氯已定预处理对两步法自酸蚀粘接剂牙本质粘接界面稳定性的影响

目的：探讨氯已定预处理对两步法自酸蚀粘接剂的牙本质粘接界面稳定性的影响.方法：40颗离体人磨牙沿垂直于牙长轴的方向切割,暴露冠中部牙本质作为粘接面,牙本质试件随机分为两组,一组在粘接处理前涂布0.2％氯已定为实验组,一组无预处理为对照组,两组经两步法自酸蚀粘接剂SE Bond处理后,堆积复合树脂制备成粘接试件.每组随机抽取2个试件借助微拉曼光谱仪分析粘接剂的双键转化率,剩余的18个试件随机分为两个亚组,分别于即刻和冷热循环5000次后检测微拉伸粘接强度和界面的纳米渗漏情况.结果：0.2％氯已定预处理对SE Bond的树脂双键转化率无显著性影响（P＞0.05）.即刻测试时,对照组和实验组间的微拉伸粘接强度和纳米渗漏差异无统计学意义（PP ＞0.05）.冷热循环老化处理后,实验组的微拉伸粘接强度显著高于对照组,纳米渗漏程度显著低于对照组（P＜0.05）.结论：0.2％氯已定预处理不会干扰SE Bond的树脂聚合,且可提高其与牙本质粘接界面的稳定性.     

单瓶型通用粘接剂在牙本质粘接中的应用评价

［摘要］ 目的 评价2种单瓶型通用粘接剂在自酸蚀模式下应用与牙本质的粘接强度以及纳米渗漏情况。方法 制作40枚牙本质样本,分别使用Singlebond Universal和All-Bond Universal 2种单瓶型通用粘接剂在自酸蚀模式下处理牙本质表面,与复合树脂粘接制作粘接试件。各组粘接试件一半于24 h水储后（未老化）切割成细条,测试微拉伸粘接强度,另一半经受10 000次冷热循环后（老化）测试微拉伸粘接强度。数据以单因素方差分析和Tukey多重比较进行检验分析。各组代表性试件处理后以扫描电镜观察粘接界面,检测纳米渗漏情况。结果 不论是否经过老化,2种粘接剂组均获得了较高的粘接强度值,但扫描电镜均能发现纳米渗漏存在。结论 两种单瓶型通用粘接剂在自酸蚀模式下应用均能提供较好的粘接性能,但无法避免纳米渗漏的发生。     

不同预处理剂对乳牙牙本质粘接耐久性的影响

目的 探讨不同预处理剂对乳牙牙本质粘接耐久性的影响。方法 选取42颗因滞留而拔除的乳磨牙,其中24颗沿近远中向切开为颊舌侧两部分得到48个样本,用于剪切粘接强度实验;另外18颗用于纳米渗漏实验。两项实验均按照不同预处理方式将样本随机分为3组,A组：蒸馏水预处理组,B组：2%氯己定预处理组,C组：10 mg/mL白藜芦醇预处理组。制备实验试件,分别在即刻和10%次氯酸钠溶液老化1 h后进行剪切粘接强度检测、界面纳米渗漏评估和扫描电子显微镜观察,评价不同预处理剂对粘接界面的影响。结果 即刻测试各组的剪切粘接强度无显著差异。老化后C组的剪切粘接强度显著高于A组和B组（P<0.05）。A组老化后的剪切粘接强度显著低于即刻（P<0.05）,B组和C组在老化前后的剪切粘接强度无显著差异（P>0.05）。C组的界面纳米渗漏程度在老化前后比较无显著差异,老化后C组的纳米渗漏程度最低（P<0.05）。结论 氯己定和白藜芦醇预处理剂均可以改善乳牙牙本质的粘接耐久性,但白藜芦醇的效果优于氯己定。     

季铵盐单体改性粘接剂对牙本质粘接界面耐酶解能力的影响

目的 研究季铵盐单体改性粘接剂对牙本质粘接界面耐酶解性能的影响,探索提高牙本质粘接耐久性的新方法.方法 30颗无龋人第三磨牙通过随机数字表法随机分为3组(每组10颗):季铵盐单体[2-甲基丙烯酰氧乙基-正十二烷基-甲基溴化铵(2-methacryloxylethyl dodecylmethyl ammonium bromide,MAE-DB)]改性的粘接剂(AdperTM Single Bond 2)组(简称MAE-DB组)、氯己定组和阴性对照组(AdperTM Single Bond 2粘接剂).全酸蚀粘接技术制作标准牙本质粘接试件,37℃水浴浸泡24 h后,制成微拉伸试件,浸泡于酶解液中0、24和120 h(每组每个时间点30个试件).检测各组试件粘接强度、断裂模式和纳米渗漏情况.结果 未经酶解处理的各组试件粘接强度差异无统计学意义(P＞0.05).酶解处理24和120 h后,MAE-DB组的粘接强度分别为(31.13 ±8.77)和(24.14±6.64) MPa,分别显著高于阴性对照组相应时间点[(25.63±6.90)和(15.22±6.57) MPa](P＜0.05).酶解处理后阴性对照组的断裂多发生于混合层底部,而氯己定组和MAE-DB组断裂多发生于混合层顶部.酶解处理前各组均可见少量的银离子沉积于混合层底部.酶解处理120 h后,扫描电镜显示,氯己定组和MAE-DB组混合层底部的纳米渗漏银离子比阴性对照组少,纳米渗漏分级计数差异有统计学意义(P＜0.05).结论 MAE-DB改性牙本质粘接剂可有效提高牙本质粘接界面的耐酶解能力.     

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。     

参与不同牙本质粘接界面退变过程中基质金属蛋白酶种类的研究

目的 研究参与两种粘接剂形成的牙本质粘接界面退变过程中基质金属蛋白酶（ MMPs）的种类。方法 制备Single Bond 2和Clearfil S3 Bond微剪切粘接试件,无菌人工唾液中分别浸泡 0、6个月测试粘接强度,场发射扫描电镜（FE-SEM）观察界面断裂模式。制备4 mm×3 mm×1 mm牙本质片,分为对照组、Single Bond 2组和Clearfil S3 Bond组,无菌人工唾液浸泡 0、6个月后,液相芯片技术测定各组 MMP-1、-2、-3、-8、-9含量。结果 老化 6个月后,各组粘接强度显著下降。与对照组相比,老化过程中不同粘接剂组 MMP-1、-3含量无明显变化,Single Bond 2组 MMP-2、-8、-9含量显著降低,Clearfil S3 Bond组MMP-8、-9含量显著降低。结论 老化6个月后两种粘接试件均发生粘接界面退变,牙本质源MMP-2、-8、-9的含量显著降低,提示这些MMPs可能参与了牙本质粘接界面的退变。     

硬化牙本质粘接界面纳米渗漏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纳米微渗漏情况。方法选取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，随机分为3组；选取12颗新鲜拔除的无龋人上颌前磨牙为对照组，人工形成楔状缺损，随机分为3组。选用3种牙本质粘接系统，即Single Bond（SB）、Clearfil SE Bond（CB）、Xeno Ⅲ（XB），按照厂家说明分别应用于牙本质楔状缺损表面。自凝树脂封闭根尖，6组试样分别浸泡于0.1%罗丹明B异硫氰酸盐的50%乙醇溶液中24 h，慢速砂片切割后CLSM下进行观察。结果粘接剂种类、牙本质类型对粘接界面的纳米渗漏长度有显著影响（P<0.05）。无论正常牙本质还是硬化牙本质，SB产生的纳米渗漏长度均大于CB和XB，且差异有统计学意义（P<0.05）。CB、XB之间差异无统计学意义（P>0.05）。正常牙本质上SB产生的纳米渗漏长度与硬化牙本质上SB产生的纳米渗漏长度间差异无统计学意义（P=0.148）；而CB、XB作用于正常牙本质上产生的纳米渗漏长度均大于硬化牙本质，且差异有统计学意义（P<0.05）。结论3种类型粘接系统均有纳米渗漏发生，硬化牙本质的粘接界面下纳米渗漏多发生在树脂与正常牙本质、硬化牙本质三者结合处的树脂与正常牙本质结合界面。     

评价新型粘接剂在不同粘接模式下的牙本质粘接性能

目的评价1种新型单瓶型多模式粘接剂在不同粘接模式下与牙本质的粘接强度和粘接耐久性。方法制作3组牙本质/复合树脂粘接试件,其中每组牙本质在粘接前接受不同的表面调节。包括不处理(空白对照),Singlebond Universal粘接剂自酸蚀模式下调节牙本质,Singlebond Universal粘接剂在酸蚀冲洗模式下调节牙本质。测量各组粘接试件水储24 h和180 d的微拉伸粘接强度值并进行统计分析。以扫描电子显微镜观察各组试件的粘接界面。结果不论老化前还是老化后,3组间的粘接强度均存在显著性差异,其中空白组的粘接强度值最低,另两组间则无显著性差异。人工老化使空白组的粘接强度值显著下降,而对另两组则并无显著影响。结论 Singlebond Universal粘接剂在自酸蚀粘接模式和酸蚀冲洗粘接模式下均能够形成与牙本质良好的粘接。     

牙本质粘接界面微渗漏的二维形态

目的观察牙本质粘接界面微渗漏的二维形态。方法去除磨牙面釉质,暴露牙本质,分别用3种粘接剂（Prime & Bond NT、Contax和Adper Prompt）粘接牙本质,其上制作复合树脂冠。顺牙齿长轴,在相互垂直的两个方向片切牙齿,制备条状试样。每个牙齿制备的试样为两组,一组进行冷热循环10 000次,另一组不冷热循环,之后相继浸泡于氨化硝酸银溶液及显影液中,然后测定微拉伸粘接强度。最后在扫描电镜下观察界面破坏和混合破坏试样的断面。结果粘接界面微渗漏的二维形态呈各种不同的树枝状,从边缘伸向中心,冷热循环后的微渗漏程度明显加重。结论牙本质粘接界面的微渗漏并非是从外到里齐头并进,而是呈树枝状,其程度与粘接剂种类和是否进行冷热循环有关。     

人工唾液浸泡对两种自酸蚀粘接剂粘接界面的影响

目的探讨含细菌的人工唾液对两种自酸蚀粘接剂粘接界面纳米渗漏的影响。方法选用自酸蚀粘接剂Adper Prompt（AP）和Contax分别与正常牙本质粘接并制备微拉伸试件,之后将试件浸泡于含细菌的人工唾液中,分别在即刻、1周、1月、3月时取出进行硝酸银染色,用扫描电镜（SEM）观察粘接界面银沉积情况,并用NlH图像分析软件量化处理,以界面银沉积面积占断裂界面的百分比来评价界面纳米渗漏程度。结果粘接界面在即刻、1周、1月、3月时的银沉积面积百分比分别为AP：（17.00±5.40）%、（18.71±6.94）%、（22.81±5.60）%、（26.79±5.77）%;Contax：（11.90±5.17）%、（12.41±4.42）%、（14.73±3.46）%、（17.64±5.39）%。结论无论浸泡人工唾液与否,粘接试件都无法避免纳米渗漏的产生;含细菌的人工唾液浸泡会影响粘接的稳定性,其中以AP组的稳定性较差,浸泡三个月即表现出界面银渗漏程度的显著增加。     

Effects of dentin characteristics on interfacial nanoleakage

Water emanating from dentinal tubules during air-drying and light-curing of adhesives leads to entrapment of droplets at the resin-dentin interface and contributes to nanoleakage. This study tested the null hypothesis that characteristics of substrate dentin and type of adhesive used for bonding would not affect the occurrence of nanoleakage. Three self-etch adhesives were used to bond to 4 types of dentin with different characteristics in 12 groups. After silver challenge, nanoleakage percentage was measured within the hybrid layer of each sample. The deep dentin cut perpendicular to tubules always showed a significantly higher nanoleakage percentage compared with that of the other 3 types of dentin. The percentages of nanoleakage within the hybrid layers were not statistically different among adhesives. However, when bonding to deep perpendicular dentin, both all-in-one adhesives revealed more distinct nanoleakage within the adhesive layer compared with that achieved with Clearfil SE Bond, a two-step self-etch adhesive. The results did not support the null hypothesis.     

Bioactive effects of a calcium/sodium phosphosilicate on the resin-dentine interface: a microtensile bond strength, scanning electron microscopy, and confocal microscopy study

This study evaluated, through microtensile bond strength (μTBS) testing, the bioactive effects of a calcium/sodium phosphosilicate (BAG) at the resin-dentine interface after 6 months of storage in phosphate buffer solution (PBS). Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) were also performed. Three bonding protocols were evaluated: (i) RES-Ctr (no use of BAG), (ii) BAG containing adhesive (BAG-AD), and (iii) BAG/H (3) PO (4) before adhesive (BAG-PR). The dentin-bonded specimens were prepared for μTBS testing, which was carried out after 24 h or 6 months of storage in PBS. Scanning electron microscopy ultramorphology analysis was performed after debonding. Confocal laser scanning microscopy was used to evaluate the morphological and nanoleakage changes induced by PBS storage. High μTBS values were achieved in all groups after 24 h of storage in PBS. Subsequent to 6 months of storage in PBS the specimens created using the BAG-AD bonding approach still showed no significant reduction in μTBS. Moreover, specimens created using the BAG-AD or the BAG-PR approach showed an evident reduction of nanoleakage after prolonged storage in PBS. The use of BAG-containing adhesive may enhance the durability of the resin-dentine bonds through therapeutic/protective effects associated with mineral deposition within the bonding interface and a possible interference with collagenolytic enzyme activity (matrix metalloproteinases) responsible for the degradation of the hybrid layer.     

氢氟酸酸蚀对两种树脂-陶瓷复合材料黏结强度影响研究

目的    研究氢氟酸酸蚀对两种树脂-陶瓷复合材料黏结强度的影响。方法    选择Hyramic和Vita Enamic两种树脂-陶瓷复合材料,每种材料再按照表面处理方式分为未处理组（Hyramic-NT组和Vita Enamic-NT组）以及氢氟酸酸蚀组（Hyramic-HF组和Vita Enamic-HF组）。测量表面处理后的复合材料表面粗糙度,扫描电镜观察表面形貌。使用Multilink N树脂水门汀将组内的复合材料两两黏结,制作微拉伸试件,37℃去离子水中水浴24 h后进行微拉伸强度测试。将粗糙度及微拉伸黏结强度结果采用SPSS 22.0软件进行两因素析因设计资料的方差分析。结果　不同的表面处理方式对微拉伸黏结强度和粗糙度有影响（均P < 0.05）,材料种类对微拉伸黏结强度和粗糙度无明显影响（均P > 0.05)。Hyramic-HF组微拉伸黏结强度高于Hyramic-NT组,但差异无统计学意义（P > 0.05）。Vita Enamic-HF组微拉伸黏结强度明显高于Vita Enamic-NT组,差异有统计学意义（P < 0.05）。粗糙度及扫描电镜结果显示,氢氟酸处理后复合材料的表面形貌有明显改变。结论    氢氟酸酸蚀可提高树脂-陶瓷复合材料与树脂水门汀之间的黏结强度,Vita Enamic比Hyramic更适合氢氟酸酸蚀处理。     

Formulation of nano-graphene doped with nano silver modified dentin bonding agents with enhanced interfacial stability and antibiofilm properties

ObjectiveThe aim of this study was to synthesize and characterize reduced nano graphene oxide (RGO) and graphene nanoplatelets (GNPs) doped with silver nanoparticles (nAg) and to prepare an experimental dentin adhesive modified with RGO/nAg and GNP/nAg nanofillers for studying various biological and mechanical properties after bonding to tooth dentin.MethodsNanoparticles were characterized for their morphology and chemical structure using electron microscopy and infrared spectroscopy. Experimental dentin adhesive was modified using two weight percentage (0.25% and 0.5%) of RGO/nAg and GNP/nAg to study its degree of conversion (DC), antimicrobial potential, and cytotoxicity. The effect and significance of these modified bonding agents on resin-dentin bonded interface were investigated by evaluating interfacial nanoleakage, micropermeability, nanodynamic mechanical analysis, micro-tensile bond strength (µTBS), and four-point bending strength (BS),ResultsBoth 0.25% and 0.5% GNP/nAg graphene-modified adhesives showed comparable DC values to the commercial and experimental adhesive (range: 42–46%). The bacterial viability of the groups 0.25% and 0.5% GNP-Ag remained very low under 25% compared to RGO/nAg groups with low cytotoxicity profiles (cell viability>85%). Resin-bonded dentin interface created with GNP/nAg showed homogenous, well-defined hybrid layer and regularly formed long resin tags devoid of any microporosity as evidenced by SEM and confocal microscopy. The lowest nanoleakage and highest bending strength and µTBS was recorded for 0.25% GNP/nAg after 12 months of ageing. A significantly increased nanoelasticity was seen for all experimental groups except for control groups.SignificanceThe addition of 0.25% GNP/nAg showed optimized anti-biofilm properties without affecting the standard adhesion characteristics.     

树脂与无机改性牙本质的粘结界面及其微漏研究

目的：比较不同牙本质表面处理后树脂一牙本质界面的超微结构和微漏程度。方法：于8颗人离体磨牙颊、舌面牙颈部制备箱型V类洞，根据牙本质表面处理方法随机分为磷酸酸蚀组和无机改性组（n=8）。分别涂布粘结剂，复合树脂充填。染料渗入法检测充填体边缘的微漏程度，并观察粘结界面的微观形貌。结果：不同粘结处理方法对微渗漏程度无显著影响（P〉0．05），各组根方渗漏程度显著高于冠方（p〈0．05）；无机改性处理后界面可见混合层形成，树脂突可见大量侧枝伸出。结论：无机改性对牙本质粘结的边缘微漏无显著影响；微机械嵌合作用是无机改性牙本质粘结的重要机制。     

疏水涂层对自酸蚀粘接界面纳米渗漏的影响

目的 研究疏水涂层对自酸蚀粘接剂牙本质粘接界面纳米渗漏的影响.方法 选择新近拔除的32颗无龋人第三磨牙,去除(牙合)面釉质暴露牙本质层,随机分为4组,每组设实验组和对照组.对照组分别用Adper Prompt(AP)、iBond(IB)、Xeno III(XE) 和SE Bond(SE)按使用说明常规粘接,Protect liner F树脂修复;实验组于常规粘接后涂布疏水涂层,Protect liner F树脂修复.垂直于粘接界面切割出4个0.9mm×4mm的试件,经显影固定脱矿后,切成超薄切片,经铀、铅染色后于透射电镜下观察银离子的渗入情况.NIH图像分析软件量化比较纳米渗漏值,统计分析.结果 4种粘接剂纳米渗漏值AP>IB>XE>SE,SE组纳米渗漏较小,与其他3组间差异有统计学意义(P<0.05).疏水涂层运用后与粘接层紧密结合,粘接层明显增厚,纳米渗漏减少,与对照组的差异有统计学意义(P<0.05).结论 疏水涂层有助于形成厚而均一的粘接层,减少自酸蚀粘接界面纳米渗漏的产生.     

Effect of nano-carbonate apatite to prevent re-stain after dental bleaching in vitro

Objectives

This study examined the effect of nano-carbonate apatite (n-CAP) to prevent re-staining and the change of enamel surface after dental bleaching in vitro.

Methods

Twenty-four bovine specimens were bleached for 2 weeks with 10% carbamide peroxide (CP). After bleaching, the specimens were divided into the following four groups: distilled and deionized water (DDW, negative control), 10% n-CAP, NaF (positive control) and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP, positive control). Each group was subjected to pH cycling for 7 days. The specimens were treated for 4 min 3 times per day and re-staining was induced naturally by artificial saliva in the remineralization process. After pH cycling, the changes in colour were evaluated with spectrophotometry and scanning electron microscopy (SEM). The difference in colour between before and after pH cycling was evaluated using an ANOVA and Tukey test.

Results

After pH cycling, the colour difference of n-CAP group was significantly lower than that of the DDW and CPP-ACP groups (p < 0.05). SEM showed that n-CAP particles were deposited regularly on the damaged surface compared to the other groups.

Conclusion

10% n-CAP could significantly maintain the initial colour and protect the damaged enamel structure after bleaching.     

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.