Er:YAG激光和Nd:YAG激光辅助的牙漂白对树脂充填体粘接强度和边缘微渗漏的影响

目的：评价Er:YAG激光和Nd:YAG激光辅助的牙漂白对釉质表面树脂充填体粘接强度和边缘微渗漏的影响。方法：将离体牙制备成釉质测试试件（n=64）后随机分为4组（n=16），包括对照组、传统漂白组、Er:YAG激光辅助的漂白组和Nd:YAG激光辅助的漂白组。4组试件分别处理后，检测其釉质表面树脂充填体的剪切粘接强度（n=8）和微渗漏深度（n=8），利用体视显微镜观察各组试件的断裂模式。采用SPSS 26.0软件包对数据进行统计学分析。结果：与对照组相比，传统漂白后釉质表面树脂充填体的粘接强度显著下降，边缘微渗漏显著增加(P<0.05);Er:YAG激光辅助的漂白后釉质表面充填体的剪切粘接强度和微渗漏深度与对照组相比无显著差异（P>0.05）,Nd:YAG激光辅助的漂白后树脂充填体的剪切粘接强度显著下降（P<0.05），但其边缘微渗漏深度与对照组相比无显著差异(P>0.05)。4组试件的粘接断裂模式主要为粘接界面断裂。结论：相比传统漂白方法，激光辅助的牙漂白对树脂充填体粘接强度和微渗漏的影响较小，具有一定的临床优势。     

四种常用牙本质粘结剂的边缘封闭性比较

目的对比研究四种临床常用牙本质粘结剂的边缘封闭性能.方法在20个离体人恒磨牙颊、舌侧牙颈部各制备3 mm×2 mm×2 mm的箱型V类洞.制备的窝洞随机分为4组,分别以全酸蚀粘结剂Prime&BondNT和Single Bond,自酸蚀粘结剂Adper Prompt和Clearfil SE Bond粘结,Charisma复合树脂充填.0.5%碱性品红溶液中染色24 h后,将充填体连续纵向剖开为四部分,体视显微镜下观察各剖面充填体边缘的微渗漏情况,并以扫描电镜观察树脂-牙本质界面的结合状态.结果各种粘结剂均存在微渗漏现象,龈方微漏程度显著高于冠方(P＜0.05).各种粘结剂之间的微漏程度无显著性差异(P＞0.05).电镜下各组界面均存在散在间隙,全酸蚀粘结剂形成的混合层较自酸蚀者厚,树脂突亦较长.结论多剖面评分法较常规正中剖面法能更全面地评价界面的微漏情况;各种粘结剂均不能完全消除充填体边缘微漏.     

粘结技术对银燕合金充填体边缘微波的影响

目的研究粘结技术对银汞合金充填体边缘微漏的影响。方法将制备洞型后的４０颗离体牙髓机分为二组，一组采用粘结技术法充填银汞，另一组按常规充填银汞，所有标本均进行染料渗透试验，观测染料渗漏情况，并在ＳＥＭ下测量充填体与牙体间的微缝隙宽度。结果粘结组染料渗漏的例数少、程度轻，其微漏明显小于对照组（Ｐ〈０．０１）；扫描电镜观察发现，粘结组充填体边缘缝隙宽度明显小于对照组（Ｐ〈０．０１）。结论采用粘结技术可以明显减少银汞合金充填体的边缘微漏。     

脉冲Nd:YAG激光照射牙本质后对光固化树脂充填体边缘微渗漏的影响

目的研究脉冲Nd：YAG激光照射牙本质后对光固化树脂充填体边缘微渗漏的影响，以探讨脉冲Nd-YAG激光在龋病治疗中的临床应用意义。方法选用正畸要求拔除的正常双尖牙30颗，随机分为A。B，C三组，每组10颗，用高速裂钻备洞（洞长、宽为3mm；洞深为2mm），A组为对照组，常规酸蚀树脂充填；B，C两组分别用50mJ，10Hz和100mJ，10Hz的脉冲Nd：YAG激光能量照射窝洞牙本质壁30s后树脂充填，分别用体视显微镜和扫描电镜观察充填体边缘和洞壁结合情况。结果．体视显微镜下观察：A组的牙本质洞壁与光固化树脂充填体间染料渗入较多，着色较深；B、C组的牙本质洞壁与光固化树脂充填体间染料渗入较少，着色较浅。扫描电镜下观察：B、C组的牙本质洞壁与光固化树脂充填体间裂隙明显小于未经激光处理的对照组。结论脉冲Nd：YAG激光处理牙本质后进行光固化复合树脂充填，可以减少充填体微渗漏，有利于充填的成功．     

两步法酸蚀-冲洗粘结剂对脱胶原蛋白牙本质的粘结

目的：评估XP-Bond与人脱蛋白牙本质粘结即刻和人工老化6个月后粘结界面的微拉伸粘结强度和纳米渗漏的表现。材料和方法：选择成人无龋磨牙．暴露中深层牙本质．分为组1（XP—Bond与脱蛋白的牙本质粘结）和组2（按照生产商的说明使用XP—Bond）。在组1中．酸蚀牙本质表面后．用10％次氯酸钠处理60s以去除暴露的已脱矿的有机基质，再与XP—Bond粘结。树脂／牙本质柱采用无缝微拉伸技术，24h或人工老化6个月后被拉伸至断裂。数据分析使用two—way ANOVA和Tukey＇s post—hoc检测（P〈005）。通过在粘结界面上定量检测银示踪剂的量来评价界面的纳米渗漏。结果：在XP—Bond粘结前使用次氯酸钠处理组的即刻粘结强度[组1：（18．9±58）MPa]比对照组降低62％[组2：（49.9±103）MPa；P〈05]。人工老化6个月后．组1和组2的粘结强度分别显著降低到（10．1±2．7）MPa和（35.2±8．7）MPa（P〈0.05）。应用次氯酸钠和人工老化均会使XP—Bond粘结界面的纳米渗漏增加。结论：脱胶原的牙本质即刻粘结强度和长期的粘结稳定性均有所降低，提示胶原纤维对牙本质的粘结起着重要的作用。     

树脂类粘结剂边缘厚度对全瓷冠边缘微渗漏的影响

目的：研究树脂类粘结剂边缘厚度与全瓷冠边缘微渗漏的相关关系。方法：16颗上颌第三磨牙经标准牙体制备，制作IPS－Empress 2全瓷冠，分两组用多组份树脂粘结剂和自炽结多聚酸改性树脂炽结剂粘固，经温度循环试验后，用扫描电镜测量边缘粘固剂厚度，再将样本浸入2％品红溶液24小时，系列切片，用体视显微镜观测边缘微渗漏程度。结果；两种树脂粘结剂边缘粘固剂厚度与牙－粘固剂界面和全瓷冠－粘固剂界面边缘微渗漏程度均无相关关系（P＞0．05）。结论：树脂类粘结剂边缘粘固剂厚度若在理想的临床要求范围内，不足以影响全瓷冠边缘微渗漏程度。     

过氧化氢酶对外漂白后树脂充填体边缘微渗漏的影响

目的： 观察过氧化氢酶对10%过氧化脲外漂白后复合树脂充填体边缘微渗漏的影响。方法： 选取牙体健康完整的人离体前磨牙40颗,随机分为4组,第1组不漂白直接进行树脂充填,第2组外漂白后立即树脂充填,第3组外漂白后将牙在人工唾液中浸泡3周再进行树脂充填,第4组外漂白后先用过氧化氢酶处理窝洞再进行树脂充填。然后将4组样本进行2000个周期的冷热循环,应用2%亚甲基蓝染色24 h,体视显微镜下观察剖面树脂充填体的微渗漏程度,采用SPSS17.0软件包对数据进行统计学分析。结果： 第1组微渗漏值最低,第2组微渗漏值最高,第3组微渗漏值显著高于第1组但与第2组相比无显著差异（P>0.05）;第4组微渗漏值较第2组显著下降（P<0.05）。结论： 10%过氧化脲外漂白致树脂充填体边缘微渗漏明显增加,树脂充填前应用过氧化氢酶处理窝洞,可有效减少微渗漏,延迟充填不能有效改善微渗漏。     

四种双固化树脂粘结剂与根管牙本质间微渗漏的研究

目的评价冷热循环对4种双固化树脂粘结剂与根管牙本质间微渗漏的影响。方法20颗健康上前牙随机分为4组。根管预备后选用4种粘结树脂及其配套粘结剂（Clearfil DC Core Automix,Calibra esthetic resincement,DMG LUXACORE Smartmix Dual,3M ESPE RelyX^TM Unicem）分别粘结直径1．2mm树脂纤维桩,并用此4种材料分别做树脂核。将试件冷热循环处理10000次（温度设定为4℃／60℃,浸泡时间30s,传递时间20s）后,用0．5％碱性品红溶液染色24h。将试件连续纵向剖开为四部分,体视显微镜下观察各剖面的微渗漏情况,并用Kmskal-WaillisH非参数检验进行统计分析。结果各种树脂粘结剂均存在微渗漏现象,各种粘结剂之间的微漏程度有显著性差异（P〈0．05）。结论冷热循环后4种双固化树脂粘结剂粘结纤维桩与根管牙本质之间均存在微渗漏现象,使用Clearfd DC Core Automix作为粘结树脂的试件微渗漏程度最轻。     

不同表面粒度车针预备所致玷污层对牙本质粘结强度的影响

目的：比较两种不同表面粒度的金刚砂车针进行牙体预备后对牙本质粘结强度的影响。方法：采用两种金刚砂车针与碳化硅砂纸对牙本质表面进行打磨预备后，分别选用全酸蚀粘结剂Single Bond及自酸蚀粘结剂iBond与树脂粘结，用慢速切割机片切牙齿，精细金刚砂车针修成沙漏状的粘接面积约0．8mm^2的样本，测试各个样本的微拉伸粘结强度。结果：全酸蚀粘结条件下，3组样本的粘结强度无显著差异，而在应用自酸蚀粘结剂时，粗粒度车针预备后的牙本质粘结强度明显低于经极细粒度车针或是碳化硅砂纸处理组（P〈0．05）。结论：采用极细粒度车针进行牙体预备可以有效增强牙本质与自酸蚀粘结剂间粘结强度。     

几种市售商品充填材料密合度的实验研究

选用几种市售牙体充填复合树脂和玻璃离子水门汀充填Ⅴ类洞(龈壁由牙骨质和牙本质组成),采用染色法观察其边缘微漏的离体牙实验。发现不同充填材料存在不同程度的边缘微漏,酸处理洞缘可显著降低边缘微漏(P<0.05),窝洞的牙釉质壁渗漏显著低于牙骨质壁渗漏(P<0.01)。实验结果提示,充填材料的粘附性能,窝洞边缘的位置以及酸处理技术,都将影响牙体充填的治疗效果。     

Effect of dentin deproteinization on microleakage of Class V composite restorations

The role of the collagen fibers in dentin adhesion has not clearly been established. Therefore, this laboratory study evaluated the microleakage at resin-dentin and resin-enamel interfaces of Class V composite restorations after etching enamel and dentin with phosphoric acid (H3PO4) or after etching with H3PO4 followed by deproteinization with 5% sodium hypochlorite (NaOCl) to prevent the formation of a hybrid layer. Ten extracted human molars were used to prepare standardized Class V cavities on both buccal and lingual surfaces. The teeth were randomly divided in two groups: 1) Class V cavities that were etched with H3PO4 for 15 seconds; b) Class V cavities that were etched with H3PO4 for 15 seconds followed by collagen removal with 5% NaOCl for two minutes. The cavities were restored using the Prime & Bond 2.1 bonding system and TPH resin composite. The specimens were stored in water for 24 hours at 37 degrees C and thermocycled 500 times between water baths kept at 5 degrees C and 55 degrees C. After thermocycling, specimens were immersed in a 0.5% aqueous solution of basic fuchsin for 24 hours. Three longitudinal sections of each restoration were obtained and examined with a stereomicroscope for qualitative evaluation of microleakage. The data were statistically analyzed by Mann-Whitney U and Wilcoxon matched pairs signed ranked tests. Extra specimens were analyzed with the scanning electron microscope (SEM). Occlusal margins (enamel margins) resulted in statistical lower degree of leakage than gingival margins (dentin/cementum margins) in both treatment groups. For each type of margin, there were no statistically significant differences between the etched and the etched and deproteinized groups. Under the SEM, occlusal surfaces showed no detachment between enamel and dentin, while dentin/cementum resulted in gap formation.     

Er：YAG激光制备窝洞对树脂充填微渗漏的影响

目的应用离体牙比较复合树脂与Er：YAG激光及传统牙钻制备窝洞洞壁间微渗漏的差异。方法将30颗前磨牙随机分为3组,每组10颗牙,制备Ⅴ类洞：Ⅰ组牙钻预备加酸蚀处理;Ⅱ组单纯激光预备组、Ⅲ组激光预备加酸蚀处理组,经冷热循环染色后,在体视显微镜下记录微渗漏程度并应用非参数统计方法分析数据。结果各组内颈壁的染料渗透情况均比壁明显（P〈0.05）;在壁,单纯激光预备组产生的微渗漏最严重（P〈0.05）,激光预备加酸蚀处理组与牙钻预备加酸蚀处理组微渗漏无统计学差异;在颈壁,三组充填体边缘微渗漏情况无统计学差异。结论Er：YAG激光可代替牙钻备洞,结合酸蚀处理与充填体有良好的密合度。     

Early marginal microleakage in class II resin composite restorations

The aim of this study was to evaluate in vitro the early marginal microleakage around conventional and sandwich Class II (MOD) restorations. Ten different combinations of dentin bonding agents, glass-ionomer cements, and posterior resin composites were used. Class II cavities were prepared in freshly extracted third molars whose root surfaces had previously been coated. All gingival margins were prepared at the cementum-enamel junction. Teeth were filled by use of a multi-incremental technique, finished with discs, and immediately immersed in 2% erythrosin B for 12 h at 37 degrees C. Three transverse sections were made at 0.5 mm, 2 mm, and 3.5 mm over the cementum-enamel margin and evaluated under a stereomicroscope. Microleakage was scored linearly along the dentin/enamel-restoration interface. Sections at the cementum-enamel level showed significantly higher microleakage than the other two. Significant differences were observed between the various combinations of materials. Early marginal microleakage in Class II restorations depends not only on filling technique and on dentin bonding systems but also on the resin composite. Glass-ionomer cements significantly reduce early marginal microleakage in Class II restorations.     

Microleakage in MOD resin composite with three dentin bonding agents

The extent of microleakage under MOD composites was studied when an aluminum oxalate dentin bonding agent (Tenure), a phosphonated resin bonding agent (Bondlite), and a glass-ionomer cement (Ketac Silver) were used. Three groups of 10 extracted molars were prepared with MOD cavities; one box ended on enamel, the other on cementum. In Group 1, Bondlite was applied to dentin and etched enamel before the sample was restored with a light-cured hybrid composite. In Group 2, a 2-mm increment of Ketac Silver was placed in each box before Bondlite and composite. In Group 3, Tenure was applied to dentin before being restored. Teeth were thermal-cycled, stained in silver nitrate, sectioned, and scored for microleakage. Microleakage along the gingival floor was significantly less at enamel margins than at cementum margins in all three groups. All groups showed severe marginal microleakage on cementum.     

Thickness and morphology of resin-infiltrated dentin layer in young, old, and sclerotic dentin.

The purpose of the present study was to evaluate the morphology of the resin tags and the resin-infiltrated dentin layer (RIDL) of several bonding systems in superficial vs deep young, old, and sclerotic human dentin. Dentin was obtained after the removal of occlusal enamel from extracted molars. Phosphoric acid gels (35-37%) were used to etch dentin before the application of bonding systems (OptiBond FL; Prime & Bond 2.0; Scotchbond Multi-Purpose Plus and Scotchbond 1; One Step). Each bonded specimen was then sectioned into two halves. One half was polished using a standard procedure to evaluate RIDL thickness and morphology by SEM. The other half was demineralized and deproteinized to evaluate the presence and the morphology of resin tags. RIDL was thinner in superficial dentin than in deeper dentin for all the materials tested regardless of the type of dentin. Sclerotic and old dentin showed thinner RIDL, with short resin tags, and fewer lateral branches than normal dentin.     

冷热循环对自粘接树脂水门汀边缘适合性的影响

目的：对自粘接树脂水门汀（RelyX Unicem）与传统树脂水门汀系统（Panavia F,Variolink Ⅱ,Vtique）粘接嵌体边缘适合性进行对比研究。方法：48个新鲜拔除的第一磨牙分为4组,每组12个,分别选用d种树脂水门汀系统粘接嵌体,每组试件选取4个分别冷热循环0次,5000次,10000次后,放置于0．5％的品红溶液中染色24h,顺着嵌体长轴纵剖后在体视显微镜下观察微渗漏情况。结果：4种树脂水门汀系统在不同的冷热循环次数沿着粘接界面表现出低的微渗漏,4种树脂水门汀系统粘接嵌体无明显统计学差异义。结论：自粘接树脂水门汀具有与传统树脂水门汀相似的良好的边缘适合性。     

Er,Cr:YSGG激光和酸蚀处理牙本质表面后的扫描电镜观察

目的 本文通过电镜观察，研究不同预备方法处理牙本质后表面形态的改变及树脂-牙本质界面形态的差别。方法 用10颗拔除的第三磨牙制作牙本质片，每个牙本质片预备三个窝洞，分别用传统方法加酸蚀预备，Er，Cr：YSGG激光预备及激光加酸蚀预备。将10个牙本质片分为A、B两组，A组在电镜下观察牙本质表面形态改变；B组用流动树脂充填，暴露树脂-牙本质界面，样本经处理后在电镜下观察比较。结果 A组：传统方法预备后牙本质表面可见开放的牙本质小管口；激光预备后开放的牙本质小管口呈现火山口样；激光加酸蚀处理后的牙本质小管周围呈现白晕。B组：传统预备方法的树脂一牙本质界面可见混合层，圆锥型树脂突和侧枝连接的形成；单纯激光预备后界面没有混合层的形成，形成的树脂突呈圆柱型，较长并且细密；激光加酸蚀处理后界面可见少量混合层形成，树脂突圆柱型，粗、长且有少量侧枝连接。结论 Er，Cr：YSGG激光加酸蚀处理后，开放的牙本质小管周围可见来完全脱矿的管周牙本质．树脂一牙本质界面可见混合层和粗长的圆柱形树脂突。     

Nd:YAG激光对不同水门汀与牙本质间边缘微渗漏的影响

目的:评价Nd:YAG激光对不同水门汀与牙本质之间边缘微渗漏的影响。方法:选用人离体磨牙48颗,间接法制作树脂嵌体,随机分为激光组和对照组,激光组使用80 mJ、10 Hz脉冲Nd:YAG激光照射后,分别用6种水门汀粘结树脂嵌体。全部试件放在37℃生理盐水中7 d,并冷热循环300次后,放置于0.5%的品红溶液中染色24 h,沿嵌体长轴纵剖后在根管显微镜下观察微渗漏情况,采用SPSS 17.0软件包对数据进行统计学处理。结果:6组牙本质经Nd:YAG激光照射后微渗漏程度均有降低趋势,且前2种水门汀有统计学差异(P<0.05)。另外,树脂水门汀与牙本质之间的微渗漏程度比水基水门汀低。结论:80 mJ、10 Hz脉冲Nd:YAG激光照射牙本质壁,可提高洞壁的密合度,减少微渗漏。     

Er：YAG激光备洞与树脂充填微渗漏的实验研究

目的：评价Er：YAG激光备洞对树脂充填材料边缘微渗漏的影响。方法：选择48颗年轻前磨牙随机分成4组,每组12颗牙,用Er：YAG激光或高速牙钻制备ⅴ类洞。对照组：牙钻备洞＋35%磷酸酸蚀;实验1组：激光备洞＋35%磷酸酸蚀;实验2组：激光备洞＋自酸蚀粘接;实验3组：单纯激光备洞。树脂充填,经冷热循环试验后染色24h,体视显微镜下观察微渗漏,统计学处理数据。结果：龈壁的染料渗透,4组间无统计学差异;壁的染料渗透,以实验3组较明显,与对照组、实验1、2组有统计学差异（P〈0.05）;各组内壁的染料渗透均比龈壁轻,但没有统计学差异。结论：Er：YAG激光备洞,35%磷酸酸蚀或自酸蚀粘接处理可减少洞壁与树脂充填边缘的微渗漏。     

Microleakage in class V gingiva-shaded composite resin restorations

The purpose of this study was to evaluate the microleakage in Class V cavities restored with a new gingiva-shaded microhybrid composite resin and with a conventional microhybrid composite resin using three different dentin bonding systems (DBS). Class V cavities were prepared in sixty freshly extracted human teeth with the incisal margin in enamel and the apical margin in dentin/cementum. Restored specimens, after thermocycling, were placed in 2% methylene blue solution for 24 hours. Longitudinal sections were obtained and studied with a stereomicroscope for assessment of the microleakage according to degree of dye penetration (scale 0-3). Data were analyzed with Kruskal-Wallis test and with Mann-Whitney U-test.IN THIS STUDY THERE WAS NO LEAKAGE IN ENAMEL: all the cavities showed no dye penetration at the incisal margins (located in enamel). None of the DBS used eliminated microleakage in apical margins (located in dentin or cementum): three-step total-etch and single-step self-etch were more effective in reducing microleakage in dentin margins when compared with two-step total-etch. This in vitro study concluded that microleakage in Class V cavities restored with the composite resins tested is similar.