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1.
《Dental materials》2020,36(1):119-134
ObjectiveThe aim of this systematic review and meta-analysis was to evaluate the effect of surface conditioning methods on the bond strength of industrial indirect composite blocks (ICs).MethodsBased on the PICOS strategy, the Medline via PubMed, Embase and Web of Science (ISI – Web of Knowledge) electronic databases were searched for peer-reviewed articles in both English and Chinese, with no publication year limit. In vitro studies evaluating the effects of surface conditioning on the bond strength of ICs were selected. The meta-analysis was conducted to calculate the mean difference between surface-conditioned ICs and unconditioned controls. Subgroup analysis was performed to evaluate the different surface conditioning methods, separately for polymer-infiltrated ceramic network (PICN) material and the ICs with dispersed fillers (ICDFs). Meta-analyses were performed with a random-effects model at a significance level of 0.05.Results and SignificanceFrom 802 relevant studies, 25 were selected for full-text analysis. Nineteen studies were eligible for inclusion in this systematic review, whereas 9 studies were included in the meta-analysis. A manual search of the principal periodicals specific to the area resulted in no additional articles. The meta-analysis indicated a significant difference in bond strength between the surface-conditioned ICs and controls under both non-aged and aged conditions. The combination of mechanical and chemical conditioning yielded the highest bond strength of ICs. This meta-analysis suggests that chemical etching followed by a universal primer and alumina air abrasion followed by a silane coupling agent could be considered the best strategy for optimizing the bond strength of PICN materials and ICDFs under aged conditions, respectively. 相似文献
2.
目的:探讨口腔粘结技术对儿童下颌骨骨折的治疗效果。方法:对37例儿童下颌骨骨折应用复合树脂粘结固定夹板,其中 4例应用复合树脂直接固定;13例实施尼龙丝结扎-复合树脂固定夹板;12例实施贴钩-尼克丝-复合树脂固定;3例应用金属丝弓一复合树脂单颌固定;5例实施牙列贴钩 带钩丝弓-复合树脂颌间弹性牵引。结果:37例儿童下颌骨骨折中有35例咬合关系恢复正常,2例 有轻度错(牙合),经调(牙合)后咬合关系正常。结论:儿童混合牙列时期乳、恒牙交替及牙齿形态特殊,又儿童下颌骨中含有牙胚不易手术治疗,而常规牙弓夹板固定困难,因此,应用复合树脂粘结固定夹板治疗儿童下颌骨骨折是一项简易、高效的技术。 相似文献
3.
目的 :研究粘接剂对降低银汞合金充填体微渗漏的作用 ,以评价其在充填治疗中的意义 ,探讨减少银汞合金充填体边缘微渗漏的有效方法。方法 :选择无龋的离体牙 30颗 ,制备相同的洞型 ,随机分成实验组和对照组。实验组在牙洞各壁先涂上Super Band粘接剂后再用银汞合金充填 ,对照组不涂粘接剂而直接用银汞合金充填。用染色渗入法比较两组间的微渗漏情况。结果 :实验组银汞合金充填体的边缘微渗漏明显低于对照组 (P<0 .0 1 )。结论 :Super-Band粘接剂能够明显降低银汞合金充填体的微渗漏 相似文献
4.
目的 了解硬质树脂贴面与三种粘结剂的粘结强度。方法 选用21颗中切牙随机分成三组(n=7),制作硬质树脂贴面,用不同的粘结剂粘固。第1组:EM釉质粘结剂;第2组:京津釉质粘合剂;第3组:光固化树脂,粘结后置入37℃温水中24小时后,用电子多功能测试机进行拉伸试验。结果 三种粘结剂与硬质树脂粘结拉伸强度无差异,光固化树脂与硬质树粘接力大于与釉质的粘接力,京津釉质粘结剂与硬质树脂粘结力小于与釉质的粘接力;EM釉质粘结剂与硬质树脂和釉质的粘结力近似一个水平。结论 三种粘结剂粘接硬质树脂贴面是可行的。 相似文献
5.
Smith J Plaat F Fisk NM 《BJOG : an international journal of obstetrics and gynaecology》2008,115(8):1037-1042
Although much effort has gone into promoting early skin-to-skin contact and parental involvement at vaginal birth, caesarean birth remains entrenched in surgical and resuscitative rituals, which delay parental contact, impair maternal satisfaction and reduce breastfeeding. We describe a 'natural' approach that mimics the situation at vaginal birth by allowing (i) the parents to watch the birth of their child as active participants (ii) slow delivery with physiological autoresuscitation and (iii) the baby to be transferred directly onto the mother's chest for early skin-to-skin. Studies are required into methods of reforming caesarean section, the most common operation worldwide. 相似文献
6.
目的观察喷砂、酸蚀及硅烷偶联剂等表面处理方法对热压铸陶瓷,玻璃渗透陶瓷和氧化锆陶瓷与不同种粘结剂的粘接强度的影响。方法样本分为热压铸陶瓷组,渗透陶瓷组和氧化锆陶瓷组。每组各20片,各组中再随机分为A,B,C,D4小组,每组5片。分别应用不同种表面处理方法和粘结剂,测其剪切强度。结果方差分析表明热压铸陶瓷组中酸蚀涂硅烷树脂粘结组粘接强度最高,喷砂玻璃离子粘结组粘接强度最低。渗透陶瓷组中喷砂玻璃离子粘结组粘接强度最高,酸蚀涂硅烷树脂粘结组粘接强度最低。氧化锆陶瓷组中喷砂玻璃离子粘结组粘接强度最高,酸蚀涂硅烷树脂粘结组粘接强度最低。结论应用常规树脂粘结剂粘固热压铸陶瓷修复体取得较好的粘同效果,采用酸蚀和硅烷偶联剂的表面处理可取得最大粘结强度。但常规树脂粘结剂粘固渗透陶瓷和氧化锆陶瓷修复体取得的粘固效果不理想。临床上应根据全瓷修复体的种类选择适当的粘结剂系统和表面处理方式。 相似文献
7.
作者考察了四种测试条件对牙本质粘接强度的影响,包括牙的新鲜程度、牙的重复使用次数、粘接部位以及拉伸负载速度。采用GP牙本质粘接材料,结果表明:粘接部位和拉伸负载速度与粘接强度没有明显的关系,牙的新鲜程度和重复使用次数与粘接强度有很大关系。牙拔出后贮存过久、使用次数越多,粘接强度超低,作粘接试件的牙的贮存期不应超过1月,且牙只能使用一次。 相似文献
8.
Little is known regarding the longitudinal effects of bonding and bridging social capital on health. This study examined the longitudinal associations of bonding and bridging social capital with self-rated health, depressive mood, and cognitive decline in community-dwelling older Japanese. Data analyzed in this study were from the 2010 (baseline) and 2012 (follow-up) Hatoyama Cohort Study. Bonding social capital was assessed by individual perception of homogeneity of the neighborhood (the level of homogeneity among neighbors) and of networks (the amount of homogeneous personal networks) in relation to age, gender, and socioeconomic status. Bridging social capital was assessed by individual perception of heterogeneity of networks (the amount of heterogeneous personal networks) in relation to age, gender, and socioeconomic status. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the effects of baseline social capital on poor health outcome at follow-up by logistic regression analysis. In total, 681 people completed baseline and follow-up surveys. The mean age of participants was 71.8 ± 5.1 years, and 57.9% were male. After adjusting for sociodemographics, lifestyle factors, comorbidity, functional capacity, baseline score of each outcome, and other bonding/bridging social capital, stronger perceived neighborhood homogeneity was inversely associated with poor self-rated health (OR = 0.55, 95% CI = 0.30–1.00) and depressive mood assessed by the Geriatric Depression Scale (OR = 0.58, 95% CI = 0.34–0.99). When participants who reported a depressive mood at baseline were excluded, stronger perceived heterogeneous network was inversely associated with depressive mood (OR = 0.40, 95% CI = 0.19–0.87). Neither bonding nor bridging social capital was significantly associated with cognitive decline assessed by the Mini-Mental State Examination. In conclusion, bonding and bridging social capital affect health in different ways, but they both have beneficial effects on the health of older Japanese. Our findings suggest that intervention focusing on bonding and bridging social capital may improve various health outcomes in old age. 相似文献
9.
《Dental materials》2021,37(11):1734-1750
ObjectiveTo assess the microtensile bond strength (MTBS) and interfacial characteristics of universal adhesives applied on dentine air-abraded using different powders. The analysis includes the cytotoxicity of the powders and their effect on odontogenic gene expression.MethodsSound human dentine specimens were air-abraded using bioglass 45S5 (BAG), polycarboxylated zinc-doped bioglass (SEL), alumina (AL) and submitted to SEM analysis. Resin composite was bonded to air-abraded or smear layer-covered dentine (SML) using an experimental (EXP) or a commercial adhesive (ABU) in etch&rinse (ER) or self-etch (SE) modes. Specimens were stored in artificial saliva (AS) and subjected to MTBS testing after 24 h and 10 months. Interfacial nanoleakage assessment was accomplished using confocal microscopy. The cytotoxicity of the powders was assessed, also the total RNA was extracted and the expression of odontogenic genes was evaluated through RT-PCR.ResultsAfter prolonged AS storage, specimens in the control (SML) and AL groups showed a significant drop in MTBS (p > 0.05), with degradation evident within the bonding interface. Specimens in BAG or SEL air-abraded dentine groups showed no significant difference, with resin-dentine interfaces devoid of important degradation. The metabolic activity of pulp stem cells was not affected by the tested powders. SEL and BAG had no effect on the expression of odontoblast differentiation markers. However, AL particles interfered with the expression of the odontogenic markers.SignificanceThe use of bioactive glass air-abrasion may prevent severe degradation at the resin-dentine interface. Unlike alumina, bioactive glasses do not interfere with the normal metabolic activity of pulp stem cells and their differentiation to odontoblasts. 相似文献
10.
Breast cancers that are found and confirmed because they are causing symptoms tend to be larger and are more likely to have already spread to the lymph nodes and beyond. Thus, early detection and confirmation are of paramount importance. The normalized axial–shear strain area (NASSA) feature from the axial-shear strain elastogram (ASSE) has been shown to be a feature that can identify the boundary-bonding conditions that are indicative of the presence of cancer. Recently, we investigated and reported on the potential of the NASSA feature for breast lesion classification into fibroadenomas and cancers. In this article, we investigate the size distribution of the lesions that were part of the previous study and analyze classification performance specifically on small lesions (<10 mm diameter). A total of 33 biopsy-proven malignant tumors and 30 fibroadenomas were part of the study that involved three observers blinded to the Breast Imaging Reporting and Data System (BIRADS) ultrasound scores. The observers outlined the lesions on the sonograms and the lesion size (maximum circle-equivalent diameter in millimeters) was computed from this outline. The ASSE was automatically segmented and color-overlaid on the sonogram, and the NASSA feature from ASSE was computed semi-automatically. Receiver operating characteristic curves were then generated for the subset of cases involving small lesions. Box plots were produced for the two different lesion size groups, small and large, from a logistic regression classifier that was built previously. The results of our study show that approximately 38% and 22% of the fibroadenomas and cancers, respectively, were small. Furthermore, it was found that the NASSA feature resulted in a perfect classification of the small lesions, both in the training data and in the cross-validation. For lesions <10 mm the difference in fibroadenoma and cancer mean scores was 0.73 ± 0.13 (p < 0.001), whereas lesions >10 mm had a difference of 0.52 ± 0.24 (p < 0.001). The results also showed that the small lesions actually had better classification than the larger lesions (>10 mm). These results suggest that the ASSE feature can work equally well, even on small lesions, to improve the standard ultrasound BIRADS–based breast lesion classification of fibroadenoma and malignant tumors. 相似文献