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排序方式: 共有737条查询结果,搜索用时 15 毫秒
1.
《Saudi Dental Journal》2022,34(8):779-787
This study aimed at comparing shear-bond strength (SBS) of different self-etching adhesive systems (Clearfil S3 Bond Plus, G-Premio BOND and IBond) to dentin without or with diode-laser irradiation before photo-polymerization and to determine the effect of storage and thermo-cycling on SBS of adhesive systems. Methods: The buccal surface of 84 extracted maxillary premolars was grounded to create flat surface. The specimens were allocated into 3 groups (n = 28) depending upon the adhesive systems, then each group was divided into two sub-group (I, II) (n = 14). After the placement of respective adhesive systems on the flat surface, adhesive system in group I was photo-polymerized immediately, while in group II, the adhesive systems were exposed to diode-laser before photo-polymerization. Composite cylinder (4 mm in diameter and 2 mm height) was built on the flat surface of each specimen. Then group I and II were divided into two sub-groups (n = 7) according to the storage time and thermo-cycling (1 day without thermo-cycling or 72 days with thermo-cycling) then all the specimens were stored in distilled water. The SBS was measured at the end of storage period. ANOVA, Duncan’s Multiple Range Test and independent t-test “P ≤ 0.05” were used for data analysis. Results: G-premio BOND showed the highest mean value of SBS followed by Clearfil S3 Bond plus without significant difference between them, while IBond revealed the least mean value. Laser irradiation had positive effect on the bond-strength of all tested adhesive systems. The results also showed that the storage with thermo-cycling had negative effect on the bond-strength in groups without laser irradiation for all tested adhesive systems, while for groups with laser irradiation, the reduction in the bond-strength of all tested adhesive systems was not significant. Conclusion: Diode-laser application prior to photo-polymerization of self-etch adhesive systems significantly increased the bond-strength to dentin and can increase the durability of composite adhesion.  相似文献   
2.
冻结肩是常见的肩部疾病,传统非可视化治疗冻结肩效果欠佳。近年来,超声引导具有动态实时定位、无辐射、便携性、低成本等优点在辅助诊断和治疗冻结肩患者中得到成功应用,不仅能提供精确的诊断,也提高了患者中长期的疗效。本文就超声引导辅助诊断和治疗冻结肩的研究进展进行综述。  相似文献   
3.
《Dental materials》2022,38(8):1376-1384
ObjectivesWhen consumed in excess, acidic foods and beverages can cause dental erosions leading to irreversible loss of tooth substance. In many cases, prosthetic rehabilitation of the damaged teeth is mandatory. The aim of this in vitro study was to investigate, for the first time on this scale, the resistance of various commonly used self-adhesive resin luting cements (Bifix SE, VOCO; G-Cem LinkAce, GC; RelyX Unicem, 3 M Oral Care; SpeedCEM Plus, Ivoclar ) against acidic media, and to find out whether they can withstand long-term exposure. These results were compared with an adhesive resin luting cement (Panavia V5, Kuraray) that functioned as reference gold standard. Furthermore we applied area roughness parameters for surface texture analysis in the present investigation, to highlight their advantages for investigations on the surface quality of resin luting cements.MethodsSix specimens with identical diameter (10 mm) and thickness (3 mm) were prepared from each self-adhesive and adhesive resin luting cement and forwarded to an incubation in various acidic media for a period of 232 h. Conductivity and pH-values of each acidic medium was analyzed for each material group prior (t 0) and after exposure (t 1). The specimens were examined for Vickers microhardness and surface quality. For the evaluation of surface roughness, the parameters Sa, Sdr, Spc Spk, Sk, and Svk were investigated by using different filtered surfaces (S-L; S-F) according to ISO 25 178. Statistical analysis was conducted at a significance level of α = 0.050.ResultsFor the evaluation of the acid resistance of self-adhesive resin luting cements investigations on conductivity and pH-value assessment of storage solution appear unsuitable, while the assessment of microhardness and surface analysis revealed valid data. It could be shown that changes in surface texture of the resin luting cements can be determinend in qualitative and quantitative manner. While the microhardness and surface quality of some resin luting cements hardly changed, others showed significantly reduced values in microhardness and changes in their surface quality (p < 0.001).SignificanceThe data of the current study emphasize the relevance of interactions between resin luting cements and acids and suggest further laboratory and clinical studies to elucidate its impact on the clinical performance of the materials investigated  相似文献   
4.
BackgroundAdherent perinephric fat (APF) contributes to surgical complexity and can be associated with adverse perioperative outcomes for partial nephrectomy (PN). The Mayo Adhesive Probability (MAP) score accurately predicts the presence of APF during robotic-assisted partial nephrectomy (RAPN). Our primary aim is to validate MAP score as a predictor of APF in open partial nephrectomy (OPNx).MethodsWe reviewed 105 consecutive OPNx (100 patients) performed by a single surgeon with intraoperative determination of APF. We evaluated the ability of the MAP score to discriminate between those with APF and those without APF by estimating the area under the receiver operating characteristic curve (AUROCC). The association of perioperative outcomes with APF was evaluated as well.ResultsForty-three patients [49%; 95% confidence interval (CI), 39–59%] had intraoperative identification of APF. The MAP score had excellent ability to predict APF in OPNx (AUROCC, 0.82; 95% CI, 0.74–0.92). APF was observed in 6% of patients with a MAP score of 0-1, 27% with score 2, 52% with score 3, 75% with score 4, and 90% with score 5. The presence of APF was associated with longer operative times (P=0.004) and higher estimated blood loss (EBL) (P=0.003). Although not statistically significant, our study did suggest that APF may be associated with postoperative complications and prolonged length of stay (LOS) (>3 days).ConclusionsMAP score accurately predicts the presence of APF in patients undergoing OPNx. APF is associated with longer operative time and higher blood loss in OPNx.  相似文献   
5.
《Orthodontic Waves》2019,78(3):93-101
PurposeThe purpose of this study was to make a systematic review and meta-analysis of studies investigated the effects of positional factors on the bonding failure of brackets.MethodsElectronic databases (PubMed, Web of science, Scopus) were searched by 3 independent researchers. Randomized studies comparing maxilla-mandibular region, anterior–posterior segments, and right-left arch were included in the meta-analysis. The odds ratio was used as the effect size. A two-tailed test was performed to compare the factors. Heterogeneity was calculated with the Cochran Q test and I2 statistics.ResultsAssociation was found between bonding failure and dental regions (OR = 1.24, 95% CI: 1.05, 1.46) (p = 0.009) and between bonding failure and anterior–posterior segments, too (OR = 1.96, 95% CI: 1.58, 2.45) (p < 0.001). But, no association was found bonding failure and arch sides (OR = 1.11, 95% CI: 0.96, 1.29) (p = 0.26).ConclusionClinicians should more care, especially when operating in the mandibular region and posterior segment. However, there is no difference between the left and right arch in terms of the loss of the bracket.  相似文献   
6.
7.
目的:观察小针刀联合拔罐疗法治疗肩周炎的临床疗效。方法:将2017年12月-2018年12月就诊于我院治未病中心的60例肩周炎患者随机分为治疗组30例,对照组30例,治疗组采用针刀联合拔罐,对照组采用普通针刺联合拔罐,两组治疗周期均为15 d,观察两组治疗前后临床总有效率和不良反应发生率。结果:两组经过15 d天治疗后,不良反应发生率相当,但治疗组总有效率明显高于对照组。结论:基于中医循经辨证取穴与西医病因病理及解剖定位相结合提高了针刀治疗肩周炎的治愈率。  相似文献   
8.
Objectives:To measure post-gel shrinkage, elastic modulus, and flexural strength of orthodontic adhesives and to predict shrinkage stress using finite element analysis (FEA).Materials and Methods:The following 6 orthodontic adhesives were tested: Transbond XT (3M Unitek, Monrovia, Calif), Transbond Plus Color Change (3M Unitek), Greengloo (Ormco, Brea, Calif), Ortho Connect (GC America, Alsip, Ill), Trulock (RMO, Denver, Colo), GoTo (Reliance, Itasca, Ill). Post-gel shrinkage was measured using a biaxial strain gauge during light curing. Elastic modulus and flexural strength were measured with a 4-point bending test. Analysis of variance and Student-Newman-Keuls post hoc tests were used to compare the shrinkage, elastic modulus, and flexural strengths among the materials (α = .05). Shrinkage stresses caused by the post-gel shrinkage and elastic modulus values were calculated using a cross-sectional FEA of a metallic bracket bonded to an incisor.Results:Properties were highly different among the adhesives (P ≤ .0001). Transbond XT (0.38 ± 0.09 percent volumetric contraction) and GoTo (0.42 ± 0.05 percent volumetric contraction) had the lowest post-gel shrinkage; Transbond Plus Color Change had the highest (0.84 ± 0.08 percent volumetric contraction). OrthoConnect (6.8 ± 0.6 gigapascals) had the lowest elastic modulus; GoTo (28.3 ± 3.1 gigapascals) had the highest. Trulock (64.1 ± 8.2 megapascals) had the lowest flexural strength; Greengloo (139.1 ± 20.7 megapascals) had the highest. FEA showed that the highest shrinkage stresses were generated with Transbond Plus Color Change and the lowest with OrthoConnect.Conclusions:Post-gel shrinkage of orthodontic adhesives was comparable with restorative composites, which are known to create shrinkage stresses in restored teeth. FEA indicated that this shrinkage creates stresses in the adhesive and in the enamel around the brackets.  相似文献   
9.
Helicobacter pylori have been subject to intense investigation since its discovery from gastric biopsy in 1982. This gastropathogen has been regarded as serious public health problem due to its association with dyspepsia, gastritis, gastroduodenal ulcers, mucus-associated lymphoid tissue lymphoma and gastric carcinoma. In vivo eradication of established H. pylori infections is difficult due to several factors such as gastric niche, coccoid form due to sub-minimum inhibitory concentration of antimicrobials, bacterial load, primary antibiotic resistance, patient compliance and stability of therapeutics in gastric acid secretion. Considering these factors, a logical way to improve the outcome of the treatment is to develop dosage forms which are able to deliver the anti-helicobacter agents in the gastric niche for both local and systemic actions, simultaneously taking care of stability of therapeutics in acidic environment. Such dosage forms, which are popularly known as gastro retentive drug delivery systems (GRDDS), have the immense potential to effectively counter the problem of high bacterial load; prevent induction of coccoid bacteria thereby improving treatment outcome and compliance. This review describes efficacy of various therapeutic agents, treatment strategies and status of different GRDDS until now.  相似文献   
10.
目的探讨严重粘连性小瞳孔白内障超声乳化术的安全性及手术技巧。方法对26例(32只眼)粘连性小瞳孔白内障,术中采用透明角膜切口,散瞳后瞳孔直径(2.5±0.5)mm。以晶状体调位钩及chopper钩辅助,松解粘连,扩大瞳孔至4~5 mm,连续环形撕囊后进行原位白内障超声乳化吸除及折叠人工晶状体植入。结果术后3个月随访,术眼视力均较术前提高,其中视力≥0.5者20只眼(62.5%)。术后患眼瞳孔接近圆形或椭圆形,部分患者瞳孔直径较术前偏大。但其中2只眼再发部分后粘连,1只眼后囊少许破裂,仍植入人工晶状体,无人工晶状体明显偏位。结论采用上述技术不仅顺利完成小瞳孔白内障超声乳化术,且手术安全有效,视力恢复较好,保持或接近生理性圆,手术并发症相对减少。  相似文献   
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