表面处理对双固化黏结剂Panavia F黏接强度的影响

目的评价表面处理对双固化黏结剂Panavia F与不同界面黏接强度的影响。方法测定Panavia F与牙本质使用和不使用牙本质处理剂ED primer时的剪切强度,以及Panavia F与钴铬合金、镍铬合金、纯钛、银金钯合金使用和不使用金属表面处理剂Alloy primer时的剪切强度,数据作统计学检验,分析其黏接机制。结果使用ED primer处理后,Panavia F与牙本质的剪切强度从9.1MPa提高到17.6MPa;使用Alloy primer处理后,Panavia F与纯钛的剪切强度从29.0MPa提高到35.9MPa,而与处理后的银金钯合金的剪切强度从21.6MPa提高到30.2MPa。结论Panavia F通过采用ED primer对牙本质的表面处理显著提高对牙本质的黏结强度;Alloy primer可以显著提高纯钛和贵金属与黏结剂的黏结强度,而对钴铬合金和镍铬合金则不明显。     

不同蚀刻处理时间对CERINATE瓷与树脂剪切粘结强度的影响

目的：评价不同蚀刻处理时间对Ｃｅｒｉｎａｔｅ瓷与树脂剪切粘结强度的影响。方法：瓷试件用陶瓷酸蚀剂分别处理０～２１０ｓ,然后与树脂粘结测试剪切粘结强度。结果：蚀刻处理可明显提高瓷与树脂的粘结强度。未经酸蚀处理的瓷试件几乎不与树脂发生粘结。不同处理时间瓷与树脂粘结强度有区别,尤以蚀刻１５０ｓ获得的强度最高。结论：酸蚀处理可使瓷—树脂得高的粘结强度,酸蚀时间对粘结强度有影响。     

Analysis of pre-test failures and bond-strengths of seven adhesive systems to bovine dentine: A nine-year novice/beginner operator study

Objective

The aims were to evaluate, via multi-year student cohorts: (i) the incidence of pre-test failures and (ii) shear bond strengths of single- and multi-step adhesives to bovine dentin.

烤瓷冠桥崩瓷后专用树脂修补的研究

目的 探讨专用树脂修补烤瓷冠桥崩瓷的临床适用范围和优缺点，并通过实验为临床研究提供依据。方法对35例崩瓷患牙在临床上用专用树脂进行修补，观察疗效二年；采用抗剪切实验测定并比较专用树脂与不同处理方法的烤瓷及镍铬合金界面的粘接强度，并与光敏树脂与离体牙釉质粘结强度比较。结果专用树脂修补崩瓷成功率达到80％；试验显示专用树脂与瓷粘接强度可达到普通光敏树脂与新鲜离体牙釉质粘接强度的93％左右，二者统计学上无显著性差异。不同界面（烤瓷面与金属面P〈0．01）以及界面不同处理方法（酸蚀与酸蚀加喷砂P〈0．05）对各实验组剪切强度有不同程度影响，差异有显著性，与临床观察结果相符。结论若适应证选择合适并对崩瓷面进行必要处理，专用树脂修补烤瓷冠桥崩瓷是一种省时、省力、经济的有效方法。     

Shear bond strength of one-step self-etch adhesives with different co-solvent ingredients to dry or moist dentin

Objective

To evaluate the shear bond strength of one-step self-etch adhesives with different co-solvent ingredients to dry or moist dentin.

Materials and methods

A total of 60 extracted teeth were used in this study, and were divided according to the adhesive systems and dentin conditions into 6 groups of 10 teeth each [Xeno III – dry dentin, Xeno III – moist dentin, Adper Prompot L-Pop – dry dentin, Adper Prompot L-Pop – moist dentin, iBond – dry dentin, and iBond – moist dentin]. Resin composite cylinder was built up on each specimen, and then thermocycled. A shear load was applied to the specimens using universal testing (Instron machine) at a cross-head speed of 0.5 mm/min until failure occurred. Data were statistically analyzed by one-way ANOVA and Bonferroni multiple comparison test at 95% confidence level.

Results and conclusion

Based on the findings of this study: The highest mean shear bond strength to dry dentin was seen when Xeno III containing ethanol co-solvent ingredient was used. The highest mean shear bond strength to moist dentin was seen when iBond which contains acetone co-solvent ingredient was used. In the absence of a co-solvent ingredient in self-etch adhesive (Adper Prompot L-Pop), the mean shear bond strengths to dry and moist dentin were low with no significant difference between them.     

Ethanol-wet bonding may improve root dentine bonding performance of hydrophobic adhesive

Objectives

The current study aimed to assess ethanol-wet dentine surfaces by atomic force microscopy (AFM), and to evaluate the efficacy of ethanol-wet bonding on root dentine by determining the shear bond strength (SBS) and interfacial nanoleakage expression.

Methods

Flat dentine slices from human premolar roots were randomly grouped into five. All specimens were acid-etched, rinsed, and left moist. They were then treated with 100% ethanol for 0 s (control group), 20 s (Group 1), 60 s (Group 2), three 60 s periods (Group 3), or stepwise ethanol application (Group 4). After treatment, each group was bonded either with Adper™ Scotchbond™ Multi-Purpose (Scotchbond) or experimental hydrophobic adhesive. Nano-scale adhesion forces (Fad) were probed by AFM and analysed using one-way ANOVA. The SBS results were analysed using two-way ANOVA. Tukey's test was employed for multiple comparisons.

Results

Ethanol-wet protocols significantly decreased the value of Fad (p < 0.001). When bonded with Scotchbond, ethanol treatment did not affect the bond strength (p > 0.05), but decreased the interfacial nanoleakage. The SBS values of the groups bonded with hydrophobic adhesive varied with different ethanol-wet protocols (p < 0.05). Decreased nanoleakage was manifested in all experimental groups, except Group 1. Compared with the classical water-wet bonding with Scotchbond in the control group, Group 4 bonded with hydrophobic adhesive exhibited a significantly higher bond strength (p < 0.05).

Conclusions

Ethanol-wet bonding using a stepwise ethanol application protocol may have potential benefits in the root dentine bonding of hydrophobic adhesive.     

The role of learning and coordination in strength training

Summary The central changes associated with a period of strength training have been investigated in a group of 32 young healthy volunteers. Subjects participated in one of three 12 week training programmes, which required different degrees of skill and coordination. Study 1 consisted of unilateral isometric training of the quadriceps with the contralateral leg acting as a control, the apparatus providing firm back support and a lap strap. In Study 2 training consisted of unilateral concentric leg-extension with back support and hand-grips. In Study 3 subjects performed bilateral leg-extension with no back support. Measurements of maximum voluntary isometric strength were made at 2–3 week intervals and a continual record was kept of the weights lifted in Studies 2 and 3. The largest increase in isometric force was seen for the trained leg in Study 1 (approximately 40%). There was no significant change in strength in the contralateral untrained leg. In Studies 2 and 3 there was a large increase in training weights (about 200%) associated with smaller increase in isometric force (15–20%). It is concluded that a large part of the improvement in the ability to lift weights was due to an increased ability to coordinate other muscle groups involved in the movement such as those used to stabilise the body. The importance of these findings for athletic training and rehabilitation is discussed.     

A novel technique of detecting MRI‐negative lesion in focal symptomatic epilepsy: Intraoperative ShearWave Elastography

Focal symptomatic epilepsy is the most common form of epilepsy that can often be cured with surgery. A small proportion of patients with focal symptomatic epilepsy do not have identifiable lesions on magnetic resonance imaging (MRI). The most common pathology in this group is type II focal cortical dysplasia (FCD), which is a subtype of malformative brain lesion associated with medication‐resistant epilepsy. We present a patient with MRI‐negative focal symptomatic epilepsy who underwent invasive electrode recordings. At the time of surgery, a novel ultrasound‐based technique called ShearWave Elastography (SWE) was performed. A 0.5 cc lesion was demonstrated on SWE but was absent on B‐mode ultrasound and 3‐T MRI. Electroencephalography (EEG), positron emission tomography (PET), and magnetoencephalography (MEG) scans demonstrated an abnormality in the right frontal region. On the basis of this finding, a depth electrode was implanted into the lesion. Surgical resection and histology confirmed the lesion to be type IIb FCD. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here .     

上肢康复操在维持性血液透析患者中的应用研究

目的 评价上肢康复操在维持性血液透析患者中的应用效果。 方法 选取2021年10月—12月于山东省某三级甲等医院血液净化中心行维持性血液透析治疗的患者77例,按随机数字表分为试验组38例和对照组39例,试验组在常规护理的基础上进行上肢康复操训练,对照组只接受常规护理。分别比较干预前和干预3个月后两组的双手握力、肩关节活动度、动静脉内瘘血流量及非内瘘侧头静脉直径。 结果 试验组36例、对照组38例完成研究。干预前两组双手握力、肩关节活动度、动静脉内瘘血流量及非内瘘侧头静脉直径比较,差异无统计学意义（P>0.05）;干预后试验组与对照组比较,内瘘侧握力（t=-2.350,P=0.022）、非内瘘侧握力（t=-3.693,P<0.001）,内瘘侧肩关节外展（t=-2.468,P=0.016）、外旋（t=-5.167,P<0.001）、内旋（t=-2.059,P=0.043）,动静脉内瘘血流量（t=-2.020,P=0.047）、非内瘘侧头静脉直径（t=-5.229,P<0.001）均增加,差异具有统计学意义。 结论 上肢康复操训练有助于改善维持性血液透析患者的上肢功能及维护动静脉内瘘。     

Cellular Fluid Mechanics and Mechanotransduction

Mechanotransduction, the transformation of an applied mechanical force into a cellular biomolecular response, is briefly reviewed focusing on fluid shear stress and endothelial cells. Particular emphasis is placed on recent studies of the surface proteoglycan layer (glycocalyx) as a primary sensor of fluid shear stress that can transmit force to apical structures such as the plasma membrane or the actin cortical web where transduction can take place or to more remote regions of the cell such as intercellular junctions and basal adhesion plaques where transduction can also occur. All of these possibilities are reviewed from an integrated perspective.