Cementation

胶结
  • 文章类型: Journal Article
    随着老年人髋部骨折发生率的增加,骨水泥股骨柄髋关节置换术已成为一种可行的治疗选择.然而,对潜在并发症的担忧,特别是骨水泥植入综合征(BCIS),尤其是在已有疾病的患者中,促使骨科医生探索替代方法。
    这项回顾性研究的研究问题是,在接受骨水泥双极人工股骨头置换术的先前存在心脏病的患者中,BCIS的发生率是否高于没有先前存在心脏病的患者。
    我们回顾性分析了311例接受骨水泥双极人工股骨头置换术的患者的数据,包括188个没有预先存在的心脏病和123个有心脏病。回顾麻醉记录以评估与BCIS相关的参数。BCIS严重程度进行了系统分级,强调关键指标,比如低血压,动脉去饱和,以及意识的丧失.
    在患者中,无围手术期死亡发生。13例患者(4.18%)观察到1级BCIS,没有2级或3级的实例。值得注意的是,仅在2例已有心脏病患者(1.63%)和11例无心脏病患者(5.85%)中观察到1级BCIS.
    骨水泥双极半髋关节置换术后BCIS的发生率很低,严重程度主要较低。重要的是,先前存在的心脏病并未显著增加BCIS的风险.这一发现证实了老年人骨水泥双极半髋关节置换术的安全性。
    III.
    UNASSIGNED: With the increasing incidence of hip fractures in older adults, hip replacement with a cemented femoral stem has become a viable treatment option. However, concerns regarding potential complications, particularly bone cement implantation syndrome (BCIS), especially in patients with preexisting medical conditions, have prompted orthopedic surgeons to explore alternative approaches.
    UNASSIGNED: The research question of this retrospective study is whether BCIS incidence in patients with preexisting heart disease undergoing cemented bipolar hemiarthroplasty is higher than that of patients without preexisting heart disease.
    UNASSIGNED: We retrospectively analyzed data from 311 patients undergoing cemented bipolar hemiarthroplasty, including 188 without preexisting heart disease and 123 with heart disease. Anesthetic records were reviewed to assess parameters related to BCIS. BCIS severity was graded systematically, emphasizing key metrics, such as hypotension, arterial desaturation, and the loss of consciousness.
    UNASSIGNED: Among the patients, no perioperative deaths occurred. Grade 1 BCIS was observed in 13 patients (4.18 %), without instances of grade 2 or 3. Notably, grade 1 BCIS was observed in only 2 patients with preexisting heart disease (1.63%) and 11 patients (5.85%) without preexisting heart disease.
    UNASSIGNED: BCIS incidence after cemented bipolar hemiarthroplasty was minimal, with a predominantly low severity. Importantly, preexisting heart disease did not pose a significant increase in the risk of BCIS. This finding confirms the safety of cemented bipolar hemiarthroplasty in older adults.
    UNASSIGNED: III.
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  • 文章类型: Journal Article
    目的:评估三种临时胶泥的恢复损失率,生物相互作用,美学属性,和处理特性。
    方法:75名需要固定口腔修复的成年人自愿参加了单盲手术,随机对照试验。准备之后,用随机选择的临时修补水泥(ProvicolQMPlus(PQP),BifixTemp(BT),或ProvicolQM美学(PQA))。在胶结后一到两周进行临床检查。评估了以下标准:牙齿活力,打击乐器,超敏反应,牙龈出血,气味形成,美学,水泥处理,可移除性,可清洁性,和保留损失。拮抗牙齿作为对照。采用配对t检验进行统计学分析,单向方差分析,皮尔森卡方检验和费舍尔精确检验,在适当的地方。
    结果:临时修复的总体损失率为16.0%,显示没有水泥特异性差异。无论水泥类型如何,术后过敏均发生在8%的病例中。31%的PQP固定修复体报告了美学损伤,与BT和PQA粘结修复体的4.0%和4.2%相比。据报道,在100%的情况下,水泥应用很容易,过量去除88-96%,取决于使用的水泥。
    结论:选择luting材料会影响临时修复的美学外观,应予以考虑,特别是在美学要求苛刻的区域的修复。在生物相容性方面,水泥之间没有显著差异。处理,和损失率。
    结论:半透明水泥有助于减少颜色干扰,导致临时修复的外观更具吸引力。
    OBJECTIVE: To evaluate three temporary luting cements in terms of their restoration loss rates, biological interactions, esthetic properties, and handling characteristics.
    METHODS: 75 adults requiring fixed prosthodontics voluntarily participated in a single-blind, randomized controlled trial. After preparation, temporary restorations were luted with a randomly selected temporary luting cement (either Provicol QM Plus (PQP), Bifix Temp (BT), or Provicol QM Aesthetic (PQA)). Clinical examinations were performed one to two weeks after cementation. The following criteria were evaluated: tooth vitality, percussion, hypersensitivity, gingival bleeding, odor formation, esthetics, cement handling, removability, cleanability, and retention loss. Antagonistic teeth served as controls. Statistical analysis was performed using the paired t-test, one-way ANOVA, Pearson\'s chi-square and Fisher\'s exact test, where appropriate.
    RESULTS: The overall loss rate of temporary restorations was 16.0%, showing no cement-specific differences. Postoperative hypersensitivity occurred in 8% of cases regardless of cement type. Esthetic impairment was reported by 31% of the PQP-fixed restorations, compared with 4.0% and 4.2% of the BT and PQA-bonded restorations. Cement application was reported to be easy in 100% of cases, excess removal in 88-96%, depending on the cement used.
    CONCLUSIONS: The choice of luting material affects the esthetic appearance of a temporary restoration and should be considered, particularly in restorations in esthetically demanding areas. No significant differences between the cements were identified regarding biocompatibility, handling, and loss rate.
    CONCLUSIONS: Translucent cements can help to reduce color interferences, resulting in a more appealing appearance of the temporary restoration.
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  • 文章类型: Journal Article
    氧化锆的粘附是困难的;因此,正在开发使用几种不同方法的蚀刻剂。我们研究了用市售蚀刻剂进行表面处理对氧化锆与树脂水泥之间粘结强度的影响,并将其与仅使用空气磨蚀获得的效果进行了比较。我们用了100个氧化锆块,其中20块未经处理,20块被喷砂处理,和60块使用三种不同的氧化锆蚀刻系统进行酸蚀刻:Zircos-E蚀刻(强酸蚀刻),智能蚀刻(空气磨损后的酸蚀刻),和云蚀刻(在热流下的酸蚀刻)。每组都用双重聚合树脂水泥进行粘合程序,然后对50个样本进行热循环。评估了热循环前后树脂水泥与氧化锆之间的剪切粘结强度。我们观察到,在没有进行热循环的组中,与喷砂试样相比,用溶液表面处理的试样的剪切粘结强度没有显着增加(p>0.05)。在热循环的群体中,智能蚀刻试样显示出最高的剪切粘结强度。在短期内,与单独喷砂相比,各种蚀刻剂的粘结强度没有显着增加,但从长远来看,智能蚀刻显示粘结强度稳定(p<0.05)。
    Adhesion of zirconia is difficult; thus, etching agents using several different methods are being developed. We investigated the effects of surface treatment with commercially available etching agents on the bond strength between zirconia and resin cement and compared them with those achieved using air abrasion alone. We used 100 zirconia blocks, of which 20 blocks remained untreated, 20 blocks were sandblasted, and 60 blocks were acid-etched using three different zirconia-etching systems: Zircos-E etching (strong-acid etching), smart etching (acid etching after air abrasion), and cloud etching (acid etching under a hot stream). Each group was subjected to a bonding procedure with dual-polymerized resin cement, and then 50 specimens were thermocycled. The shear bond strengths between the resin cement and zirconia before and after the thermocycling were evaluated. We observed that in the groups that did not undergo thermocycling, specimens surface-treated with solution did not show a significant increase in shear bond strength compared to the sandblasted specimens (p > 0.05). Among the thermocycled groups, the smart-etched specimens showed the highest shear bond strength. In the short term, various etching agents did not show a significant increase in bond strength compared to sandblasting alone, but in the long term, smart etching showed stability in bond strength (p < 0.05).
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  • 文章类型: Journal Article
    目的:为了研究使用不同陶瓷材料制造的前腔内修复体的抗断裂性和失效模式,并使用各种胶结方法粘结。
    方法:根据所使用的陶瓷材料,将40颗上颌中切牙分为两个主要组;组I(Zir):氧化锆内分泌(ZolidHT,Ceramill,Amanngirrbach)和GroupII(E-Max):e-max内冠(IPSe.maxCAD,IvoclarVivadent)。根据胶结方案,将两组进一步分为两个亚组;IA亚组“ZirMDP”:用MDP底漆+MDP树脂水泥胶结的内胎,IB亚组(ZirNon-MDP):用MDP底漆+非MDP树脂水泥胶结,IIA亚组(E-maxMDP):用MDP底漆+MDP树脂水泥胶结,IIB亚组(E-maxNon-MDP):用MDP底漆+非MDP树脂水泥胶结。(n=10/亚组)。使用CAD/CAM制造内皮。牙齿经受10,000个热循环。在45o处以腭力方向进行骨折测试,直到发生骨折。测试结果以牛顿记录。使用立体显微镜检查故障模式。利用单向ANOVA测试来比较关于断裂强度值的不同组。Tukey的PostHoc被用于多重比较。
    结果:不同组的断裂强度比较分析得出的差异不显著,如p值超过0.05所示。尽管如此,关于故障模式出现了一个可观察到的趋势。具体来说,在所有组的牙釉质交界处(CEJ)下方的内冠状/牙齿复合体内的骨折均具有统计学意义,除了IIB组,\"E-max非MDP,“内冠状/牙齿复合体内的骨折发生在CEJ上方。
    结论:将基于MDP的底漆与基于MDP的树脂粘固剂结合使用不会对前腔内骨折强度产生显著影响。
    结论:无论组合物中是否存在MDP单体,当与MDP基陶瓷底漆一起使用时,粘合剂树脂水泥获得了非常成功的断裂强度。此外,表现出超过牙本质的弹性模量的陶瓷材料是不鼓励的,因为它们倾向于在牙齿结构内引起灾难性的骨折。
    OBJECTIVE: To investigate the fracture resistance and failure modalities of anterior endocrown restorations fabricated employing diverse ceramic materials, and bonded using various cementation methodologies.
    METHODS: Forty maxillary central incisors were divided into two main groups based on the ceramic materials used; GroupI (Zir): zirconia endocrwons (Zolid HT+, Ceramill, Amanngirrbach) and GroupII (E-Max): e-max endocrowns (IPS e.max CAD, Ivoclar Vivadent). Both groups were further split into two subgroups depending on the cementation protocols; subgroup IA \"ZirMDP\": endocowns cemented with MDP primer + MDP resin cement, subgroup IB (ZirNon-MDP): cemented with MDP primer + non-MDP resin cement, subgroup IIA (E-maxMDP): cemented with MDP primer + MDP resin cement, subgroup IIB (E-maxNon-MDP): cemented with MDP primer + non-MDP resin cement. (n = 10/subgroup). Endocrowns were manufactured using CAD/ CAM. Teeth were subjected to 10,000 thermal cycles. The fracture test was performed at 45o with a palatal force direction until the fracture occurred. Test results were recorded in Newton. The failure mode was examined using a stereomicroscope. A One-way ANOVA test was utilized to compare different groups regarding fracture strength values. Tukey`s Post Hoc was utilized for multiple comparisons.
    RESULTS: The comparative analysis of fracture strength across the diverse groups yielded non-significant differences, as indicated by a p-value exceeding 0.05. Nonetheless, an observable trend emerged regarding the mode of failure. Specifically, a statistically significant prevalence was noted in fractures localized within the endocrown/tooth complex below the cementoenamel junction (CEJ) across all groups, except for Group IIB, \"E-max Non-MDP,\" where fractures within the endocrown/tooth complex occurred above the CEJ.
    CONCLUSIONS: Combining an MDP-based primer with an MDP-based resin cement did not result in a significant effect on the anterior endocrown fracture strength.
    CONCLUSIONS: Regardless of the presence of the MDP monomer in its composition, adhesive resin cement achieved highly successful fracture strength when used with MDP-based ceramic primers. Additionally, ceramic materials exhibiting elastic moduli surpassing those of dentin are discouraged due to their propensity to induce catastrophic fractures within the tooth structure.
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  • 文章类型: Journal Article
    进行这项研究是为了评估使用常规的双重固化树脂水泥或自粘树脂水泥胶结至根管牙本质时,重新连接和非重新连接的玻璃纤维桩的机械性能。
    使用了两种类型的树脂水泥:常规和自粘。此外,采用了2种胶结方案,涉及加固和非加固玻璃纤维柱。总的来说,对72个牛门牙进行胶结,并进行了推出粘结强度测试(n=10),然后进行了破坏模式分析。沿根管评估横截面显微硬度(n=5),和界面分析(n=3)使用扫描电子显微镜(SEM)进行。通过3向方差分析和Bonferroni事后检验(α=0.05)分析了推出粘结强度和横截面显微硬度测试的数据。
    对于非中继玻璃纤维支柱,常规树脂水泥比自粘水泥具有更高的挤出粘结强度。相关的玻璃纤维柱在树脂粘固剂之间产生了可比的结果。II型失效是两种树脂水泥最常见的失效模式,无论胶结方案如何。重新连接的玻璃纤维柱的使用改善了两种水泥的横截面显微硬度值。SEM图像显示门牙中的空隙和气泡与未保留的玻璃纤维桩。
    机械性能受到胶结方案的影响。Relined玻璃纤维柱具有最高的推出粘结强度和横截面显微硬度值,无论使用的树脂水泥(传统的双重固化或自粘)。相反,对于非加固玻璃纤维柱,传统的双重固化树脂水泥比自粘树脂水泥效果更好。
    UNASSIGNED: This study was conducted to evaluate the mechanical properties of relined and non-relined fiberglass posts when cemented to root canal dentin using a conventional dual-cure resin cement or a self-adhesive resin cement.
    UNASSIGNED: Two types of resin cements were utilized: conventional and self-adhesive. Additionally, 2 cementation protocols were employed, involving relined and non-relined fiberglass posts. In total, 72 bovine incisors were cemented and subjected to push-out bond strength testing (n = 10) followed by failure mode analysis. The cross-sectional microhardness (n = 5) was assessed along the root canal, and interface analyses (n = 3) were conducted using scanning electron microscopy (SEM). Data from the push-out bond strength and cross-sectional microhardness tests were analyzed via 3-way analysis of variance and the Bonferroni post-hoc test (α = 0.05).
    UNASSIGNED: For non-relined fiberglass posts, conventional resin cement exhibited higher push-out bond strength than self-adhesive cement. Relined fiberglass posts yielded comparable results between the resin cements. Type II failure was the most common failure mode for both resin cements, regardless of cementation protocol. The use of relined fiberglass posts improved the cross-sectional microhardness values for both cements. SEM images revealed voids and bubbles in the incisors with non-relined fiberglass posts.
    UNASSIGNED: Mechanical properties were impacted by the cementation protocol. Relined fiberglass posts presented the highest push-out bond strength and cross-sectional microhardness values, regardless of the resin cement used (conventional dual-cure or self-adhesive). Conversely, for non-relined fiberglass posts, the conventional dual-cure resin cement yielded superior results to the self-adhesive resin cement.
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  • 文章类型: Journal Article
    目的:植入物松动是髋关节翻修术中最常见的茎翻修适应症。这项研究比较了股骨骨丢失和骨水泥和未骨水泥松动的主茎之间的初始修正的风险,探讨一期植入固定方法对股骨骨缺损的影响。
    方法:这项回顾性研究回顾了255例患者,这些患者在2010年至2022年期间接受了骨水泥或非骨水泥的茎植入物进行了首次茎松动翻修。术前使用Poprosky分类通过影像学评估测量股骨骨丢失。Kaplan-Meier分析估计了原始茎的生存概率,风险比评估了术后第一年和随后2-10年中非骨水泥和骨水泥茎的相对翻修风险。
    结果:胶结茎显示出较高的明显骨丢失发生率(3b型和4型缺损:32.39%vs.2.72%,p<.001)与未成型茎相比,更常见的是1型和2型缺陷(82.07%vs.47.89%,p<.001)。在我们对修订案例的分析中,与骨水泥茎相比,原发非骨水泥茎在植入后第一年表现出茎松动发生率低20%(HR0.8;95%-CI0.3-2.0).然而,在随后的2~10年中,未接合茎的发病率增加了20%(HR1.2;95%-CI0.7-1.8).脓毒症松动在骨水泥茎中更为常见(28.17%vs.10.87%在非胶结茎中,p=.001)。Kaplan-Meier分析显示,在植入后的前十年内,骨水泥茎的无翻修期较长(p<.022)。
    结论:在第一次修订期间,骨水泥茎显示的股骨骨缺损明显大于非骨水泥茎。在胶结茎中,败血症茎松动的发生率增加了17.30%。
    OBJECTIVE: Implant loosening represent the most common indication for stem revision in hip revision arthroplasty. This study compares femoral bone loss and the risk of initial revisions between cemented and uncemented loosened primary stems, investigating the impact of fixation method at primary implantation on femoral bone defects.
    METHODS: This retrospective study reviewed 255 patients who underwent their first revision for stem loosening from 2010 to 2022, receiving either cemented or uncemented stem implants. Femoral bone loss was preoperatively measured using the Paprosky classification through radiographic evaluations. Kaplan-Meier analysis estimated the survival probability of the original stem, and the hazard ratio assessed the relative risk of revision for uncemented versus cemented stems in the first postoperative year and the following two to ten years.
    RESULTS: Cemented stems showed a higher prevalence of significant bone loss (type 3b and 4 defects: 32.39% vs. 2.72%, p < .001) compared to uncemented stems, which more commonly had type 1 and 2 defects (82.07% vs. 47.89%, p < .001). In our analysis of revision cases, primary uncemented stems demonstrated a 20% lower incidence of stem loosening in the first year post-implantation compared to cemented stems (HR 0.8; 95%-CI 0.3-2.0). However, the incidence in uncemented stems increased by 20% during the subsequent years two to ten (HR 1.2; 95%-CI 0.7-1.8). Septic loosening was more common in cemented stems (28.17% vs. 10.87% in uncemented stems, p = .001). Kaplan-Meier analysis indicated a modestly longer revision-free period for cemented stems within the first ten years post-implantation (p < .022).
    CONCLUSIONS: During first-time revision, cemented stems show significantly larger femoral bone defects than uncemented stems. Septic stem loosening occurred 17.30% more in cemented stems.
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  • 文章类型: Journal Article
    背景:在螺钉松动的情况下,回收水泥保留的植入物支持的修复体很有趣。检测螺钉进入孔(SAH)的估计尺寸可以减少对假体的破坏并保留牙冠。
    目的:通过胶结牙冠精确定位松动的种植体螺钉,以减少螺钉松动后牙冠的损伤。
    方法:在这项体外研究中,60个水泥保留植入物支持30个氧化锆基,并发明了30个陶瓷与金属(CFM)下磨牙冠,每个被细分为三个子组(每个10个)。在I组(AI/BI)(对照组)中,SAH是在骨科造影术(OPG)的帮助下创建的。相比之下,在第II组(氧化锆冠)中,SAH是在IIA/IIIA亚组中在具有2mm金属套管的CBCT+3D打印手术导向器的帮助下创建的,并且CBCT+MAR用于在IIB/IIIB亚组中开发SAH。SEM和Micro-CT扫描SAH开口以确定孔的直径,cracking,削片,和碎裂的音量。
    结果:关于平面CBCT和CBCT+MAR对预备冠的影响,检测到I组与II组(p=0.001)和III组(p=0.002)之间存在高度显著的相关性.关于SAH的开裂,发现锆冠和CFM修复之间存在显着差异(p=0.009),而对于削片,组间无显著关联(p=0.19).
    结论:CBCT,作为飞机CBCT或MAR,显著提高了螺钉通道的钻孔精度,减少了对现有修复体和基台的损伤,帮助SAH在松动的种植体基台螺钉中更好地定位。
    BACKGROUND: Retrieval of cement-retained implant-supported restorations is intriguing in cases of screw loosening. Detecting the estimated size of the screw access hole (SAH) could decrease destruction to the prosthesis and preserve the crown.
    OBJECTIVE: To precisely localize loose implant screws through cemented crowns to reduce crown damage after screw loosening.
    METHODS: In this in vitro study, 60 cement-retained implants supported 30 zirconia-based, and 30 ceramics fused to metal (CFM) lower molar crowns were invented, and each was subdivided into three subgroups (10 each). In group I (AI/BI) (control), SAH was created with the aid of orthopantomography (OPG). In contrast, in group II (zirconia-crown), SAH was created with the aid of CBCT + 3D printed surgical guide with a 2 mm metal sleeve in subgroups IIA/IIIA and CBCT + MAR was used to develop SAH in subgroups IIB/IIIB. SEM and Micro-CT scanned the SAH openings to determine the diameter of the hole, cracking, chipping, and chipping volume.
    RESULTS: Regarding the effect of plane CBCT and CBCT + MAR on prepared crowns, a highly significant association between group I with group II (p = 0.001) and group III (p = 0.002) was detected. Regarding the cracking of SAH, significant differences between the zirconium crown and CFM restoration (p = 0.009) were found, while for the chipping, no significant association was seen between groups (p = 0.19).
    CONCLUSIONS: CBCT, either as a plane CBCT or with MAR, significantly improved the accuracy of drilling the screw channel and decreased injury to the existing restoration and abutment, aiding in better localization of SAH in loosened implant abutment screws.
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  • 文章类型: Journal Article
    为保证矿山采空区的充填效果,提高生态基质胶结煤矸石膏体充填材料的稳定性,将聚丙烯纤维均匀掺入到碱活化矿渣粉煤灰地聚合物中。然后在各种条件下进行三轴压缩试验。研究了复合膏体充填材料的力学性能和损伤特性,建立了膏体充填材料在三轴压缩作用下的损伤演化模型,基于样品渐进破坏行为产生的偏应力-应变曲线。通过使用SEM-EDS和XRD微观技术阐明和理解了结构和特征演变的内部物理和化学机理。结果表明,在试验研究范围内,纤维能有效提高试样的极限强度和相应的有效应力强度指标。当NaOH用量为固体材料质量的3%时,强化效果最佳,纤维的量为固体材料质量的5‰,纤维的长度约为12mm。样品中纤维的作用方式主要分为单握锚固和三维网状牵引。随着裂缝的开始和发展,连接发生在矩阵中,其中光纤对裂纹扩展有明显的干扰和延迟效应,从而将脆性破坏转化为延性破坏,从而改善生态胶凝煤矸石基质的断裂性能。以初始压实阶段终点为临界点,构建分段充填体损伤演化理论模型,得到了不同条件下试样的损伤演化模型曲线。三轴压缩试验结果验证了理论模型的正确性。我们得出结论,实验曲线与理论曲线吻合良好。因此,所建立的理论模型对膏体充填材料力学性能的分析与评价具有一定的参考价值。研究结果可以提高固体废物资源的利用率。
    Polypropylene fiber was equally mixed into alkali-activated slag fly ash geopolymer in order to ensure the filling effect of mine goaf and improve the stability of cemented gangue paste filling material with ecological matrix. Triaxial compression tests were then conducted under various conditions. The mechanical properties and damage characteristics of composite paste filling materials are studied, and the damage evolution model of paste filling materials under triaxial compression is established, based on the deviatoric stress-strain curve generated by the progressive failure behavior of samples. Internal physical and chemical mechanisms of the evolution of structure and characteristics are elucidated and comprehended via the use of SEM-EDS and XRD micro-techniques. The results show that the fiber can effectively improve the ultimate strength and the corresponding effective stress strength index of the sample within the scope of the experimental study. The best strengthening effect is achieved when the amount of NaOH is 3% of the mass of the solid material, the amount of fiber is 5‰ of the mass of the solid material, and the length of the fiber is about 12 mm. The action mode of the fiber in the sample is mainly divided into single-grip anchoring and three-dimensional mesh traction. As the crack initiates and develops, connection occurs in the matrix, where the fiber has an obvious interference and retardation effect on the crack propagation, thereby transforming the brittle failure into a ductile failure and consequently improving the fracture properties of the ecological cementitious coal gangue matrix. The theoretical damage evolution model of a segmented filling body is constructed by taking the initial compaction stage end point as the critical point, and the curve of the damage evolution model of the specimen under different conditions is obtained. The theoretical model is verified by the results from the triaxial compression test. We concluded that the experimental curve is in good agreement with the theoretical curve. Therefore, the established theoretical model has a certain reference value for the analysis and evaluation of the mechanical properties of paste filling materials. The research results can improve the utilization rate of solid waste resources.
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  • 文章类型: Journal Article
    背景:水泥垫片对于补偿烧结收缩后氧化锆修复的变形至关重要,允许适当的座位和更好的抗断裂修复。文献中缺少评估水泥垫片对氧化锆骨架的配合精度和断裂强度的影响的研究。因此,这项研究的目的是评估不同水泥垫片设置对3单位和4单位氧化锆骨架的配合精度和断裂强度的影响。
    方法:用2个制备的基台制造了60个标准化的不锈钢母模,用于制造3单元和4单元的氧化锆框架。根据水泥垫片设置将框架分为6组(n=10)(30μm,50μm,和80μm)如下:3单元框架;3u-30、3u-50、3u-80和4单元框架;4u-30、4u-50和4u-80。使用复制方法评估框架的拟合准确性。标本被粘在相应的模具上,并在万能试验机上测量断裂强度。计算研究组的Weibull参数,并检查断裂试样的失效模式。双向方差分析,然后进行Tukey检验,以进行研究组之间的成对比较(α=0.05)。
    结果:水泥垫片对3单元和4单元框架的配合精度和断裂强度均具有显着影响。50μm垫片具有明显更好的配合精度,其次是80μm,和30μm垫片。50μm和80μm间隔物具有相似的断裂强度,两者的强度均明显优于30μm垫片。
    结论:对于3单位和4单位氧化锆骨架,50μm水泥垫片可以推荐超过30μm和80μm垫片,以显著提高配合精度和足够的断裂强度。
    BACKGROUND: Cement spacer is essential for compensating deformation of zirconia restoration after sintering shrinkage, allowing proper seating and better fracture resistance of the restoration. Studies assessing the effect of cement spacer on fit accuracy and fracture strength of zirconia frameworks are missing in the literature. Therefore, the aim of this study was to evaluate the effect of different cement spacer settings on fit accuracy and fracture strength of 3-unit and 4-unit zirconia frameworks.
    METHODS: Sixty standardized stainless-steel master dies were manufactured with 2 prepared abutments for fabricating 3-unit and 4-unit zirconia frameworks. The frameworks were assigned into 6 groups (n = 10) according to cement spacer setting (30 μm, 50 μm, and 80 μm) as follows: 3-unit frameworks; 3u-30, 3u-50, 3u-80, and 4-unit frameworks; 4u-30, 4u-50, and 4u-80. The frameworks were assessed for fit accuracy with the replica method. The specimens were cemented to their corresponding dies, and the fracture strength was measured in a universal testing machine. The Weibull parameters were calculated for the study groups and fractured specimens were inspected for failure mode. Two-Way ANOVA followed by Tukey test for pairwise comparison between study groups (α = 0.05).
    RESULTS: The cement spacer had a significant effect on both fit accuracy and fracture strength for 3-unit and 4-unit frameworks. The 50 μm spacer had significantly better fit accuracy followed by 80 μm, and 30 μm spacers. Both 50 μm and 80 μm spacers had similar fracture strength, and both had significantly better strength than 30 μm spacer.
    CONCLUSIONS: For both 3-unit and 4-unit zirconia frameworks, 50 μm cement spacer can be recommended over 30 μm and 80 μm spacers for significantly better fit accuracy and adequate fracture strength.
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  • 文章类型: Journal Article
    MICP大规模应用的主要挑战在于其低效率,促进生物膜生长可以有效解决这一问题。在本研究中,利用响应面法建立了预测模型。有了预测模型,可以获得培养基中营养素的最佳浓度。此外,通过生物胶结试验将优化的培养基与其他培养基进行比较。结果表明,该预测模型是准确有效的,预测结果与实测结果接近。通过使用预测模型,确定了优化的培养基(20.0g/l酵母提取物,10.0g/l聚蛋白胨,5.0g/l硫酸铵,和10.0g/lNaCl)。此外,与其他培养基相比,优化的培养基显著促进了生物膜的生长。在媒介中,聚蛋白胨对生物膜生长的影响小于酵母提取物的影响,增加聚蛋白胨的浓度不利于促进生物膜的生长。此外,用优化介质固化的砂柱强度最高,碳酸钙含量最大。预测模型代表了一种平台技术,该技术利用培养基来赋予新颖的感知,adjusttive,以及在土木工程和材料工程领域对结构材料的多功能响应。
    The main challenge in the large-scale application of MICP lies in its low efficiency and promoting biofilm growth can effectively address this problem. In the present study, a prediction model was proposed using the response surface method. With the prediction model, optimum concentrations of nutrients in the medium can be obtained. Moreover, the optimized medium was compared with other media via bio-cementation tests. The results show that this prediction model was accurate and effective, and the predicted results were close to the measured results. By using the prediction model, the optimized culture media was determined (20.0 g/l yeast extract, 10.0 g/l polypeptone, 5.0 g/l ammonium sulfate, and 10.0 g/l NaCl). Furthermore, the optimized medium significantly promoted the growth of biofilm compared to other media. In the medium, the effect of polypeptone on biofilm growth was smaller than the effect of yeast extract and increasing the concentration of polypeptone was not beneficial in promoting biofilm growth. In addition, the sand column solidified with the optimized medium had the highest strength and the largest calcium carbonate contents. The prediction model represents a platform technology that leverages culture medium to impart novel sensing, adjustive, and responsive multifunctionality to structural materials in the civil engineering and material engineering fields.
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