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91.
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. 相似文献92.
Background: Previous studies investigated the efficacy and applicability of tissue adhesives in gastrointestinal surgery while no evidence is available to date about a novel compound, TachoSil (Takeda, Zurich, Switzerland). The primary aim of this observational study was to assess the effect of new fibrin sealant on the incidence of postoperative complications in a homogeneous group of patients submitted to upper gastrointestinal surgery for cancer. Methods: Two cohorts of 28 and 34 patients undergoing upper gastrointestinal for surgery were compared. In the first cohort, the anastomotic site was treated with TachoSil fibrinogen-thrombin-collagen patches and in the second no collagen sponge or any other hemostatic sealant was used. Postoperative complications and outcomes as well as postoperative biochemical parameters were analyzed. Results: Postoperative complications occurred in 12 patients (35.3%) and 2 patients (7.1%) in control and collagen sponge group respectively (χ2 = 3.539, p < 0.05), with no anastomotic leakage in the collagen sponge group. A binary logistic regression analysis showed that the nonuse of collagen sponge [odds ratio (OR) = 0.025, 95% confidence interval (CI) = 0.001–0.457, p = 0.01] was independently associated with postoperative complication occurrence. Conclusions: The addition of fibrinogen-thrombin-collagen sponge patch may reduce postoperative complication rate after upper gastrointestinal surgery for cancer. Further study to delineate the role of TachoSil in gastrointestinal surgery are also needed to demonstrate improved effectiveness and applicability. 相似文献
93.
94.
Methods:A total of 62 patients were enrolled. The OT group underwent laparoscopy (n = 16), and the CT group (n = 46) did not. We compared early and late outcomes between the 2 groups.Results:Times to first flatus, oral intake, and defecation after treatment were shorter in the OT group (P = .030, .033, and .024), and the recurrence rate was lower in the OT group than in the CT group (6.2% vs 32.6%; P = .038). Time from discharge to first recurrence was longer in the OT group than in the CT group (172 vs 104.6 ± 26.5 days, P = .027).Conclusions:SBO related to a single adhesive band is not effectively treated by CT. However, laparoscopic OT provides notable success if the surgery is performed early. Therefore, it should be the preferred treatment. 相似文献
95.
目的:制备地塞米松磷酸钠口服液并初步考察其抗大鼠粘连性肠梗阻作用。方法:采用高效液相色谱(HPLC)法测定地塞米松磷酸钠的含量、油水分配系数、考察地塞米松磷酸钠稳定性影响因素;采用裘法祖造模法和试剂盒考察其抗大鼠粘连性肠梗阻的作用。结果:在pH 1.0~8.0范围内,地塞米松磷酸钠的油水分配系数均小于零;pH为8.0时药物降解最慢,抗氧剂Na2SO3和稳定剂丙二醇联用可增加地塞米松磷酸钠的稳定性。与尾静脉注射给药相比,地塞米松磷酸钠口服液能显著降低粘连性肠梗阻(AIO)大鼠肠道丙二醛(MDA)含量(P<0.05),显著提高超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-PX)的活性(P<0.01,P<0.01)。结论:地塞米松磷酸钠口服液具有抗大鼠粘连性肠梗阻作用且其作用强于注射液。 相似文献
96.
Korasli D Ziraman F Ozyurt P Cehreli SB 《Journal of the American Dental Association (1939)》2007,138(5):634-640
BACKGROUND: The authors evaluated the coronal marginal leakage of endodontically treated teeth bonded with four self-etching adhesives and one total-etch adhesive system. MATERIALS AND METHODS: The investigators prepared Class II cavities in 60 extracted human premolars. They performed conventional endodontic therapy using a resin-based sealer and gutta-percha points. They randomly assigned each tooth to a group receiving one of the following adhesives: Adper Prompt L-Pop (3M ESPE, Seefeld, Germany), Clearfil SE Bond (Kuraray, Osaka, Japan), FL Bond (Shofu, Kyoto, Japan), Single Bond (3M ESPE) or Xeno III (Dentsply De Trey, Konstanz, Germany). They restored all teeth with resin-based composite material (Z250, 3M ESPE). Specimens underwent thermocycling and dye penetration and were sectioned longitudinally. The authors photographed the sections under a stereomicroscope. They transferred the images to an IBM-compatible personal computer for quantitative assessment of dye penetration using image analysis software. They analyzed data by means of Kruskal-Wallis and Mann-Whitney U tests (P = .05) and evaluated two specimens from each group under scanning electron microscopy. RESULTS: None of the tested self-etch adhesives completely eliminated microleakage. Dye leakage was restricted to the coronal cavity walls; it did not migrate toward the pulp chamber or toward the root canal. Single Bond and Clearfil SE Bond showed significantly lower dye penetration values at occlusal and gingival margins. CONCLUSIONS: The coronal sealing performance of the tested self-etch adhesive systems in endodontically treated teeth was material-dependent. The use of Clearfil SE Bond in such teeth can help achieve a marginal seal comparable to that achieved with Single Bond. 相似文献
97.
PURPOSE: The purpose of this study was to evaluate the efficacy of three desensitizing agents vs. placebo. MATERIALS AND METHODS: One hundred and six hypersensitive teeth of 26 patients were included in this study, and the baseline hypersensitivity level of all teeth was established as 'moderate' by using Visual Analogue Scale (VAS). The teeth were divided into four groups: to the first group 5% potassium nitrate bio-adhesive gel, to the second 2% sodium fluoride bio-adhesive gel and to the third one step adhesive system Prompt L-Pop were applied as desensitizing agents. Group 4 was the control group in which a desensitizer-free bio-adhesive gel was used as placebo. Post treatment and eighth week control measurements were recorded on VAS. RESULTS: It was observed that the efficacy of three desensitizing agents did not differ from each other (P >0.05) and except for placebo all reduced moderate dentin hypersensitivity effectively (P <0.05). Clinical relevance: Five per cent potassium nitrate, 2% sodium fluoride bio-adhesive gels and one-step bonding agent Prompt L-Pop were effective in reducing moderate dentine hypersensitivity. 相似文献
98.
目的:探讨Dermabond皮肤粘合剂对外科手术切口的愈合效果,为临床外科手术切口愈合提供参考。方法:选取2017年8月-2018年8月接诊的外科手术患者80例。按自愿原则照随机数表法分为观察组(46例)与对照组(34例)。对照组患者手术切口采用传统缝线缝合,观察组患者手术切口采用Dermabond皮肤粘合剂缝合。比较两组术后基本情况、切口愈合效果及切口美观满意度。结果:观察组切口闭合时间、术后8d切口护理费用明显少于对照组,观察组皮肤红肿、术后3d伤口疼痛、瘢痕形成发生率均明显低于对照组,差异有统计学意义(P<0.05)。观察组愈合质量明显优于对照组,切口美观满意度明显高于对照组,差异有统计学意义(P<0.05)。结论:Dermabond皮肤粘合剂用于外科手术切口闭合效果良好,能有效缩短切口闭合时间,降低并发症及瘢痕形成发生率,值得广泛应用。 相似文献
99.
目的探讨肠梗阻病人行经鼻肠梗阻导管置入术中应用盐酸奥布卡因凝胶的价值。方法将60例拟行经鼻肠梗阻导管置入术的肠梗阻病人按随机数字量表法分为研究组和对照组,每组各30例,研究组病人术前应用盐酸奥布卡因凝胶10 ml(30 mg)进行鼻腔麻醉及导管前端润滑,对照组病人术前于鼻腔及导管前端涂抹石蜡油进行润滑,比较两组病人的一次性置管成功率、置管时间及术后并发症发生率,并采用视觉模拟评分法(visual analogue scale,VAS)进行评分。结果研究组病人的一次性置管成功率为96.7%(29/30),对照组病人的一次性置管成功率为70.0%(21/30),差异有统计学意义(P<0.05)。与对照组比较,研究组病人置管所用时间明显减少,术中疼痛VAS评分降低,差异均有统计学意义(均P<0.05)。两组病人均未出现穿孔、出血等并发症。结论盐酸奥布卡因凝胶在肠梗阻病人行经鼻肠梗阻导管置入术中应用,提高了一次性置管成功率,减少置管所用时间,明显地减轻了病人术中的疼痛不适,未见并发症,效果满意。 相似文献
100.
Cheryl T. Lee Sam S. Chang Ashish M. Kamat Gilad Amiel Timothy L. Beard Amr Fergany R. Jeffrey Karnes Andrea Kurz Venu Menon Wade J. Sexton Joel W. Slaton Robert S. Svatek Shandra S. Wilson Lee Techner Richard Bihrle Gary D. Steinberg Michael Koch 《European urology》2014