乙醇润湿对牙本质粘接界面渗透性的影响

目的 研究牙本质疏水性粘接前乙醇润湿对粘接强度和粘接界面渗透性的影响,以期更好地为临床提供指导.方法 24颗无龋第三磨牙去除冠部釉质后暴露中层牙本质,利用随机数字表随机分成6个组(每组4颗).所有操作过程均在模拟髓腔压力的情况下进行,对照组采用全酸蚀粘接剂( Adper Scotchbond Multi-Purpose)粘接;4个实验组分别用无水乙醇润湿牙面20 s、1min、2 min、3min,1个实验组使用梯度乙醇润湿牙面,5个实验组采用实验室配制的疏水性粘接剂粘接.固化24h后进行微拉伸强度检测,计算粘接强度.荧光染料罗丹明B于牙髓腔中荷载3h后采用激光扫描共聚焦显微镜观察粘接界面的渗透情况.结果 与对照组相比,乙醇润湿20 s组和1min组粘接强度[(21.02±7.23) MPa和(29.64±3.81) MPa]均显著低于对照组[(38.14±4.97) MPa],差异有统计学意义(P＞0.05);而乙醇润湿2 min组[(38.40 ±5.03) MPa]、3min组[(37.26±4.68)MPa]和梯度乙醇润湿组[(40.12±5.95) MPa]的粘接强度与对照组接近,差异无统计学意义(P＜0.05).激光扫描共聚焦显微镜观察显示,随着乙醇润湿时间的延长,荧光染料在混合层和牙本质小管侧壁的沉积逐渐减轻,其中梯度乙醇润湿组仅在混合层附近检测到少量荧光染料.结论 在模拟髓腔压力的情况下,2 min以上的乙醇润湿结合疏水性粘接剂可获得良好的粘接力,同时明显降低粘接界面的微渗透.     

乙醇润湿对2种全酸蚀粘接剂粘接性能的影响

目的:探究牙本质粘接前用乙醇润湿对临床常用2种全酸蚀粘接剂粘接强度和粘接界面质量的影响。方法:24颗新鲜拔除人无龋磨牙随机分为6组,2种粘接剂Single Bond(SB)、Gluma Comfort Bond(GB),每种分成3组用不同方法粘接即:对照组(粘结剂常规应用组)、乙醇润湿1min组、乙醇润湿2min组。每组牙制作微拉伸试件,测试24h微拉伸粘接强度(MTBS),用体视显微镜观察断面类型。用扫描电镜观察粘接界面混合层和树脂突形态。结果:乙醇润湿2min的方法使以上两种粘接剂的24h瞬时微拉伸强度(MTBS)显著提高;而乙醇浸润1min的效果与对照组无统计学差异。SEM观察结果也提示乙醇润湿2min能够显著改善粘接界面混合层的质量、增加树脂突的数量以及长度;乙醇1min可以增加树脂突长度,但对数量无明显影响。结论:乙醇润湿2min对2种粘接剂的粘接性能有显著改善。     

过硼酸钠内漂白对牙本质与树脂粘接强度影响的实验研究

目的比较牙本质经过硼酸钠漂白后在不同时间粘接树脂,其抗剪强度变化及粘接界面的超微形态。方法18颗恒前磨牙随机分为3组。A组为对照组：人工唾液内3周后制备牙本质粘接面,粘接树脂。B组：牙齿漂白3周后制备牙本质粘接面,粘接树脂;C组：牙齿漂白3周,人工唾液内储存2周后制备牙本质粘接面,粘接树脂。电子万能材料实验机测试抗剪粘接强度;扫描电镜观察粘接界面超微形态。结果①抗剪强度测试结果：A组：18.61±3.56MPa;B组：12.10±2.64MPa;C组：16.78±2.84MPa。②统计学分析：单因素方差分析表明三组样本均数之间存在统计学差异（P〈0.05）。各样本均数的两两比较（SNK-q法）结果显示A与B组,B与C组的抗剪强度值差别有统计学意义（P〈0.05）,而A与C组的抗剪强度值之间无统计学差异（P〉0.05）。③粘接界面的SEM观察结果：A组粘接界面上可见大量的树脂突渗入牙本质小管内,树脂突的长度较长并且均匀。B组粘接界面上的树脂突稀少,长度较短并且长短不一。C组粘接界面可见有较多的树脂突,长度均匀但较为短小。结论过硼酸钠漂白后牙本质的粘接时间对牙本质与树脂的粘接强度有影响：牙齿漂白后即刻粘接树脂,会降低牙本质与树脂的粘接强度,而漂白后延迟2周再粘接树脂能够恢复牙本质与树脂的粘接强度。     

硬化牙本质粘接界面的激光扫描共聚焦显微镜观察

目的使用激光扫描共聚焦显微镜（CLSM）观察牙颈部硬化牙本质在全酸蚀和自酸蚀粘接系统形成粘接界面的超微结构。方法选用12颗因牙周病拔除的具有典型楔状缺损的上颌前磨牙为实验组;12颗新鲜拔除的无龋人上颌前磨牙为对照组,制备人造楔状缺损。使用Single Bond （SB,全酸蚀单瓶系统）、Clearfil SE Bond（CB,自酸蚀底胶系统）、Xeno Ⅲ（XB,自酸蚀一步粘接系统）粘接系统处理牙面,以罗丹明B异硫氰酸盐为荧光素,使用CLSM观察粘接界面的混合层与树脂突的微观结构。结果双因素方差分析表明粘接剂种类、牙本质类型对粘接界面树脂突长度、混合层厚度有显著影响（P<0.05）。无论是正常牙本质还是硬化牙本质,全酸蚀粘接剂（SB）产生的树脂突长度、混合层厚度均大于自酸蚀粘接剂（CB、XB）,并且其差异具有统计学意义（P<0.05）;而CB和XB间树脂突长度、混合层厚度相差不多,二者间无统计学意义。结论硬化牙本质相对于正常牙本质形成的混合层较薄或者没有,树脂突短、少。全酸蚀粘接系统与自酸蚀粘接系统作用同类型的牙本质上,自酸蚀比全酸蚀形成的混合层薄,树脂突短。     

葡萄籽提取物对脱矿牙本质极限拉伸强度及树脂-牙本质粘接强度的影响

目的:探讨葡萄籽提取物(grape seed extract,GSE)短暂预处理脱矿牙本质对其极限拉伸强度及树脂-牙本质即刻微拉伸粘接强度的影响。方法:以乙醇、丙酮、蒸馏水为溶剂配制不同浓度的GSE溶液,以溶剂为空白对照,无预处理为阴性对照,5%戊二醛为阳性对照,每组样本15例。GSE预处理脱矿牙本质后,测试牙本质极限拉伸强度及树脂-牙本质微拉伸粘接强度,观察粘接断裂面微观形貌并分析断裂模式。结果:GSE预处理组牙本质极限拉伸强度均呈浓度和时间依赖性增加。应用Single Bond 2粘接时,无论何种溶剂,10%或15%GSE预处理组微拉伸粘接强度显著高于空白对照组(P<0.05);而用Prime&Bond NT粘接时,仅15%GSE水溶剂组和10%GSE丙酮溶剂组微拉伸粘接强度显著高于空白对照组(P<0.05)。交联预处理对水和乙醇溶剂的Single Bond 2粘接时微拉伸粘接强度的改善作用比用水和丙酮溶剂的Prime&Bond NT粘接时更为显著。粘接试件断裂均以混合破坏为主,预处理组试件断裂多发生在混合层顶部,而阴性和空白对照组断裂多位于混合层底部。结论:GSE短暂预处理脱矿牙本质可改善其机械性能,增强混合层,并提高树脂-牙本质即刻微拉伸粘接强度。     

丙酮基和酒精-水基牙本质粘接系统粘接强度比较及粘接界面观察

目的:比较丙酮基和酒精-水基两种不同溶剂类型的全酸蚀牙本质粘接系统粘接强度和粘接界面的微观形态。方法:选择24颗正畸治疗拔除的健康前磨牙,去除合面釉质层,随机分两组,每组选用一种 “两步法”全酸蚀牙本质粘接系统:以丙酮为溶剂的Prime & Bond NT(PB组)和以酒精和水为溶剂的Single Bond 2(SB2)组,粘接后进行微拉伸力检测。以扫描电镜(SEM)和激光共聚焦扫描电镜(LCSM)观察两种牙本质粘接系统的粘接界面。结果:粘接强度PB组(29.49±4.01) MPa,SB2组微拉伸粘接强度为,SB2组为(30.03±4.33) MPa,无统计学差异。两种牙本质粘接系统均可充分渗入脱矿牙本质表层的胶原纤维网和牙本质小管内,形成混合层和树脂突,SB组混合层薄而均匀,树脂突长。结论:不同溶剂类型的两组牙本质粘接系统微拉伸粘接强度无差异,全酸蚀牙本质粘接系统在湿粘接状态下可以对牙本质形成良好的渗透。     

渗透树脂与流体树脂封闭牙本质小管的实验研究

目的：观察渗透树脂与流体树脂在自酸蚀粘接及全酸蚀粘接条件下对暴露牙本质小管的封闭效果。方法：将60颗健康离体牙随机分为4组（n ＝15）,在不同粘接条件下对暴露的牙本质进行粘接,A 组采用 Icon-Etch 酸蚀,渗透树脂 Icon-In-filtrant 粘接;B 组采用 SE-Bond 酸蚀粘接,Icon-Infiltrant 粘接;C 组采用 SE-Bond 酸蚀粘接,流体树脂 Filtek TMZ350XT 粘接;D组采用格鲁玛酸酸蚀,Prime ＆Bond NT 和 FiltekTMZ350XT 粘接,扫描电镜观察各组树脂粘接面形态,测量混合层、粘接剂层的平均厚度及树脂突的平均长度。结果：渗透树脂与流体树脂一样在暴露牙本质表面形成紧密嵌合,D 组混合层厚度最厚,C组的粘接剂层最厚,而 A 组渗入到牙本质小管中的树脂突最长,有统计学差异（P ＜0．05）。结论：渗透树脂可渗透入暴露的牙本质小管形成树脂突,封闭牙本质小管,其作用优于自酸／全酸粘接的流体树脂。     

原花青素联合乙醇湿粘结技术对乳牙牙本质剪切粘结强度的影响

目的：观察原花青素（PA）联合乙醇湿粘结技术对树脂乳牙牙本质剪切粘结强度的影响。方法：选取乳磨牙35颗,沿近远中向劈开,制成70个样本。将实验牙随机分为5组,分别为PA＋乙醇溶液预处理60 s和120 s组;乙醇单独预处理60 s和120 s组;对照组的牙本质树脂粘结试件。电子万能试验机测定37℃水浴保存24 h和30 d的剪切粘结强度;扫描电镜观察断裂面形态。结果：PA＋乙醇预处理组剪切粘结强度值明显大于乙醇单独预处理组和对照组（P＜0．05）,FESEM观察结果显示PA＋乙醇预处理组断裂主要发生在混合层顶部。结论：原花青素和乙醇湿粘结技术联合使用可以提高树脂乳牙牙本质间的剪切粘结强度。     

牙颈部非龋性硬化牙本质粘接的超微形态研究

目的观察牙颈部非龋性硬化牙本质经自酸蚀牙本质粘接剂处理后，树脂一牙本质界面的超微结构。方法选择有典型牙颈部非龋性缺损且因牙周病拔除的上颌前磨牙，使用两步法的自酸蚀粘接剂Contax粘接处理。扫描电镜观察硬化牙本质表面超微形态以及树脂一牙本质界面的混合层和树脂突的微观表现。结果硬化牙本质的牙本质小管大部分被柱状的矿化结晶体堵塞。粘接界面也可见到清晰的混合层和树脂突，但树脂突较短。结论硬化牙本质的粘接与正常牙本质存在差异，牙本质小管内的矿化结晶可能影响粘接效果。自酸蚀粘接剂对硬化牙本质具有一定的粘接能力。     

两种树脂水门汀对纤维桩冠方微渗漏的影响

目的：通过观察两种树脂水门汀引起的纤维桩冠方微渗漏值及在扫描电镜下与牙本质的粘接界面,比较两种树脂水门汀的封闭性能。方法：42颗离体下颌前磨牙分成6组,其中30颗牙分为2组,分别用Panavia F、Paracore 5mL粘接纤维桩,经染色、透明化处理后,在体式显微镜下记录2组微渗漏得分;另有10颗牙分为2组,分别用Panavia F、Paracore 5mL粘接纤维桩后纵形剖开,置于扫描电镜下观察牙本质水门汀界面;其余2颗牙分别作为阳性对照组及阴性对照组。结果：Paracore 5mL引起的纤维桩冠方渗漏值明显较Panavia F小（P〈0.01）。两种树脂水门汀与牙本质界面均可形成混合层,而仅Paracore 5mL组可发现树脂突及粘接性侧枝。结论：全酸蚀树脂水门汀对纤维桩冠方微渗漏的影响较自酸蚀树脂水门汀小;全酸蚀树脂水门汀与牙本质结合紧密,封闭性能较自酸蚀树脂水门汀优越。     

Tubular occlusion optimizes bonding of hydrophobic resins to dentin

Although hydrophobic resins may be bonded to acid-etched dentin with an ethanol wet-bonding technique, the protocol is sensitive to moisture contamination when bonding is performed in deep dentin. This study tested the hypothesis that the use of oxalate or poly(glutamic) acid-modified, diluted ceramicrete (PADC) for dentinal tubule occlusion prevents fluid contamination and improves the bonding of an experimental hydrophobic adhesive to acid-etched, ethanol-dehydrated dentin. Mid-coronal and deep acid-etched moist dentin pre-treated with oxalate or PADC was dehydrated by ethanol wet-bonding and infiltrated with the experimental three-step etch-and-rinse hydrophobic adhesive under simulated pulpal pressure. Tensile bond strengths to deep dentin without pre-treatment were severely compromised. Conversely, oxalate and PADC pre-treatments reduced dentin permeability, prevented water contamination, and improved bond strengths. Minimal nanoleakage was identified within hybrid layers created in the oxalate- and PADC-pre-treated deep dentin. The use of tubular occluding agents optimized bonding of hydrophobic resins to dentin.     

The Efficacy of Different Sealer Removal Protocols on Bonding of Self-etching Adhesives to AH Plus–contaminated Dentin

IntroductionSmearing of unset root canal sealers over the pulp chamber dentin may adversely affect bonding of self-etching adhesives and jeopardize their coronal sealing potential. This study examined the influence of different sealer removal protocols on the microtensile bond strengths of two self-etching adhesives to AH Plus-contaminated dentin.MethodsCoronal dentin surfaces were prepared from extracted human third molars. In the positive control groups, these surfaces were not contaminated with sealer and were bonded with Clearfil SE Bond or Clearfil Tri-S Bond. For the experimental groups, dentin surfaces were contaminated with AH Plus and wiped with either dry cotton pellets, cotton pellets saturated with ethanol, or cotton pellets saturated with Endosolv R followed by rinsing the dissolved sealer with water prior to bonding with the two adhesives. Bonded specimens were sectioned into resin-dentin beams for microtensile bond strength evaluation. Additional specimens were prepared for transmission electron microscopy to examine the ultrastructure and nanoleakage within the hybrid layers.ResultsFor both adhesives, microtensile bond strengths significantly declined when the sealer was removed with dry cotton pellets or cotton pellets saturated with ethanol. Only the Endosolv R/water sealer removal protocol restored tensile bond strengths to those of the uncontaminated positive controls without adversely affecting hybrid layer formation in intact dentin or increasing nanoleakage within the resin-dentin interfaces.ConclusionThe Endosolv R sealer removal protocol appears to be effective in preventing the deterioration of bond strengths of the two self-etching adhesives to AH Plus–contaminated dentin and warrants further clinical investigation.     

Bonding BisGMA to dentin--a proof of concept for hydrophobic dentin bonding

The use of TEGDMA as a diluent comonomer in the formulation of hydrophobic adhesives for ethanol wet-bonding is a concern, due to its leaching potential, higher water sorption, and bio-incompatibility. This study tested the hypothesis that hydrophobic bonding to acid-etched dentin may be accomplished with the use of ethanol-solvated BisGMA only. Phosphoric-acid-etched, oxalate-occluded, deep coronal dentin bonded under 20 cm water pressure with experimental BisGMA adhesives by ethanol wet-bonding exhibited tensile strengths that were not significantly different from that achieved with OptiBond FL bonded according to the manufacturer-recommended protocol, with similar acid-/base-resistant hybrid layers, resin tags, and nanoleakage distribution. Ethanol replacement of water-saturated dentin produced wider interfibrillar spaces, more extensive shrinkage of the collagen fibrils, and narrower hybrid layers. Experimental BisGMA adhesives provide the proof of concept that relatively hydrophobic resins may be coupled to acid-etched dentin by increasing its hydrophobic characteristics via ethanol replacement. They should be further optimized before clinical application.     

Bonding to root caries by a self-etching adhesive system containing MDPB

PURPOSE: To evaluate the bonding of an experimental antibacterial fluoride-releasing adhesive system (ABF) to normal and carious dentin in human teeth with Class V root caries. METHODS: Mesiodistal sectioning removed the buccal enamel, superficial dentin and much of the carious dentin in 21 extracted human bicuspids with root surface caries. The surfaces of normal coronal and root dentin, and caries-affected and caries-infected dentin were ground with wet 600-grit SiC paper to create a standardized smear layer. Tooth surfaces were treated with the ABF according to manufacturer's instructions, and then covered with excess resin composite. After immersion in 37 degrees C water for 24 hours, the restored teeth were horizontally sectioned into serial slabs that were trimmed into hourglass shapes to isolate the bonded area to the test substrates, and then their bond strengths were measured by the microtensile bond test, and the interfaces examined by SEM and TEM. The bond strengths were statistically compared with ANOVA and Fisher's PLSD (P < 0.05). RESULTS: The bond strengths of ABF to caries-affected and caries-infected dentin were significantly lower than those to normal coronal and root dentin. SEM micrographs revealed that the hybrid layers in caries-affected and caries-infected dentin were more porous compared to the hybrid layer in normal coronal and root dentin. TEM micrographs showed that bacteria that had invaded the dentin were embedded in this adhesive monomer in caries-infected dentin. CLINICAL SIGNIFICANCE: Although the bond strength of ABF adhesive system to root carious dentin is lower than that of normal dentin, the antibacterial and fluoride-releasing properties of ABF may contribute to prevent caries progression and inhibit secondary caries.     

Effects of resin hydrophilicity on dentin bond strength

The purpose of this study was to determine if hydrophobic resins can be coaxed into dentin wet with ethanol instead of water. The test hypothesis was that dentin wet with ethanol would produce higher bond strengths for hydrophobic resins than would dentin wet with water. This study examined the microtensile bond strength of 5 experimental adhesives (50 wt% ethanol/50% comonomers) of various degrees of hydrophilicity to acid-etched dentin that was left moist with water, moist with ethanol, or air-dried. Following composite buildups, hourglass-shaped slabs were prepared from the bonded teeth for microtensile testing. For all 3 types of dentin surfaces, higher bond strengths were achieved with increased resin hydrophilicity. The lowest bond strengths were obtained on dried dentin, while the highest bond strengths were achieved when dentin was bonded moist with ethanol. Wet-bonding with ethanol achieved higher bond strengths with hydrophobic resins than were possible with water-saturated matrices.     

简化乙醇湿粘结对龋影响牙本质粘结强度的影响

目的:评估简化乙醇湿粘结技术对龋影响牙本质粘结强度的影响。方法:选取人慢性龋离体第三磨牙36颗去龋备洞后保留龋影响牙本质。随机分为6组,分别使用自制疏水性粘结剂,Prime & Bond NT(PB),Adper Single bond plus(SB)进行粘结,堆砌树脂厚度约4~5 mm。实验组采用简化乙醇湿粘结法,对照组采用传统水湿粘结法。制作1 mm ×1 mm ×8 mm的条形微拉伸强度试件,每组选取8个。采用万能材料试验机测试微拉伸强度并记录,观察断裂界面。结果:在自制疏水性粘结剂组中,实验组粘结强度较对照组有显著提高(P<0.05)。结论:简化乙醇湿粘结技术可以提高CAD界面的粘结强度,尤其是在与疏水性粘结剂联合运用时,有显著提高。     

冷热循环对牙本质粘结耐久性的影响

目的:研究冷热循环对牙本质粘结强度和粘结界面纳米渗漏的影响.方法:选取30个无龋损人磨牙,用600目碳化硅砂纸在流水冲洗下预备牙本质粘结面,分别用3种(Prime&Bond NT,Adper Prompt和Contax)粘结剂进行粘结处理,复合树脂充填.纵向片切牙齿,制备粘结面积为1 mm2的条形树脂牙本质试样.冷热循...     

Bonding ability of adhesive resins to caries-affected and caries-infected dentin

Hybridized dentin permits dental treatments that were previously impossible with conventional techniques, opening new frontiers in modern adhesive dentistry. We have investigated the adhesive property of current bonding systems to caries-infected dentin by a microtensile bond strength test (μTBS) and transmission electron microscopy (TEM), and suggested that bonding resin could infiltrate into caries-infected dentin partially to embed carious bacteria within hybrid layers. We have named this concept of caries control as modified sealed restoration (MSR). On the other hand, Kuraray Medical Inc. (Tokyo, Japan) has developed an antibacterial adhesive system (ABF, now marketed in USA as Protect Bond). So as to evaluate the effectiveness of ABF on root caries control, we have examine the microtensile bond strengths (μTBS) of ABF to normal versus carious root dentin and the interfacial morphology by a scanning electron microscopy (SEM). ABF could form the hybrid-like structures by infiltrating into the surfaces of the root carious dentin, and the mean value of μTBS of ABF to root carious dentin was 23.0 MPa. These results suggested that MSR combined with ABF might be an advantageous minimal invasive therapy for root caries.     

Bonding of self-etch and total-etch adhesives to carious dentin

Carious dentin is partially demineralized and contains mineral crystals in the tubules. This may permit the deeper etching of intertubular dentin but prevent resin tag formation during bonding. We hypothesize that resin adhesives will produce lower bond strengths to caries-infected and caries-affected dentin compared with normal dentin. We tested this by measuring the microtensile bond strength of a total-etch adhesive and an experimental self-etching adhesive (ABF) to caries-infected, caries-affected, and sound dentin and by correlating those results with ultrastructural observations. The bond strengths of both adhesives to sound dentin were significantly (p < 0.05) higher than those to caries-affected dentin, which, in turn were significantly (p < 0.05) higher than those to caries-infected dentin. For both adhesives, hybrid layers in caries-affected dentin were thicker but more porous than those in sound dentin. The lower bond strengths may be due to the lower tensile strength of caries-affected dentin. Clinically, this may not be a problem, since such lesions are normally surrounded by normal dentin or enamel.