酸蚀牙面后黏结树脂嵌体修复牙体的抗力性能

背景：树脂嵌体修复牙体缺损在一定程度上可减少修复后牙齿的折裂,但嵌体经不同方法黏结处理后对牙体抗力的影响未见报道。 目的：了解复合树脂经不同方法处理后修复牙体的抗力特性。 方法：将40颗无龋人前磨牙制作近中-牙合面-远中洞型洞,随机分成4组：其中一组备洞后未进行修复作为对照组,其他3组分别以可乐丽菲露光固化复合树脂直接充填,可乐丽菲露光固化复合树脂嵌体直接黏结和酸蚀黏结修复。 结果与结论：①力学模型静态力学加载实验结果：树脂直接充填组、树脂嵌体直接黏结和酸蚀黏结组断裂载荷均高于对照组(P < 0.05),前3组断裂载荷比较组间差异无显著性意义(P > 0.05),树脂嵌体酸蚀黏结组断裂载荷最大。②扫描电镜观察结果：树脂直接充填组断裂位于牙本质层和树脂之间,几乎无树脂残留,有较多孔隙;树脂嵌体直接黏结组大量牙本质基体与树脂间断裂,有较少树脂残留;树脂嵌体酸蚀黏结组牙与树脂之间无气泡、无缝隙、相互嵌合、紧密接触;对照组,树脂直接充填、直接黏结、酸蚀黏结组分别出现10,5,3,1个样本树脂内聚破坏断裂。表明经酸蚀处理复合树脂嵌体可提高牙体力学性能。     

不同树脂黏结剂对纤维桩冠向微渗漏及黏结强度的影响

背景：目前国内外对全酸蚀、自酸蚀及自黏结树脂黏结剂对纤维桩的冠向微渗漏及黏结强度影响的研究仍存在差异。 目的：评价全酸蚀、自酸蚀及自黏结3种树脂黏结剂对纤维桩黏固后冠向微渗漏及黏结强度影响。 方法：将32颗人离体上前牙随机分成5组,其中3组为实验组,2组为对照组。实验组离体牙经根管预备后,选用全酸蚀、自酸蚀及自黏结3种树脂黏结剂分别黏结直径为1.4 mm的玻璃纤维桩。体视显微镜下观察试件各剖面的微渗漏情况,再将实验组试件沿垂直牙长轴方向切成厚度为2 mm的薄片,万能材料测试机进行微推出实验,并观察试件断裂方式。阳性对照组不进行根管预备,根部涂布指甲油,冠部直接暴露于染色剂中;阴性对照组不进行根管预备,树脂覆盖根管口,将牙体整体涂布指甲油后黏蜡包埋至截面下1 mm。 结果与结论：各种树脂黏结剂均存在微渗漏现象,其中全酸蚀树脂黏结剂的微渗漏程度最轻,自酸蚀树脂黏结剂的微渗漏程度最重。3种树脂黏结剂间的微渗漏程度差异有显著性意义(P < 0.05)。黏结剂间的黏结强度由高到低分别为全酸蚀树脂黏结剂、自酸蚀树脂黏结剂、自黏结树脂黏结剂,3种黏结剂的黏结强度差异有显著性意义(P < 0.05)。试件的主要断裂方式为黏结剂/纤维桩间断裂及混合破坏。说明全酸蚀树脂黏结剂与牙本质结合紧密,与自酸蚀树脂黏结剂、自黏结树脂黏结剂比较在微渗漏程度及黏结性能方面显示出优越性。     

枸橼酸酸蚀牙本质的最佳浓度和时间

背景：虽然目前枸橼酸溶液已被逐渐运用于制作牙本质敏感模型方面的研究,但仍未得出一个有效的统一浓度及酸蚀时间。 目的：观察不同浓度枸橼酸酸蚀牙本质盘不同时间的效果,以获得研究牙本质敏感症的可靠体外实验模型。 方法：选取30颗前磨牙并制作成牙本质盘,经碳化硅水磨砂纸抛光、枸橼酸酸蚀处理,扫描电镜观察牙本质盘表面酸蚀后的形态学特征,测量牙本质小管的直径,比较分析不同浓度枸橼酸溶液(5%,10%,15%)分别酸蚀不同时间(30,60,120,180 s)对牙本质样本表面玷污层的去除效果、开放牙本质小管的能力。 结果与结论：枸橼酸溶液具有较强的酸蚀作用,其去除玷污层的能力随着酸蚀时间延长及溶液浓度的增加而加强。5%枸橼酸溶液酸蚀各时间组、10%和15%枸橼酸溶液酸蚀30 s或60 s时去除玷污层能力有限,仍有牙本质小管受到不同程度的玷污层覆盖;10%、15%浓度组各酸蚀120,180 s均可使表面玷污层去除,暴露牙本质小管。15%枸橼酸酸蚀120,180 s组的牙本质小管直径较10%浓度组大(P < 0.05),而10%枸橼酸酸蚀120,180 s组的牙本质小管直径差异无显著性意义   (P > 0.05)。提示10%枸橼酸溶液酸蚀牙本质样本120 s是去除玷污层,暴露牙本质小管的最佳方法。关键词：牙本质敏感模型;枸橼酸;牙本质;扫描电镜;牙本质小管直径 doi:10.3969/j.issn.1673-8225.2012.16.026     

黏结剂不同使用方式对全酸蚀树脂水门汀与牙本质间黏结性能的影响

背景：在临床治疗过程中,修复体连同黏结材料一同脱落及产生微小渗孔等情况常有发生,因此,探究黏结剂不同使用方式对全酸蚀树脂水门汀与牙本质间黏结性能的影响具有重要的临床意义。 目的：对比黏结剂不同使用方式对全酸蚀树脂水门汀与牙本质间黏结性能的影响。 方法：获取无龋人新鲜拔除的第二磨牙90颗,随机均分为3组,均于常温水冲洗下打磨消除牙冠部位牙釉质,露出牙本质以制备标准黏结面,分别进行不使用黏结剂处理(对照组)、使用经过光照的全酸蚀树脂水门汀处理(实验2组)、使用未经过光照的全酸蚀树脂水门汀处理(实验1组),检测处理后即刻、处理后再经老化处理的微拉伸黏结强度。 结果与结论：处理后即刻,对照组、实验1组、实验2组的微拉伸黏结强度分别为(8.089±3.431),(11.671±2.561),(8.821±2.513) MPa,组间两两比较差异均有显著性意义(P < 0.05);处理后再经老化处理,对照组、实验1组、实验2组的微拉伸黏结强度分别为(1.069±0.421),(7.621±2.061),(4.821±1.513) MPa,组间两两比较差异均有显著性意义(P < 0.05)。表明全酸蚀树脂水门汀与牙本质的结合在黏结剂不同方法的使用中,无论长期还是短期均是使用不光照处理的黏结剂效果最佳。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

天然药物表没食子儿茶素浸食子酸酯与牙本质龋的再矿化

背景：研究发现表没食子儿茶素浸食子酸酯具有抑制免疫炎症反应、抗菌、抗氧化、抗突变和抗癌等多种功效。 目的：通过体外实验探讨表没食子儿茶素浸食子酸酯对牙本质龋再矿化方面的影响。 方法：将30颗正畸拔除的人离体牙按照随机数字表均分为实验组、对照组及空白对照组,在乳酸脱矿系统制成牙本质龋后,分别置于2 g/L表没食子儿茶素浸食子酸酯溶液、饱和Ca(OH)₂溶液、人工唾液中12 d进行再矿化实验,测定3种溶液中牙本质块表面显微硬度,扫描电镜观察牙本质块表面再矿化结果。 结果与结论：按照再矿化后牙本质表面显微硬度从高到低的顺序依次排列为：对照组、实验组、空白对照组,组间两两比较差异均有显著性意义(P < 0.05),结果表明表没食子儿茶素浸食子酸酯与Ca(OH)₂在牙本质再矿化方面的作用好于人工唾液,两者均能促进牙本质龋的再矿化,且表没食子儿茶素浸食子酸酯促进牙本质龋再矿化效果低于Ca(OH)₂。扫描电镜显示,对照组牙本质表面附着有大量沉积物,未见牙本质小管开口;实验组也可见沉积物附着牙本质表面,但较平整;空白对照组牙本质表面沉积物较少,可见有未覆盖沉积物的牙本质小管口。扫描电镜结果定性证明了表没食子儿茶素浸食子酸酯能促进脱矿牙本质的再矿化。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

硅酸三钙封闭牙本质小管的作用

背景：多项体外实验证实硅酸三钙不仅可以通过自固化过程与牙本质紧密结合,而且在生理环境下能诱导牙本质再矿化,有效阻塞牙本质小管。 目的：进一步验证硅酸三钙对牙本质小管的封闭作用。 方法：选择正畸患者拔除的第一前磨牙制作离体牙本质盘36块,分别经 0.29 mol/L EDTA 内浸置 2 min,6%柠檬酸蚀 1 min 后冲洗,蒸馏水超声清洗 20 min 3种方法预处理,模拟具有牙本质小管不同开放程度的牙本质敏感症。以上每组随机分为3个亚组,即硅酸三钙组、氟化钠对照组、空白对照组,前2组每天早晚分别用对应材料涂刷表面,2 min/次,空白对照组不处理,其余时间全部置于人工唾液 37 ℃恒温箱中保存。14 d后通过扫描电镜观察各组处理前后牙本质形态,并计算开放牙本质小管直径和面积。 结果与结论：经不同预处理后牙本质小管都呈开放状态,但柠檬酸和EDTA预处理溶液较蒸馏水有更强的脱矿作用,牙本质小管更加清晰。各组经氟化钠或硅酸三钙涂擦后,牙本质小管口有不同程度沉积物,且开放牙本质小管面积及平均直径较空白对照组小(P < 0.05);经硅酸三钙涂擦的牙本质小管几乎完全均质封闭,偶见有单个孤立开放的牙本质小管口,开放牙本质小管面积及平均直径都明显低于氟化钠对照组(P < 0.05)。证实硅酸三钙可有效封闭牙本质小管,且效果优于氟化钠;在治疗牙本质过敏时,如果先用EDTA或酸蚀剂处理,脱敏效果会更完善。     

纳米羟基磷灰石封闭牙本质小管的效果

背景：纳米羟基磷灰石是优良的生物活性材料,对脱矿牙釉质和牙本质具有一定的保护作用,但其溶液对脱矿牙本质再矿化的作用及其机制尚不明确。目的：探讨纳米羟基磷灰石用于防治牙本质敏感症和牙本质龋的可行性。方法：收集废弃的人双尖牙标本,制备出72份牙本质薄片,分6组处理：A组脱矿后浸入10%纳米羟基磷灰石溶液中,B组脱矿后浸入6%生物活性玻璃溶液中,C组脱矿后浸入10%纳米羟基磷灰石与6%生物活性玻璃复合溶液中,D组脱矿后浸入0.05%NaF溶液中,E组脱矿后浸入人工唾液中,F组脱矿后浸入去离子水中,每组12个样本。处理14 d后,扫描电镜下观察样本工作面,利用能谱分析仪检测样本表面成分,激光共聚焦显微镜下检测牙本质罗丹明B染色情况。结果与结论：(1)扫描电镜观察：A组牙本质小管口被完全封闭,牙本质表面被一层紧密连接的颗粒物均匀覆盖;C组牙本质小管部分封闭;B、D、E组牙本质表面及牙本质小管内见少量散在颗粒物,牙本质小管口呈开放状;F组牙本质表面及牙本质小管内未见颗粒物沉积,牙本质小管口呈开放状态;(2)X射线能谱分析：A组Ca/P比为1.61,最接近健康牙本质理论值,Ca/P比高于B、E、F组...     

牙本质保护膜对牙本质小管的封闭作用**

背景：有临床研究报道牙本质保护膜在用于烤瓷全冠牙体预备后牙本质面的保护处理后,能有效降低基牙敏感度。 目的：体外实验观察牙本质保护膜封闭牙本质小管的效果。 方法：将20颗完好离体人前磨牙分为3组：空白对照组牙本质表面不作任何处理,对照组牙本质表面涂布格鲁玛脱敏剂,实验组牙本质表面涂布牙本质保护膜,在扫描电镜下观察牙本质小管口封闭情况。 结果与结论：扫描式电子显微镜观察显示,实验组牙本质小管口密度和直径均明显低于对照组与空白对照组(P < 0.05),牙本质小管口相对面积明显低于空白对照组(P < 0.01)。表明牙本质保护膜在减小牙本质小管的密度和直径方面的作用优于格鲁玛脱敏剂。     

第7代黏接剂与正常和龋损牙本质黏接强度的比较

背景：对于第1~6代牙本质黏接剂的黏接强度,国内外学者做了大量的研究并取得了满意的成果,但尚未见对第7代黏接剂Adper EasyTM one黏接性能的相关报道。 目的：比较3M第7代自酸蚀黏接剂对正常和龋损牙本质黏接强度的差异,并与传统全酸蚀黏接剂进行对比。 方法：取健康磨牙和牙合 面慢性龋磨牙各12颗,分为A、B(健康磨牙),C、D(牙合 面慢性龋磨牙)4组,其中A、C组用Adper EasyTM one黏接剂,B、D组用Single bond 2黏接剂。测试4组试件的微拉伸强度,观察断裂界面形态。 结果与结论：A、B组的黏接强度分别为(21.84±3.98) ,(27.10±4.85) MPa,C、D组的黏接强度分别为(16.44±3.46),(21.48±4.85) MPa,A组与B组、C组与D组、A组与C组、B组与D组之间的微拉伸强度差异均具有显著性意义(P < 0.05)。断裂多发生在树脂-牙本质黏接界面。提示无论在正常牙本质还是龋损影响牙本质,全酸蚀黏接剂的黏接强度强于第7代自酸蚀黏接剂;对于同一种黏接剂正常牙本质能获得比龋损牙本质更大的黏接强度。     

不同瓷表面处理对长石质可切削陶瓷黏结强度的影响

背景：长石质可切削陶瓷作为全瓷材料中不可分割的一种,应用于牙科椅旁CAD/CAM系统,具有精确、快速、高效并且一次就诊等优点,其黏结效果与各种瓷表面处理方法息息相关。 目的：比较不同瓷表面处理对长石质可切削陶瓷的黏结强度的影响。 方法：将切割好的32个Vita MarkⅡ瓷片分为4组：空白组瓷表面无处理;酸蚀组Porcelain Etchant酸蚀40 s,流水冲洗1min后吹干;硅烷偶联剂组使用RelyX Ceramic Primer处理,1 min后吹干;酸蚀和硅烷偶联剂联合组按上述方法酸蚀后涂布硅烷偶联剂,1 min后吹干。每组依次与RelyX Unicem进行黏结。万能材料试验机测其剪切强度,扫描电镜观察黏结界面。 结果与结论：酸蚀和硅烷偶联剂联合组的黏结强度最高,显著高于其余3组(P < 0.05),硅烷偶联剂组黏结强度显著高于酸蚀组与空白组(P < 0.05)。酸蚀和硅烷偶联剂联合组黏结界面最紧密。说明酸蚀和硅烷偶联剂联合应用可提高长石质可切削陶瓷的黏结强度。     

Improvement of the bond strength of 4-META/MMA-TBB resin to collagen-depleted dentin

It has been reported that the tensile bond strength between the 4-META/MMA-TBB resin and dentin pretreated with 10% citric/3% ferric chloride solution decreased after immersion in water for 2 years. The current study investigated the effect of an experimental dentin conditioner on the bonding of 4-META/MMA-TBB resin to dentin after thermocycling. The experimental conditioner was an aqueous solution of 10% ascorbic acid and 5% ferric chloride (Exp). Human teeth were prepared to expose flat dentin surfaces. These were treated sequentially with 40% phosphoric acid, 10% sodium hypochlorite, and the experimental conditioner. A commercially available dentin conditioner, an aqueous solution of 10% citric/3% ferric chloride (10-3) was used for a control group. Stainless steel rods were bonded to the pretreated dentin surfaces with the use of the 4-META/MMA-TBB resin. Tensile bond strengths were determined after 0, 5,000, 10,000, 20,000 themocycles. All data were analyzed by ANOVA, and differences among groups were analyzed by Duncan's new multiple range test (n = 10, p < 0.05). The experimental group showed no significant decrease in bond strength through 20,000 thermocycles, while the control group exhibited significant decrease after 10,000 thermocycles. Mean bond strength of the experimental groups were significantly higher than those of the control group at both 10,000 and 20,000 thermocycles. A hybrid layer could not be identified in SEM micrographs of the experimental groups. 10-3-conditioned specimen SEMs displayed crack formation between the adhesive resin and a hybrid layer. The experimental dentin pretreatment improved the bond strength of a 4-META/MMA-TBB resin to human dentin compared to 10-3 treatment after thermocycling.     

Micro-Raman imaging analysis of monomer/mineral distribution in intertubular region of adhesive/dentin interfaces

It is generally proposed that bonding of resins to dentin results from infiltration of the adhesive monomers into the superficially demineralized dentin. However, it is still not clear how well the mineral phase of dentin is removed and how far each monomer penetrates into the thin zone of "wet" demineralized dentin. The quality and molecular structure of adhesive/dentin interfaces formed under "wet" bonding conditions are studied using 2-D Raman microspectroscopic mapping/imaging techniques. Micro-Raman imaging analysis of the adhesive/dentin interface provides a reliable and powerful means of identifying the degree and depth of dentin demineralization, adhesive monomer distribution, and flaws or defects in the pattern of adhesive penetration. The image of mineral reveals a partially demineralized layer on the top of dentin substrate. Adhesive monomers readily penetrate into dentin tubules and spread into intertubular region through open tubules. The extent of adhesive monomer penetration is higher in the intertubular regions close to tubules as compared to the middle regions between the tubules. The diffusion of resin monomers differs substantially. In a comparison with a hydrophilic monomer, the hydrophobic monomer resists diffusion into the demineralized intertubular dentin area.     

Hybrid layer seals the cementum/4-META/MMA-TBB resin interface

Although 4-META/MMA-TBB resin has adhesive properties to dentin, and has been clinically used for the bonding treatment of vertically fractured roots and apicoectomy, there has not been any investigation on the adhesion of 4-META/MMA-TBB resin to cementum. The purpose of this in vitro study was to evaluate the bonding and the sealing ability of 4-META/MMA-TBB resin to cementum. Bovine root cementum and dentin surfaces were treated with a citric acid and ferric chloride solution, and the 4-META/MMA-TBB resin was applied on the treated surfaces before testing. The microtensile bond strength and the leakage levels obtained for the cementum were almost equal to those for the dentin. In SEM and TEM observations, a hybrid layer approximately 2-3 microm in thickness was observed at the interface between the resin and the cementum. It is concluded that 4-META/MMA-TBB resin adhered to cementum via a hybrid layer on cementum, as previously reported for dentin.     

Polycarboxylated microfillers incorporated into light-curable resin-based dental adhesives evoke remineralization at the mineral-depleted dentin

This study aimed at evaluating the remineralizing properties of three experimental light-curable resin-based dental adhesives containing tailored polycarboxylated microfillers. A co-monomers blend was firstly formulated and then mixed with each of the following microfillers: polycarboxylated bioactive glass (PBAG), polycarboxylated calcium silicates (PCS), and polycarboxylated calcium silicates-doped brushite (PDP). The three experimental and a filler-free control resins were applied onto 10% orthophosphoric acid treated dentin discs and light cured. The specimens were soaked in artificial saliva (AS) for 3, 7, and 14?days. Dentin mineral variation was monitored using attenuated total reflection-Fourier transform infrared (ATR-FTIR) and Raman spectroscopy. Confocal laser scanning microscopy (CLSM) was employed to observe the ultra-morphology/nanoleakage along the resin–dentin interface. The bonding ability and the durability of the resin–dentin bonds were investigated through microtensile bond strength (μTBS) test. ATR-FTIR and Raman showed a significant increase of the mineral matrix area ratio and phosphate peak intensity in specimens treated with the experimental resins within 14?days (p?p?>?0.05). Dentin treated using PBAG or PCS exhibited higher level of remineralization than the specimens in PDP group. CLSM showed reduction in nanoleakage, although the remineralization of the hybrid layer induced a significant drop in the μTBS after 3-month storage (p?相似文献   

Effects of a ferric chloride primer on collagen-depleted dentin bonding between tri-n-butylborane initiated self-curing resin and dentin

This study was designed to evaluate the micro-tensile bond strength between a carboxylic resin and dentin, when the dentin surface was modified with an experimental dentin primer. The three primers tested were ED primer II (ED), 0.3% ferric chloride aqueous solution (FE), and ED containing 0.3% ferric chloride (ED/FE). Three commercial dentin conditioners [40% phosphoric acid, 10% NaOCl, and 10% citric acid with 3% ferric chloride (10-3)] were also used. The coronal surfaces of extracted human molars were ground flat to dentin. The dentin surfaces were treated with phosphoric acid, NaOCl, or with one of the primers. The 10-3 was used without phosphoric acid or NaOCl as a control. A composite material rod was bonded to the dentin surface with 4-META/MMA-TBB resin. After 24-h immersion in 37 degrees C distilled water, 0.9 mm x 0.9 mm composite-dentin beams cut from the bonded specimens were stressed to failure in tension at 0.6 mm/min. The bond strengths were also evaluated after 5000 thermocycles. The bond strength of the group ED/FE was significantly higher than those of the 10-3, ED, and FE. After 5000 thermocycling, 10-3, ED and FE showed significant decrease in bond strength, although no significant decrease was seen for ED/FE. It was concluded that dentin surface treatment with phosphoric acid, NaOCl, and the ED/FE primer improved the bonding (p < 0.05) between 4-META/MMA-TBB resin and dentin, with or without thermocycling, while the bond strengths in the control group fell 34% following 5000 thermocycles.     

Effect of self-etching primers containing N-acryloyl aspartic acid on dentin adhesion

The purpose of this study was to evaluate the feasibility of aspartic acid derivative, N-acryloyl aspartic acid (N-AAsp) when used as a self-etching primer prior to the application of a commercial bonding agent containing 10-methacryloxydecyl dihydrogen phosphate. N-AAsp was synthesized by the reaction of DL-aspartic acid and acryloyl chloride. N-AAsp can be dissolved in water up to 25 wt % and can adequately remove the smear layer. When 20 wt % N-AAsp was applied as a self-etching primer, the tensile bonding strength of resin composite to dentin doubled to 16.0 MPa compared with that of the nonetching group or the 40 wt % H(3)PO(4) etching/water rinse group. Scanning electron microscopic observations revealed that the formation of the hybrid layer at the interface between the resin composite and dentin and the thickness of the hybrid layer increased with N-AAsp concentration. The hybrid layer in the specimens treated with 20 wt % N-AAsp aqueous solution presented a uniform structure, whereas those treated with 5 wt % N-AAsp solution showed a porous structure. We conclude that 20 wt % N-AAsp aqueous solution has good potential value as a self-etching primer.