surface area. Least squares linear regression analysis was used to assess the effect of cement thickness on bond strength. Fractured specimens were further observed under the SEM. RESULTS: Mean push-out bond strengths were: Panavia F (8.8 +/- 3.6 MPa), Parapost cement (9.1 +/- 4.4 MPa) SuperBond (14.6 +/- 2.9 MPa) and Rely X Unicem (12.4 +/- 3.3 MPa). The Panavia F and the Parapost cement were not significantly different from each other, but both were significantly lower (P < or = 0.05) than SuperBond and Rely X Unicem. Although there were large variations in cement thickness, the cementation of fiber posts with thicker cement layers did not affect the performance of the adhesive luting cements applied to root canal dentin.     

3种树脂水门汀对CAD/CAM全瓷-牙本质剪切强度的比较

目的:评价3种树脂水门汀对CAD/CAM全瓷-牙本质剪切强度的影响。方法:选取新鲜拔除的人磨牙30颗,制备牙本质黏结面,随机分为3组(n=10),分别选用全酸蚀树脂水门汀RelyX ARC、自酸蚀树脂水门汀Clearfil DCBond和自黏结树脂水门汀RelyX Unicem对CAD/CAM硅酸锂玻璃全瓷进行黏结,测试3种树脂水门汀对CAD/CAM全瓷-牙本质的剪切强度,并通过立体显微镜观察牙本质的黏结界面。采用SPSS11.0软件包对数据进行统计学分析。结果:RelyX ARC组的剪切强度为(15.90±6.15)MPa,Clearfil DC Bond组的剪切强度为(14.41±5.07)MPa,而RelyXUnicem组的剪切强度为(23.29±7.39)MPa,与前2组相比有显著性差异(P<0.05)。立体显微镜观察显示,3组黏结断面均位于牙本质与树脂水门汀之间。结论:自酸蚀树脂水门汀及自黏结树脂水门汀与CAD/CAM硅酸锂玻璃陶瓷修复体的黏结强度不低于传统全酸蚀树脂水门汀,且临床操作简便,为临床全瓷黏结提供了更多便利与选择。     

不同树脂粘固剂对瓷与牙本质粘接强度的比较研究

目的 评价不同种类树脂粘固剂与瓷-牙本质粘接强度的差异,以期为临床提供参考.方法选取无龋坏青年人前磨牙制备牙本质粘接面,铸造直径为3 mm、高为3 mm的圆柱状瓷块(IPS e.max Press)80个,分为A、B、C、D、E 5组.分别选用树脂粘固剂A(Variolink Ⅱ)、B(MultilinkAutomix)、C(Multilink Sprint)、D(Rely X Unicem)和E(BisCem)将瓷块粘固于牙本质粘接面上,每组制成16个试样.37℃水储24 h后每组8个试样直接测试剪切粘接强度,另8个试样进行5000次冷热循环后测试粘接强度,扫描电镜观察粘接面形态.对同种粘固剂冷热循环前后的粘接强度进行双样本t检验.结果冷热循环前A组粘接强度[(22.3±3.9)MPa]最大,B组[(18.1±3.5)MPa]次之,再次为D组[(14.1±2.3)MPa]和E组[(11.7±4.2)MPa],C组[(11.3±3.6)MPa]最小.冷热循环后A组粘接强度[(17.8±2.3)MPa]仍最大,B组[(14.4±3.5)MPa]和D组[(13.2±2.5)MPa]次之,再次为E组[(8.9±3.2)MPa],C组[(7.0±2.4)MPa]最小.与冷热循环前相比,冷热循环后A、B、C 3组粘接强度均下降,差异有统计学意义(P<0.05);D组和E组粘接强度下降不明显(P>0.05).结论以全酸蚀粘接技术为基础的树脂粘固剂的粘接强度大于以自酸蚀粘接技术为基础的树脂粘固剂和自粘接型树脂粘固剂.     

Microleakage and marginal gap of adhesive cements for noble alloy full cast crowns

Very limited comparative information about the microleakage in noble alloy full cast crowns luted with different types of adhesive resin cements is available. The purpose of this study was to evaluate the microleakage and marginal gap of two self-adhesive resin cements with that of other types of adhesive luting cements for noble alloy full cast crowns. Fifty noncarious human premolars and molars were prepared in a standardized manner for full cast crown restorations. Crowns were made from a noble alloy using a standardized technique and randomly cemented with five cementing agents as follows: 1) GC Fuji Plus resin-modified glass ionomer cement, 2) Panavia F 2.0 resin cement, 3) Multilink Sprint self-adhesive resin cement, 4), Rely X Unicem self-adhesive resin cement with pretreatment, and 5) Rely X Unicem with no pretreatment. The specimens were stored in distilled water at 37°C for two weeks and then subjected to thermocycling. They were then placed in a silver nitrate solution, vertically cut in a mesiodistal direction and evaluated for microleakage and marginal gap using a stereomicroscope. Data were analyzed using a nonparametric Kruskal-Wallis test followed by Dunn multiple range test at a p<0.05 level of significance. The Rely X Unicem (with or with no pretreatment) exhibited the smallest degree of microleakage at both tooth-cement and cement-crown interfaces. The greatest amount of microleakage was found for Panavia F 2.0 resin cement followed by GC Fuji Plus at both interfaces. No statistically significant difference in the marginal gap values was found between the cementing agents evaluated (p>0.05). The self-adhesive resin cements provided a much better marginal seal for the noble alloy full cast crowns compared with the resin-modified glass ionomer or dual-cured resin-based cements.     

3种树脂粘接水门汀与铸造纯钛粘接强度研究

目的：研究3种复合树脂粘固剂与铸造纯钛的粘接强度。方法：用牙科铸钛的方法制作直径分别为4mm和5mm的钛棒,切割成长度为4mm的小钛片。2种规格的钛片配对粘接面用400～1200目碳化硅砂纸在流水下打磨抛光,使之呈均匀一致的平面。50μm氧化铝喷砂,另一组表面不喷砂作为对照,分别使用Super-BondC＆B、Panavia F、Rely X Unicem 3种复合树脂粘固剂粘接。扫描电镜观察喷砂前后铸造纯钛的表面形态。复合树脂粘接剂固化后经37℃恒温水浴24h以及5000次5～55℃冷热循环,测试剪切强度。用SAS的ANOVA过程对各组数据进行分析。结果：喷砂前后纯钛与Panavia F的剪切强度最高,分别为（26.62±3.40）MPa、（23.71±5.28）MPa;5000次冷热循环后,喷砂组的铸造纯钛与Panavia F的剪切强度最高（27.12±8.68）MPa;未喷砂的铸造纯钛与Super-Bond C＆B、Rely X Unicem的粘接强度最低,并且有12.5%的脱落率。结论：本实验结果表明喷砂可以提高Super-Bond C＆B、Panavia F、Rely X Unicem的粘结力和粘结耐久力。不喷砂时,Panavia F与铸造纯钛之间能获得较高的粘接强度和良好的粘接耐久性,喷砂以后优势不再明显。     

Bond strength and interfacial micromorphology of etch-and-rinse and self-adhesive resin cements to dentin

Purpose: To evaluate the microtensile bond strength and interfacial micromorphology of indirect composite restorations to dentin using three commercial resin cements after 24 hours and 30 days of water storage. Materials and Methods: The medium dentin of third human molars was exposed (N = 30, n = 10 per group). Three commercial resin cements were used to cement indirect resin composite restorations to dentin: the auto‐cured C&B Cement/All Bond 2, the dual‐cured RelyX ARC/Adper Single Bond 2, and the self‐adhesive dual‐cured RelyX Unicem. Teeth were sectioned after water storage at 37°C (24 hours and 30 days) to obtain beams with a bonded area of 0.8 mm². The specimens were tested in a universal testing machine at a 0.5 mm/min crosshead speed. Scanning electron microscopic fractographic and interfacial micromorphology analyses were performed. Data were analyzed using two‐way ANOVA and Tukey′s test (α= 0.05). Results: Mean bond strength (MPa) after 24 hours: C&B Cement 19.5 ± 3.8, RelyX ARC 40.8 ± 9.4, RelyX Unicem 31.3 ± 7.4; after 30 days: C&B Cement 24.5 ± 5.1, RelyX ARC 44.2 ± 8.5, RelyX Unicem 28.3 ± 7.1. The mean bond strengths of both dual‐cure cements were significantly higher than that obtained with C&B Cement after 24 hours. A significant increase in the bond strength of C&B Cement was verified after 30 days, reaching values statistically equivalent to those produced by RelyX Unicem and RelyX ARC. The self‐adhesive cement preserved the same level of bond strength after 30 days. Fractographic analysis revealed a prevalence of cohesive fractures in the hybrid layer for C&B Cement, mixed (cohesive in the cement, hybrid layer, and adhesive) for RelyX ARC, and cohesive in the cement for RelyX Unicem. No distinguishable hybrid layer or resin tags were observed in the interaction of RelyX Unicem with dentin. Conclusions: The particular interaction of each cement with dentin results in specific bond strength and failure patterns that varied among groups in both evaluation times. Even though the self‐adhesive cement tested exhibited no authentic hybrid layer, it was able to promote reliable adhesion with the underlying dentin.     

放疗对全瓷-牙本质粘接剪切强度的影响

目的 探讨放射线对于全瓷-牙本质粘接剪切强度的影响.方法 36颗人离体磨牙以垂直于牙长轴方向分为近远中两部分获得72个样本,热压铸造法制作72个直径4 mm,高1.5 mm的圆柱形IPS e.max试件.样本按是否给予放射线随机分为放射后粘接组、粘接后放射组和空白对照组3个实验组,放射剂量为60 Gy.每个组再分为2个亚组(n=12),分别用Rely X Unicem(3M ESPE)、Panavia F(Kuraray)进行全瓷-牙本质粘接.对所有样本进行剪切测试,用SPSS 16.0软件对结果进行双因素方差分析,并在体视显微镜下观察粘接失败界面破坏模式.结果 放射后粘接组的剪切强度明显低于空白对照组(P<0.05),粘接后放射组与空白对照组之间并无统计学差异,同时发现Panavia F的粘接效果优于Rely X Unicern(P< 0.05),且破坏界面多发生在牙本质与树脂粘接剂之间.结论 对放疗后的牙体缺损进行全瓷修复时,放射线可能对全瓷-牙本质粘接有不利影响.     

酸蚀对自黏结树脂水门汀与牙本质黏结强度的影响

目的:评价酸蚀预处理对自黏结树脂水门汀Unicem、G-Cem、Clearfil SA Cement、BisCem与牙本质微拉伸黏结强度的影响。方法:选用人无龋离体第三恒磨牙32颗,用低速切片机将选用磨牙冠1/4处沿垂直于牙体长轴方向切开,暴露牙本质。实验组在牙本质表面涂布37%磷酸,冲洗、吹干,对照组不做处理。然后将各组与直径为5 mm、高为4 mm的树脂块分别用 Unicem、G-Cem、Clearfil SA Cement、BisCem进行黏结。水浴24 h后,用低速切片机将样本切割成约1 mm×1 mm×8 mm条状,再进行微拉伸测试,并通过扫描电镜观察黏结界面。采用SPSS16.0软件包对数据进行统计学分析。结果:Unicem组（12.9±3.2） MPa、G-Cem组（11.7±2.6） MPa及Clearfil SA Cement组（10.9±2.3） MPa与牙本质的微拉伸黏结强度显著高于BisCem组（6.8±2.4） MPa（P<0.05）。酸蚀预处理后,Unicem组（9.2±2.5） MPa、G-Cem组（6.1±2.3） MPa及Clearfil SA Cement组（4.8±1.7） MPa黏结强度显著降低（P<0.05）,而BisCem组（7.1±2.9） MPa黏结强度无显著差异。结论:牙本质的表面酸蚀预处理降低了自黏结树脂水门汀G-Cem、Clearfil SA Cement及Unicem 的牙本质黏结强度,但对BisCem的牙本质黏结强度无显著影响。     

Shear bond strength of "one bottle" dentin adhesives

STATEMENT OF PROBLEM: Several 1-bottle dentin adhesive resins have been introduced to the market; however, their shear bond strength still requires further investigation. PURPOSE: This study was designed to evaluate the shear bond strength of five 1-bottle fifth generation dentin adhesive resin materials. MATERIAL AND METHODS: Bond 1, Single Bond, One-Step, Prime & Bond 2.1, and Tenure Quick with fluoride were evaluated. Tenure All-Surface Bonding System, a fourth generation dentin adhesive resin, was used as the control group. Twelve specimens were prepared from each material, and the shear bond strength was measured by using a universal testing machine at a crosshead speed of 0.5 mm/min. Fracture patterns were studied with the use of light and SEM. The results were analyzed with the use of ANOVA. RESULTS: The mean shear bond strength for each resin was as follows: Bond 1: 18.36 +/- 3.19 MPa; Single Bond: 16.22 +/- 2.11 MPa; One-Step: 22.51 +/- 3.69 MPa; Prime & Bond: 16. 64 +/- 3.66 MPa; Tenure Quick: 16.43 +/- 3.2 MPa; and Tenure All-Surface Bonding System: 15.06 +/- 3.5 MPa. The shear bond strength values of One-Step dentin adhesive resin showed significant differences compared with the other 5 groups (P<.001). No significant differences were seen between the control group and the other four 1-bottle dentin adhesive resins (0.25 > P>.1). Eighty percent or more of the specimens for each adhesive failed at the dentin/adhesive interface. An exception was Tenure All-Surface Bonding System in which all specimens failed at the dentin/adhesive interface. CONCLUSION: The 1-bottle systems tested bond to dentin with a strength similar to that of the control group. In addition, the shear bond strengths of 4 of the 1-bottle systems tested were not significantly different.     

Tensile bond strength of dual curing resin-based cements to commercially pure titanium.

OBJECTIVES: The aim of this study was to evaluate the tensile bond strength of dual curing luting resin cements to commercially pure titanium at 10 min and 24h after removal of the oxide layer. METHODS: One hundred and twenty titanium discs were obtained by casting and polishing with silicon carbide papers. The titanium discs were sandblasted with 50 microm aluminum oxide, ultrasonic cleaned and bonded in pairs with the resin-based cements Panavia F and Rely X ARC at 10 min and 24h after the sandblasting. The tensile test was performed with a crosshead speed of 0.5mm/min in an Instron Universal testing machine. RESULTS: The Rely X ARC reached the highest tensile strength value at 24h after sandblasting (18.27 MPa), but there was no statistically significant difference between the two dual curing resin cements for both times tested. All specimens showed a mixture of cohesive fracture in the resin cement and adhesive failure. However, the predominant failure mode for Panavia F was cohesive in resin cement, and the Rely X ARC exhibited a greater proportion of specimens with adhesive failure between the alloy and resin luting cement at 10 min and 24h. SIGNIFICANCE: Both cements had, statistically, the same tensile bond strength. But in the fracture mode analysis, the adhesive predominant fracture mode of Rely X ARC cement indicates a premature clinical adhesive failure. On the other hand, the cohesive predominant fracture mode of Panavia F indicates a longer clinical adhesive bond with titanium.     

碳纤维桩与几种桩的剪切抗折强度和剪切粘结强度的测定比较

目的　比较碳纤维桩、IPS Empress 2全瓷桩 (不含二氧化锆芯 )和二氧化锆全瓷桩、铸造镍铬合金桩及牙本质的剪切抗折强度 ;测定碳纤维桩、IPS Empress 2全瓷桩、铸造镍铬合金桩与人离体牙的剪切粘结强度 ,供临床参考应用。方法　碳纤维桩、IPS Empress 2全瓷桩、二氧化锆全瓷桩、铸造镍铬合金桩及牙本质各制作标准圆柱形试件 3个 ,用DCS5 0 0 0力学实验机测试其剪切抗折强度。碳纤维桩、IPS Empress 2全瓷桩和铸造镍铬合金桩各制作标准圆柱形试件 5个 ,用玻璃离子水门汀粘结在根管预备深度 3 0mm、预备直径 2 0mm的天然牙根内 ,用DCS5 0 0 0力学实验机测试其剪切粘结强度。结果　每种试件的平均剪切抗折强度 (MPa) :碳纤维桩 (199)、二氧化锆全瓷桩(193)、镍铬合金桩 (2 10 )的剪切抗折强度明显高于牙本质 (10 0 )和IPS Empress 2全瓷桩 (10 9) ,其间差异有显著性 (P <0 0 5 )。碳纤维桩、镍铬合金桩及二氧化锆全瓷桩之间的剪切抗折强度相近 ,差异无显著性 (P <0 0 5 )。剪切粘结强度 (MPa) :碳纤维桩 (2 4 )、镍铬合金桩 (3 8) ,IPS Empress 2全瓷桩未与水门汀分离前断裂。前 2种试件之间差异无显著性 (P >0 0 5 )。结论　碳纤维桩具有与二氧化锆全瓷桩、铸造镍铬合金桩相近的剪切抗折强度 ,其剪     

Comparison of the bond strength of laser-sintered and cast base metal dental alloys to porcelain

OBJECTIVE: The purpose of this study was to compare shear bond strengths of cast Ni-Cr and Co-Cr alloys and the laser-sintered Co-Cr alloy to dental porcelain. METHODS: Dental porcelain was applied on two cast and one laser-sintered base metal alloy. Ten specimens were prepared for each group for bond strength comparison. ANOVA followed by Tukey HSD multiple comparison test (alpha=0.05) was used for statistical analysis. Fractured specimens were observed with a stereomicroscope to classify the type of failure after shear bond testing. RESULTS: While the mean shear bond strength was highest for the cast Ni-Cr metal-ceramic specimens (81.6+/-14.6MPa), the bond strength was not significantly different (P>0.05) from that for the cast Co-Cr metal-ceramic specimens (72.9+/-14.3MPa) and the laser-sintered Co-Cr metal-ceramic specimens (67.0+/-14.9MPa). All metal-ceramic specimens prepared from cast Ni-Cr and Co-Cr alloys exhibit a mixed mode of cohesive and adhesive failure, whereas five of the metal-ceramic specimens prepared from the laser-sintered Co-Cr alloy exhibited the mixed failure mode and five specimens exhibited adhesive failure in the porcelain. CONCLUSIONS: The new laser-sintering technique for Co-Cr alloy appears promising for dental applications, but additional studies of properties of the laser-sintered alloy and fit of castings prepared by this new technique are needed before its acceptance into dental laboratory practice. SIGNIFICANCE: Laser sintering of Co-Cr alloy seems to be an alternative technique to conventional casting of dental alloys for porcelain fused to metal restorations.     

Evaluation of a 4-META Adhesive Cement

This study investigated the shear bond strength of a new 4-META adhesive cement (C & B-Metabond) to dentin and Ni-Cr-Be alloy (Rexillium III). Fifteen human molar teeth had dentin bonding sites prepared by grinding away the enamel on a water-cooled abrasive wheel to a 600 grit. Fifteen metal alloy specimens were cast, ground to a 600 grit, and air abraded with 50 micron alumina. The 4-META cement was applied to the dentin and metal in accordance with the manufacturer's instructions. After 24 hours in water at 37° C, the shear bond strengths were recorded. The mean bond strength to dentin and the metal alloy was 20.1 megapascals.     

Nd: YAG激光对3种树脂水门汀与牙本质粘接强度的影响

目的观察Nd: YAG激光照射前后树脂水门汀-牙本质粘接界面的微观形貌特征,评价Nd: YAG激光对3种树脂水门汀与牙本质间粘接强度的影响。方法选择人离体前磨牙30颗,分为颊、舌两部分,将试件随机分为激光组和对照组。激光组以0.8 W、10 Hz脉冲Nd: YAG激光作用于牙本质表面25 s,联合3种树脂水门汀RelyX ARC、Panavia F和RelyX Unicem充填;对照组直接使用树脂水门汀充填。然后测试剪切强度,在根管显微镜下观察断裂模式并分类。另选人离体前磨牙6颗,按照标准的牙本质粘接面预备后,使用Nd: YAG激光照射3颗牙牙本质表面,并联合充填不同的树脂水门汀,用扫描电镜观察Nd: YAG激光照射前后树脂水门汀-牙本质界面的微观形貌变化。结果
激光照射可以提高自酸蚀树脂水门汀Panavia F和自粘接树脂水门汀RelyX Unicem与牙本质之间的剪切强度（P＜0.05）。激光会降低全酸蚀树脂水门汀RelyX ARC与牙本质间的剪切强度（P＜0.05）。根管显微镜下观察可见：试件断裂大部分发生在树脂水门汀-牙本质界面。扫描电镜观察可见：Nd: YAG激光照射后,全酸蚀亚组和自酸蚀亚组的混合层变薄、树脂突变短且少;自粘接亚组变化不明显,未见树脂突。结论Nd: YAG激光照射后,可提高Panavia F和RelyX Unicem与牙本质的剪切强度,建议临床联合应用。     

四种树脂粘接剂与牙釉质和牙本质粘接性能的比较

目的 评价4种树脂粘接剂与牙釉质和牙本质的粘接强度以及粘接界面微观形态,以期为临床应用提供依据.方法 选取24颗新鲜拔除的无龋坏人磨牙,每颗牙制取牙釉质和牙本质试件各2片,均分为4组,每组牙釉质和牙本质试件各12片.选用4种树脂粘接剂(A组:PanaviaTMF;B组:RelyXTM ARC;C组:RelyXTM Unicem;D组:ClearfilTM SA Cement)进行粘接处理后,在扫描电镜(SEM)下观察粘接界面,并测试粘接强度.结果 B组牙釉质粘接强度[(29.38±6.28)MPa]高于D组[(27.25±7.03)MPa],但两者差异无统计学意义(P＞0.05),两者均显著高于A组[(22.92±7.13)MPa]和C组[(10.92±3.41)MPa,P＜0.05].B组牙本质粘接强度[(27.28±6.79)MPa]最高,随后依次为A组[(14.23±6.39)MPa]、D组[(10.09±3.26)MPa]和C组[(6.43±1.60)MPa],各组间差异均有统计学意义(P＜0.05).B组牙釉质粘接界面可见树脂突,A、B组牙本质粘接界面可见树脂突.结论 四种树脂粘接剂表现出不同的牙釉质、牙本质粘接性能.

Abstract：

Objective To evaluate the dentin and enamel bonding strength and resin-dentin interfaces of four resin cements. Methods Twenty-four sound freshly extracted molars were sectioned with low-speed saw under running water. Two mesial-distal enamel disc and two buccal-lingual dentin discs were sectioned from each molar. Four resin cements( A group: PanaviaTM F; B group: RelyXTM ARC; C group:RelyXTM Unicem; D group: ClearfilTM SA Cement) were applied to the surface of these enamel and dentin discs according to manufacturers' guidance. The bonded specimen were prepared for shear bond strength test and sectioned occluso-gingivally into two slabs for scanning electron microscopy(SEM) observation. Results The bonding strength between resin and enamel in B group[ (29. 38 ±6. 28) MPa] was higher than that in D group[ (27.25 ± 7.03) MPa], and both of them were significantly higher than those in A [ ( 22.92 ±7. 13) MPa] and C group [ ( 10.92 ± 3.41 ) MPa] ( P ＜ 0.05 ). The highest dentin bonding strength was shown in B group [ ( 27.28 ± 6. 79 ) MPa ], followed by A [ ( 14. 23 ± 6. 39 ) MPa ], D [ ( 10.09 ±3.26) MPa] and C group[ (6. 43 ± 1.60) MPa, P ＜ 0.05 ]. Conclusions The four resin cements have different enamel or dentin bonding properties.     

表面处理对双固化黏结剂Panavia F黏接强度的影响

目的评价表面处理对双固化黏结剂Panavia F与不同界面黏接强度的影响。方法测定Panavia F与牙本质使用和不使用牙本质处理剂ED primer时的剪切强度,以及Panavia F与钴铬合金、镍铬合金、纯钛、银金钯合金使用和不使用金属表面处理剂Alloy primer时的剪切强度,数据作统计学检验,分析其黏接机制。结果使用ED primer处理后,Panavia F与牙本质的剪切强度从9.1MPa提高到17.6MPa;使用Alloy primer处理后,Panavia F与纯钛的剪切强度从29.0MPa提高到35.9MPa,而与处理后的银金钯合金的剪切强度从21.6MPa提高到30.2MPa。结论Panavia F通过采用ED primer对牙本质的表面处理显著提高对牙本质的黏结强度;Alloy primer可以显著提高纯钛和贵金属与黏结剂的黏结强度,而对钴铬合金和镍铬合金则不明显。     

Evaluation of a 4-META adhesive cement

This study investigated the shear bond strength of a new 4-META adhesive cement (C & B-Metabond) to dentin and Ni-Cr-Be alloy (Rexillium III). Fifteen human molar teeth had dentin bonding sites prepared by grinding away the enamel on a water-cooled abrasive wheel to a 600 grit. Fifteen metal alloy specimens were cast, ground to a 600 grit, and air abraded with 50 micron alumina. The 4-META cement was applied to the dentin and metal in accordance with the manufacturer's instructions. After 24 hours in water at 37 degrees C, the shear bond strengths were recorded. The mean bond strength to dentin and the metal alloy was 20.1 megapascals.