偶联剂和不同粘接剂对纤维桩粘接强度的影响

目的:利用薄片推出实验比较硅烷偶联剂和三种树脂粘接剂对纤维桩剪切粘接强度的影响.方法:60颗因牙周病等原因拔除的上颌单根前牙,根管治疗后行纤维桩修复的桩道预备.随机分为5组,每组12颗牙.分别采用下列粘接剂粘接Matchpost纤维桩:A组:Paracore粘接剂+偶联剂;B组:Paracore粘接剂;C组:Panavia F粘接剂+偶联剂;D组:Panavia F粘接剂;E组:Multilink N粘接剂+偶联剂.纤维桩粘接后,在牙根中部横向切割1.0mm层厚切片2个,在Zwick Z100材料试验机上行薄片推出试验(Push-Out Bond Test),记录失败载荷,计算剪切粘接强度,体视显微镜观察粘接失败类型.结果采用SPSS 11.5进行方差分析和χ2检验.结果:五组样本的剪切粘接强度(MPa)分别为A组:14.69±2.76;B组:9.46±3.11;C组:13.12±3.10;D组:10.40±3.30;E组:13.86±3.81,方差分析提示五组间差异有统计学意义(P <0.01).采用偶联剂处理时,Paracore粘接剂和Panavia F粘接剂与纤维桩间的剪切粘接强度均高于未用偶联剂处理者(P <0.05).采用偶联剂处理时,三种树脂粘接剂与纤维桩的剪切粘接强度间差异无统计学意义(P >0.05).五组粘接失败类型间差异有统计学意义(P <0.05),未采用硅烷偶联剂处理纤维桩表面者,出现纤维桩-粘接剂界面失败者增多.结论:在树脂粘接前,玻璃纤维桩表面氢氟酸酸蚀后,采用硅烷偶联剂处理可显著提高纤维桩与树脂粘接剂间的剪切粘接强度.     

三种粘接剂粘接不同牙本质的微拉伸粘接强度比较

目的采用微拉伸粘接强度实验测定3种牙本质粘接剂粘接楔状缺损处硬化牙本质的粘接强度。方法选择有典型楔状缺损并因牙周病拔除的上颌前磨牙30颗作为实验组，正常上颌前磨牙30颗作为对照组，使用粘接剂A（全酸蚀粘接剂Scotchbond Multi—Purpose）、B（一步法自酸蚀粘接剂Adper Prompt L-Pop）和C（两步法自酸蚀粘接剂Contax）处理硬化牙本质和正常牙本质表面，相应树脂修复。测试两组试件的微拉伸粘接强度。结果粘接剂A、B、C粘接硬化牙本质的微拉伸粘接强度分别为46．805MPa、39．045MPa、29．852MPa。粘接剂A和C与硬化牙本质的微拉伸粘接强度低于正常牙本质，而粘接剂B与之相反，差异有统计学意义（P〈0．05）。结论牙颈部楔状缺损处硬化牙本质由于结构上的特殊性可造成粘接困难。酸性强有利于粘接剂与硬化牙本质的粘接。     

一步法自酸蚀粘接剂微拉伸粘接强度的研究

目的评价一步法白酸蚀粘接剂的牙本质微拉伸粘接强度，观察并分析样本断裂类型。方法选择新拔除的人无龋下颌第三磨牙12颗，分别用3种一步法、1种两步法的白酸蚀粘接剂进行牙本质粘接。用微拉伸测力仪测试粘接强度，并用体视显微镜和扫描电镜观察样本断裂类型。结果3种一步法白酸蚀粘接剂的微拉伸强度分别为：材料A（Adper Prompt）（23．36±2．55）MPa；材料B（Clearfil S^3 Bond）（30．46±3．82）MPa；材料C（Xenon Ⅲ）（34．59±3．46）MPa；1种两步法自酸蚀粘接剂材料D（Clearfil SE Bond）的微拉伸粘接强度为（45．06±5．29）MPa。材料D微拉伸粘接强度最高，与其他3组相比，差异具有统计学意义（P〈0．01）。样本断裂均发生于粘接界面，未观察到复合树脂或牙本质内聚破坏。结论一步法白酸蚀粘接剂的牙本质粘接强度低于两步法白酸蚀粘接剂，但多数仍可满足临床对树脂粘接强度的要求。     

五种牙本质粘接剂对乳牙牙本质粘接性能的比较

目的 检测5种牙本质粘接剂对乳牙牙本质的粘接性能,为牙本质粘接剂的临床使用提供依据.方法 按随机数表法将75颗因滞留拔除的乳磨牙分为5组,每组15颗.各标本磨除表面牙釉质,暴露的牙本质面分别根据不同粘接系统的说明进行酸蚀粘接,树脂充填.使用A(FL-Bond Ⅱ)、B(Clearfil Protect Bond)、C(Clearfil SE Bond)、D(AdperTM Easy One)、E(Single Bond 2)粘接系统进行粘接(分别为A、B、C、D、E组),用微拉伸测试仪检测微拉伸强度.扫描电镜观察样本的断裂类型.结果 各组的微拉伸强度分别为A组:(28.3±2.2)MPa,B组:(32.4±2.5)MPa,C组:(38.3±2.8) MPa,D组:(32.9±3.4)MPa,E组:(23.2±1.9) MPa,C组与A、E组差异有统计学意义(P＜0.01),C组与B组、D组差异无统计学意义(P＞0.05),A组与E组差异无统计学意义(P＞0.05).扫描电镜观察显示各组的断裂类型均以混合断裂为主,各组间无明显差异.结论 粘接剂B的粘接强度与粘接剂C和D相同,优于粘接剂E,可能更适用于乳牙的粘接.     

粘结剂类型对核树脂与牙本质的微拉伸粘结强度的影响

目的测试不同的粘结剂类型对核树脂与牙本质的粘结强度的影响,为临床选择合适的粘结剂和核树脂提供参考。方法选择20颗因阻生拔除的健康第三磨牙,磨除牙合面釉质,形成牙本质平面。随机分成ABCD四组,每组5颗牙齿。A组、B组所有牙本质粘结面涂布自酸蚀Contax粘结剂。C组和D组牙本质粘结面酸蚀剂处理后涂布SingleBond粘结剂,A组和C组用Luxa-Core核树脂,B组和D组用3MFiltekTMZ350纳米树脂进行分层固化粘结,切成约0.9mm×0.9mm的柱状试件,每组共30个试件。用微拉伸测试仪检测其粘接强度,用扫描电镜观察样本粘接界面的超微形态。结果 A组（36.03±9.25）MPa和B组（23.38±9.78）MPa与C组（14.27±8.63）MPa相比,差异有统计学意义（P〈0.05）,D组（38.80±10.56）MPa与B组、C组相比,差异有统计学意义（P〈0.05）,A组和D组相比,差异无统计学意义（P〉0.05）。两种核树脂的粘结界面均可见牙本质小管有树脂突形成,SingleBond酸蚀组树脂突比Contax自酸蚀组分布密度较密,长度较长。结论不同的粘结剂类型对核材料与牙本质的粘结强度有影响,要选择核树脂配套的粘结剂。     

温度循环老化对复合树脂间粘接强度的影响

目的 探讨复合树脂和粘接界面老化后树脂间粘接强度的变化,以期为临床工作提供实验依据.方法 纳入甲基丙烯酸酯类复合树脂(Clearfil AP-X,树脂A)及其配套粘接剂(Clearfil SEBond,粘接剂a)和环氧树脂(Filtek P90,树脂B)及其配套粘接剂(Filtek P90 System Adhesive,粘接剂b).将树脂A、B分别制作基底树脂块各24块,各分为3组,每组8块:①对照组,基底树脂块表面涂布粘接剂,充填固化新树脂后切成条状试样;②粘接界面老化组,基底树脂块粘接新树脂后切成条状试样,行温度循环老化;③基底树脂老化组,将基底树脂块行温度循环老化后打磨表面,再粘接新树脂,最后切成条状试样.每组中由基底树脂(A、B)-粘接剂(a、b)-新树脂(A、B)构成8种粘接组合,每一组合设2个平行样.体视显微镜下筛选条状试样,每个粘接组合获得15条微拉伸试样,用微拉伸测试仪检测微拉伸强度,对不同粘接组合中粘接界面老化组与对照组、基底树脂老化组与对照组的微拉伸强度行独立样本t检验.结果 粘接界面老化组中,由粘接剂a粘接新树脂A或B的粘接组合[A-a-A:(45.0±3.2)MPa,B-a-A:(41.7±3.3) MPa,A-a-B:(28.6±3.9) MPa,B-a-B:(47.7±6.6) MPa],及由粘接剂b粘接新树脂A的粘接组合[A-b-A:(44.2±4.7) MPa,B-b-A:(38.0±3.2) MPa],微拉伸强度均显著低于各自对照组[A-a-A:(70.7±5.5) MPa,B-a-A:(60.3±5.1) MPa,A-a-B:(44.2±1.6) MPa,B-a-B:(54.1±3.2) MPa,A-b-A:(65.6±7.2) MPa,B-b-A:(59.1±4.1) MPa](P＜0.05);而由粘接剂b粘接新树脂B的粘接组合A-b-B及B-b-B的微拉伸强度与各自对照组相比差异均无统计学意义(P＞0.05).基底树脂老化组中,各粘接组合的微拉伸强度均显著低于各自对照组(P＜0.05).结论 复合树脂和粘接界面的老化均可对复合树脂间的粘接强度产生影响.     

两种脱敏剂对牙本质粘接剂粘接强度的影响

目的 探讨两种脱敏剂对牙本质粘接剂粘接强度和微观形态的影响,以期对临床治疗有所指导.方法 将30颗完整且无龋的人第三磨牙去除(牙合)面釉质,采用随机数字表法随机分为3组:C组(对照组)、U组(UltraEZTM处理)和M组(MI Paste处理);每组10颗牙齿.C组不做处理,U组和M组分别使用相应脱敏剂对暴露的牙本质表面进行处理.3组样本牙再各随机分为两个小组,每小组5颗牙,分别用粘接剂A(Single Bond 2)和B(Xeno Ⅲ)粘接,用复合树脂修复达4～5 mm.用慢速锯将牙齿切成粘接面积为0.9 mm×0.9 mm的长方体试件,用微拉伸测试仪测试微拉伸强度,作为粘接强度,对其进行单因素方差分析.每组随机挑选3个试件对粘接界面进行扫描电镜观察.结果 对于粘接剂A,U组粘接强度[(14.58±2.31)MPa]与C组[(15.82±2.18)MPa]的差异无统计学意义(P>0.05),而M组粘接强度[(9.90±0.79)MPa]降低.对于粘接剂B,U组粘接强度[(10.55±1.06)MPa]与C组[(10.73±1.07)MPa]的差异无统计学意义(P>0.05),而M组粘接强度[(8.74±0.87)MPa]降低.扫描电镜见各组混合层均较致密,M组两种粘接剂的树脂突较短且稀少.结论 两种脱敏剂对粘接剂粘接强度的影响不同,U组脱敏剂对全酸蚀和自酸蚀粘接剂的粘接强度无明显影响,而M组脱敏剂可降低两种粘接剂的粘接强度.     

填料含量对实验双固化树脂水门汀与纤维桩黏结强度的影响

目的:比较二氧化硅填料含量对EAM树脂材料黏结性能的影响,为研制纤维桩树脂核修复材料奠定基础.方法:根据二氧化硅填料在EAM树脂中添加含量的不同分为4组(A组:40%、B组:50%、C组:60%、D组:70%),E组(对照组)LuxaCore-Dual树脂,将各组树脂水门汀在圆筒形模具内分别与纤维桩黏结后,制备成微拉伸试件.用微拉伸试验机进行拉伸,直至试件破坏,并作统计学处理.结果:4个不同二氧化硅无机填料组的微拉伸强度分别为:A组(10.15±2.72)MPa,B组(11.48±2.81)MPa,C组(12.03±2.78)MPa,D组(10.07±2.06)MPa,E组(10.88±2.85)MPa,B、C两组的黏结强度显著高于A、D、E组(P<0.05).结论:60%左右无机填料含量的复合树脂微拉伸黏结强度较为理想.     

空气喷磨处理氟斑牙牙釉质对树脂粘接强度的影响

目的：检测空气喷磨处理对氟斑牙牙釉质与复合树脂间粘接强度影响。方法：根据Dean氏分类标准,选择15颗完整无龋坏的氟斑牙患者因正畸需要拔除的第一前磨牙为研究对象,随机分为A（单纯酸蚀）、B（单纯喷磨）、C（喷磨加酸蚀）三组进行釉质表面处理后粘接树脂,采用微拉伸粘接强度实验测定三组试件的微拉伸粘接强度。结果：A、B、C三组牙釉质粘接树脂后的微拉伸粘接强度分别为（23.48±5.71）MPa、（16.55±3.52）MPa、（29.24±4.61）MPa,各组微拉伸粘接强度平均值间差异有统计学意义（P〈0.01）。结论：采用空气喷磨加酸蚀预处理氟斑牙牙釉质可以提高氟斑牙牙面与复合树脂的粘接力。     

自酸蚀与全酸蚀粘接剂对牙釉质和牙本质的剪切粘接强度比较

目的 比较自酸蚀与伞酸蚀粘接剂对牙釉质和牙本质剪切粘接强度,以期为临床提供参考.方法 选择因牙周病拔除的上颌中切牙20颗,使用两种自酸蚀粘接剂[A(ClearfilTM Protect Bond)、B(AdporTM PromptTM)]和两种全酸蚀粘接剂[C(SwissTEC SL Bond)、D(Single Bond)]按照厂家推荐步骤对牙釉质和牙本质进行粘接,并测试牙釉质和牙本质粘接样本的剪切粘接强度.结果 4种粘接剂对牙釉质和牙本质粘接强度分别为:粘接剂A(25.33±2.84)、(26.07±5.56)MPa;粘接剂B(17.08±5.13)、(17.93±4.70)MPa;粘接剂C(33.14±6.05)、(41.92±6.25)MPa;粘接剂D(22.51±6.25)、(21.45±7.34)MPa.粘接剂C对牙釉质和牙本质剪切粘接强度显著高于其他3种粘接剂(P<0.05);粘接剂B的剪切粘接强度显著低于其他3种粘接剂(P<0.05).结论 本研究所选用的自酸蚀两步法粘接剂的剪切粘接强度与部分伞酸蚀粘接剂相当,高于自酸蚀一步法粘接剂.     

Effects of surface treatments on shear bond strengths between a resin cement and an alumina core

STATEMENT OF PROBLEM: Although bonding to all-ceramic restorations is desirable, there is little information on the use of resin cements containing a phosphate monomer, and the importance of different surface treatments on their adhesion to high-strength core materials. PURPOSE: This study attempted to determine the shear bond strength values between Panavia 21 resin cement (Kuraray) and an alumina core material (In-Ceram) after 3 surface treatments and the application of a silane coupling agent. MATERIAL AND METHODS: Forty-five In-Ceram cylindrical rods were fabricated and assigned to 3 groups. Group I specimens were treated with a 9.5% hydrofluoric (HF) acid, group II with a 5% HF acid, and group III were sandblasted. All specimens were coated with a silane coupling agent (Cavex Clearfil Photobond and Activator) before cementation with Panavia 21 to sandblasted nickel-chromium rods. As a control, group IV consisted of 8 porcelain (Vitadur Alpha) rods treated with a 5% HF acid and silane. All specimens were subjected to a load of 1.2 kg during cementation, then stored under water for 36 hours. A jig mounted on a Hounsfield Universal Testing machine was used at a crosshead speed of 0.5 mm/min to test the shear bond strengths. RESULTS: The results were 14.65 +/- 4.64 MPa for group I, 18.03 +/- 6.13 MPa for group II, and 22.35 +/- 5.98 MPa for group III In-Ceram specimens; and 18.05 +/- 8.46 MPa for control (group IV). CONCLUSION: The use of Panavia 21 resin cement and a silane coupling agent can achieve a successful bond between either sandblasted or 5% HF acid-etched In-Ceram core material.     

不同浓度H2O2的桩表面处理对玻璃纤维桩与树脂水门汀黏结强度的影响

目的：研究不同浓度的H2O2表面处理对纤维桩与树脂水门汀之间黏结强度的影响。方法：选择2种不同种类的玻璃纤维桩各18支,随机分为6组,A组(对照组)、B组(单纯硅烷化处理)、C组(3%H2O2+硅烷化处理)、D组(10%H2O2+硅烷化处理)、E组(20%H2O2+硅烷化处理)和F组(30%H2O2+硅烷化处理)。将各组纤维桩与树脂水门汀进行黏结,形成圆柱状树脂块,将每个树脂块切割成7个1.0 mm厚的薄片进行推出实验,记录数据并采用SPSS13.0软件包对数据进行统计学分析。测试后的试件置于光学显微镜下,观察其破坏模式。结果：Tenax玻璃纤维桩黏结强度值A1-F1组分别为 (22.35±3.43) MPa 、(22.75±1.92) MPa、(27.21±3.60) MPa、(32.32±2.19) MPa、(36.15±2.32) MPa和(40.51±2.37) MPa,Macthpost玻璃纤维桩黏结强度值A2-F2组分别为(17.29±3.23) MPa、(17.01±3.18) MPa、(20.48±2.11) MPa 、(23.60±2.60) MPa 、(27.65±3.77) MPa和(30.52±2.99) MPa。Tenax及Matchpost组中,除了A组和B组无显著差异(P>0.05)外,其余每2组间相比,差异均有显著性(P<0.05)。结论：使用H2O2溶液处理Tenax及Matchpost玻璃纤维桩表面再涂以硅烷偶联剂,可明显提高2种玻璃纤维桩与树脂水门汀之间的黏结强度。30%H2O2溶液处理玻璃纤维桩表面的黏结强度最高,可使其更利于黏结。     

不同表面处理方法对纤维桩与树脂黏结强度的影响

目的： 比较5种不同表面处理方法对纤维桩黏结强度的影响。方法：50根纤维桩按照表面处理方法的不同,随机分为5组,A组为硅烷偶联剂组（Clearfil Porcelain Bond Activator,Kuraray）,B组为硅烷偶联剂+黏结剂组（A+ Clearfil SE Bond,Kuraray）,C组为过氧化氢组（30%H₂O₂溶液）,D组为过氧化氢+硅烷偶联剂组（C+A）,E组为对照组。分别与树脂黏结剂黏结后,每组再平均分成2个小组,1组37℃生理盐水保存24 h后进行微拉伸强度测试,1组37℃生理盐水保存24 h后进行10000次冷热循环再进行微拉伸强度测试。采用SPSS17.0软件包对数据进行统计学分析。结果：冷热循环前A组~E组的微拉伸黏结强度分别为（6.7±0.7）、（14.4±1.1）、（10.7±0.9）、（16.0±1.0）和（6.7±1.0） MPa,冷热循环后,A组~E组的微拉伸黏结强度分别为（6.0±0.7 ）、（13.1±0.7）、（9.0±0.7）、（15.0±0.9 ） 和（5.6±0.7） MPa。除硅烷偶联剂组与对照组之间外,其余各组之间差异均有显著性（P<0.05）,其中,过氧化氢+硅烷偶联剂组黏结强度最大。各组之间在冷热循环前、后的微拉伸黏结强度差异均有显著性（P<0.05）。结论：温度疲劳循环可以降低5种表面处理的纤维桩与树脂间的黏结强度,30%H₂O₂溶液处理纤维桩后再使用硅烷偶联剂,可显著增加纤维桩与树脂之间的黏结强度。     

Effect of different ceramic surface treatments on resin microtensile bond strength.

PURPOSE: The objective of this study was to evaluate the effect of different surface treatments on the microtensile bond strength (micro-tbs) of composite bonded to hot-pressed ceramic. The null hypothesis tested was that neither of the surface treatments (silanization or fluoric acid etching) would produce greater bond strength of composite resin to the ceramic. MATERIALS AND METHODS: Four 7 x 7 x 5 mm hot-pressed ceramic blocks of IPS Empress 2 were fabricated and polished to 600 grit followed by sandblasting with 50 microm alumina. The ceramic blocks were then divided into four groups and submitted to the following surface treatments: Group 1: 9.5% hydrofluoric (HF) acid for 20 seconds and silane (S) for 3 minutes; Group 2: silane for 3 minutes; Group 3: 9.5% HF acid for 20 seconds; Group 4: no treatment. Scotchbond adhesive was applied to the treated ceramic surfaces and covered with Filtek Z250 composite resin. The composite-ceramic blocks were cut with an Isomet low speed diamond saw machine producing sticks (n = 25), which were loaded to failure under tension in an Instron Universal testing machine. The mean micro-tbs was analyzed with one-way ANOVA and Bonferroni "t" test. RESULTS: All specimens of Group 4 experienced adhesive failure during the cutting of the block and were eliminated. The mean micro-tbs and standard deviations (SD) in megaPascals were: Group 1 = 56.8 (+/-10.4), Group 2 = 44.8 (+/-11.6), Group 3 = 35.1 (+/-7.7). Statistical analysis showed that the bond strength was significantly affected by surface treatment (p < 0.0001). Group 1 (HF + S) had the highest micro-tbs, and Group 2 (S) had higher micro-tbs than Group 3 (HF). The mode of fracture of the specimens was examined using scanning electron microscopy (SEM), and all fractures occurred within the adhesion zone. Conclusion: The results show that surface treatment is important for resin adhesion to ceramic and suggestthat silane treatment was the main factor responsible for resin bonding to ceramic.     

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.     

Effects of ceramic surface treatments on the bond strength of an adhesive luting agent to CAD-CAM ceramic

OBJECTIVES: The objective of this study was to evaluate the effect of different surface treatments on the micro-tensile bond strength (microTBS) of an adhesive luting agent to CAD-CAM ceramic. The hypothesis tested was that neither of the surface treatments would produce higher bond strength of the adhesive luting agent to CAD-CAM ceramic. METHODS: Ceramic specimens of two different sizes (6 mm x 8 mm x 3 mm; 13 mm x 8 mm x 4 mm) were fabricated from ProCAD ceramic blocs (Ivoclar-Vivadent) with a low-speed diamond saw. The ceramic blocks were divided into seven groups and submitted to the following surface treatments: group 1: no treatment; group 2: etching with 37% H(3)PO(4); group 3: etching with 37% H(3)PO(4)+silane; group 4: etching with 37% H(3)PO(4)+silane+adhesive resin; group 5: etching with 4.9% HF acid; group 6: etching with 4.9% HF acid+silane; group 7: etching with HF acid+silane+adhesive resin. After surface treatment, two differently sized porcelain disks were bonded together with a composite luting agent (Variolink II, Ivoclar-Vivadent). The specimens were stored for 24h in distilled water at 37 degrees C prior to microTBS testing. One-way analysis of variance was used to test the influence of surface treatment and Scheffe multiple comparisons test determined pair-wise statistical differences (p<0.05) in microTBS between the experimental groups. RESULTS: The mean microTBSs (standard deviation) are: group 1: 12.8 (+/-4.6)MPa; group 2: 19.1 (+/-5.0)MPa; group 3: 27.4 (+/-11.1)MPa; group 4: 34.0 (+/-8.9)MPa; group 5: 37.6 (+/-8.4) MPa; group 6: 34.6 (+/-12.8)MPa; group 7: 34.5 (+/-5.1)MPa. Statistical significant differences were found between group 1 and groups 3-7, and between group 2 and groups 4-7. All specimens of groups 1-4 exhibited adhesive failures, while a combination of adhesive and mixed (adhesive and cohesive) failures was observed in the specimens of groups 5-7. CONCLUSIONS: The results show that surface treatment is important to bond to ceramic and suggests that etching is needed preferably with hydrofluoric acid than with phosphoric acid.     

纳米硅涂层对玻璃渗透氧化铝陶瓷粘结强度的影响

目的：探讨利用溶胶凝胶法进行纳米硅涂层表面改性对玻璃渗透氧化铝陶瓷粘结强度的影响。方法：3组In-Ceram氧化铝瓷块分别施以“喷砂（P组）”、“喷砂＋硅烷偶联（PO组）”、“喷砂＋纳米硅涂层＋硅烷偶联（PTO）组）”的表面处理。制作陶瓷／复合树脂粘结体,室温下置蒸馏水中浸泡24h,微拉伸法测试各组试件粘结强度。结果：P组与PO组粘结强度较弱且无明显差异（P=0．797）,PTO组的粘结强度明显高于其他组（P〈0．05）。结论：通过溶胶凝胶法在喷砂表面制备纳米硅涂层后应用硅烷偶联剂可以显著提高In-Ceram氧化铝陶瓷的粘结强度。     

Influence of acid-etching and ceramic primers on the repair of a glass ceramic

The objective of this study was to evaluate the influence of different primers on the microtensile bond strength (μTBS) between a feldspathic ceramic and two composites. Forty blocks (6.0 x 6.0 x 5.0 mm3) were prepared from Vita Mark II . After polishing, they were randomly divided into 10 groups according to the surface treatment: Group 1, hydrofluoric acid 10% (HF) + silane; Group 2, CoJet + silane; Group 3, HF + Metal/Zirconia Primer; Group 4, HF + Clearfil Primer; Group 5, HF + Alloy Primer; Group 6, HF + V-Primer; Group 7, Metal/Zirconia Primer; Group 8, Clearfil Primer; Group 9, Alloy Primer; Group 10, V-Primer. After each surface treatment, an adhesive was applied and one of two composite resins was incrementally built up. The sticks obtained from each block (bonded area: 1.0 mm2 ± 0.2 mm) were stored in distilled water at 37 degrees C for 30 days and submitted to thermocycling (7,000 cycles; 5 degrees C/55 degrees C ± 1 degree C). The μTBS test was carried out using a universal testing machine (1.0 mm/min). Data were analyzed using ANOVA and a Tukey test (a = 0.05). The surface treatments significantly affected the results (P < 0.05); no difference was observed between the composites (P > 0.05). The bond strength means (MPa) were as follows: Group 1a = 29.6; Group 1b = 33.7; Group 2a = 28.9; Group 2b = 27.1; Group 3a = 13.8; Group 3b = 14.9; Group 4a = 18.6; Group 4b = 19.4; Group 5a = 15.3; Group 5b = 16.5; Group 6a = 11; Group 6b = 18; Groups 7a to 10b = 0. While the use of primers alone was not sufficient for adequate bond strengths to feldspathic ceramic, HF etching followed by any silane delivered higher bond strength.     

两种粘结剂对Cerec3D全瓷冠抗折强度的实验研究

目的:探讨Cerec 3D全瓷冠粘结后冠抗折强度。方法:选择无龋坏上颌前磨牙40颗分为1、2、3、4组,完成Cerec全瓷冠,分别用Variolink N+硅烷偶联剂,Variolink N,Bisco Choice2TM+硅烷偶联剂,Bisco Choice2TM粘结。4°C 0.9%氯化钠液中保存24 h后,用万能力学试验机测试其冠最大抗折强度,记录数据;在体式显微镜下观察粘结破坏形式。采用SPSS 17.0软件包比较冠抗折强度和粘结破坏形式。结果:Variolink N+硅烷偶联剂组冠抗折强度最高。结论:双重固化树脂粘结系统是牙科长石质陶瓷粘结的理想选择,可获得较高抗折强度。硅烷偶联剂可增强全瓷冠抗折强度。     

Light transmission and bond strength of glass fiber posts submitted to different surface treatments

Statement of problemLight transmitted deep into the root canal is an important parameter to increase bonding of the cement to the post and dentin. Glass fiber posts seem to be an option to increase transmitted light, but literature on the light transmittance profile and power transmission to deep canal regions is lacking.PurposeThe purpose of this in vitro study was to evaluate light delivered by 2 types of fiberglass posts submitted to different surface treatments and to evaluate the bond strength.Material and methodsWhiteposts and Superposts were allocated to 4 groups: no surface treatment, surface treatment with 24% hydrogen peroxide, surface treatment with silane, and surface treatment with 24% hydrogen peroxide plus silane. The total light transmitted by the posts was measured by using an integrating sphere to collect the diffuse light. The light profile that was laterally delivered to the post was measured with a power detector equipped with an optical fiber probe. The bond strength was measured with the push-out test. Scanning electron microscopy was used to evaluate the surface treatments. The light transmission data were analyzed by using a generalized linear model and the Bonferroni test and the bond strength values were evaluated by using ANOVA and the Tukey test (α=.05).ResultsThe cervical third presented the highest transmission (74.1% for Whiteposts and 74.6% for Superposts), followed by the middle (20.9% for Whiteposts and 20.4% for Superposts) and apical (5.0% for both Whiteposts and Superposts) thirds. Superposts led to higher bond strength than Whiteposts (9.73 ±5.89 and 8.48 ±4.99 MPa, respectively). Surface treatment with silane and hydrogen peroxide plus silane afforded similar bond strength (11.4 ±6.4 and 10.7 ±5.6 MPa, respectively), which was higher as compared with the bond strength obtained after surface treatment with hydrogen peroxide. For both post types, the bond strength decreased from the cervical (12.2 ±6.0 MPa) to the middle (9.7 ±5.0 MPa) and apical (6.5 ±3.6 MPa) thirds.ConclusionsLight transmission and bond strength decreased from the cervical to the apical third. Surface treatment impacted bond strength; light transmission through Whiteposts was slightly higher than light transmission through Superposts.