Tracing the toxic ions of an endodontic tricalcium silicate-based sealer in local tissues and body organs

BackgroundThis study aimed to track the toxic ions released by MTA Fillapex, BioRoot RCS, and an experimental tricalcium silicate-based sealer (CEO) into local and distant tissues as well as to investigate their potential adverse effects. In addition, the chemical constituents of the sealers were also evaluated. The main components of the dry powders, pastes, and mixed sealers were characterized.Material and methodsDry powder and sealer discs were each set for 72 h and their main components were characterized by energy dispersive X-ray spectroscopy. Polyethylene tubes filled with sealers were used to measure silicon and calcium ions. Polyethylene tubes filled with sealers or empty tubes were implanted into the dorsal connective tissue of Wistar rats. On days 7, 15, 30, and 45, the animals were euthanized and their brains, livers, kidneys, and subcutaneous tissues were removed and processed to determine the concentrations of chromium, cobalt, copper, lead, iron, magnesium and nickel using an inductively coupled plasma optical emission spectrometer.ResultsThe main compounds in all sealers were carbon, oxygen, silicon, and calcium. MTA Fillapex release more Si while highest levels of Si were found in presence of BioRoot. The release of Si and Ca ions promoted by MTA Fillapex raise by time. No traces of cobalt, chromium, or magnesium were detected in any tissue. Irrespective of the sealer, no traces of copper and lead were found in the subcutaneous tissue; however, they were observed in the organs. The highest concentration of iron was identified in the liver. All sealers exhibited similar nickel traces in the brain, kidney, and liver except for MTA Fillapex, which demonstrated levels higher than CEO in the subcutaneous tissue on day 7. Tracing nickel ions over time revealed that lowest concentrations were found in subcutaneous tissue.ConclusionTaken together, our data demonstrate that CEOs have chemical compositions similar to those of other commercial sealers. Furthermore, none of them exhibited a threat to systemic health. Moreover, the minimal amounts of iron and nickel detected were not related to the sealers.     

不同根管器械去除弯曲根管内充填物的效果研究

目的:比较新型旋转器械马尼GPR和ProTaper再治疗系统、手用H锉在根管再治疗中去除弯曲根管内牙胶的清理效果。方法:选取30个弯曲度为30°的透明树脂根管模块,根管长度为17mm。使用ProTaper Next机用镍钛器械预备至30/.06,热压胶垂直加压根管充填。样本随机分为3组(n=10),用以下方法配合丁克除溶剂去除根管内充填材料,A组手用H锉、B组ProTaper再治疗系统和C组马尼GPR,记录去除充填物所用总时间。从颊舌向和近远中向2个角度拍着数码X线片,使用Image J 2X图像分析软件分析根管内充填物残留量。用天平称量推出根尖孔碎屑量。结果:ProTaper再治疗系统组根管壁充填物残留量明显多于马尼GPR组和H锉组(P0.05)。H锉组操作时间明显高于ProTaper再治疗系统组和马尼GPR组(P0.05)。马尼GPR组推出根尖孔碎屑量明显少于ProTaper再治疗系统组(P0.05)。结论:马尼再治疗锉去除根管内充填物效率优于ProTaper再治疗系统和H锉,机用镍钛器械所用时间明显少于手用器械。     

Analysis of Resin-Dentin Interface Morphology and Bond Strength Evaluation of Core Materials for One Stage Post-Endodontic Restorations

PurposeRestoration of endodontically treated teeth using fiber posts in a one-stage procedure gains more popularity and aims to create a secondary monoblock. Data of detailed analyses of so called “post-and-core-systems” with respect to morphological characteristics of the resin-dentin interface in combination with bond strength measurements of fiber posts luted with these materials are scarce. The present study aimed to analyze four different post-and-core-systems with two different adhesive approaches (self-etch and etch-and-rinse).ResultsCLSM analyses revealed significant differences between groups with respect to the factors hybrid layer thickness (p<0.0005) and number of resin tags (p = 0.02; ANOVA). Bond strength was significantly affected by core material (p = 0.001), location inside the root canal (p<0.0005) and incorporation of fluorescent dyes (p = 0.036; ANOVA). CX [7.7 (4.4) MPa] demonstrated significantly lower bond strength compared to LC [14.2 (8.7) MPa] and RB [13.3 (3.7) MPa] (p<0.05; Tukey HSD) but did not differ significantly from MC [11.5 (3.5) MPa].ConclusionIt can be concluded that bond strengths inside the root canal were not affected by the adhesive approach of the post-and-core-system. All systems demonstrated homogenous hybrid layer formation and penetration into the dentinal tubules in spite of the complicating conditions for adhesion inside the root canal.     

MTA、iRoot BP Plus及氢氧化钙在年轻恒牙活髓切断术中临床疗效的比较分析

摘要 目的：研究三氧化矿物凝聚体（MTA）、iRoot BP Plus（iRooT）以及氢氧化钙（Ca(OH) ₂）三种材料在年轻恒牙活髓切断术中的临床疗效。方法：将60例需要接受年轻恒牙活髓切断术的患者（60颗患牙）按照使用材料不同随机分为三组：MTA组、iRooT组和Ca（OH）₂组,每组20例（20颗患牙）,比较三组患者术后3个月和6个月手术成功率、牙本质桥形成和牙齿变色发生率、牙根管壁厚度、牙齿功能和美观度、以及血清基质金属蛋白酶-3（MMP-3）和白细胞介素-8（IL-8）水平。结果：（1）三组患者仅术后6个月临床治疗成功率存在显著差异（P<0.05）;（2）Ca（OH）₂组术后牙本质桥形成率显著低于其他两组（P<0.05）,而牙齿变色发生率显著低于MTA组（P<0.05）和显著高于iRooT组（P<0.05）。（3）三组患者治疗后牙根管壁厚度均较治疗前显著增加,且治疗后Ca（OH）₂组患牙根管壁厚度增加显著低于MTA组和iRooT组（P<0.05）。（4）Ca（OH）2组患者术后6个月牙齿舒适功能、固定功能和咀嚼功能评分均显著低于MTA组和iRooT组（P<0.05）,而牙齿美观度评分显著低于iRooT组（P<0.05）和显著高于MTA组（P<0.05）。（5）三组患者术后6个月血清MMP-3和IL-8均显著低于术前（P<0.05）,并且MTA组患者血清MMP-3和IL-8水平显著高于iRooT组（P<0.05）和显著低于CaOH组（P<0.05）。结论：iRoot BP Plus和MTA材料应用于年轻恒牙活髓切断术均具有较高的远期成功率,但MTA材料远期牙齿变色率较高因而影响牙齿美观度。     

Effect of repeated microwave disinfections on bonding of different commercial teeth to resin denture base

doi: 10.1111/j.1741‐2358.2011.00516.x Effect of repeated microwave disinfections on bonding of different commercial teeth to resin denture base Objective: To verify the influence of repeated microwave disinfections on the shear bond strength of two commercial types of teeth to acrylic resin, when the ridge lap surfaces were unmodified, bur abraded, bur grooved or etched by monomer. Material and methods: Eighty specimens (n = 10) were adhered to the tooth ridge lap surface, polymerised in a water bath at 74°C for 9 h. Microwaved specimens were individually immersed in 150 ml of water and submitted to five simulated disinfections in a microwave oven calibrated at 650 W for 3 min. Control specimens were not microwave treated. Shear bond strength tests were performed in an Instron machine with a cross‐speed of 1 mm/min. The fracture load values were transformed into shear bond strength as a function of the bonding area (0.28 cm²). Data were submitted to anova and Tukey’s test (α = 0.05). Fractured areas were classified as adhesive, cohesive (resin or tooth) or mixed failures. Results: Repeated microwave disinfections increased the shear strength of the tooth/resin bond. Mechanical retention in microwaved and non‐microwaved procedures improved the shear bond strength. Conclusions: The different commercial types of teeth influenced shear bond strength values, with Biotone teeth showing the lower values.     

热牙胶充填与冷牙胶侧方加压在根管充填中应用的临床效果比较

目的:比较热牙胶充填与冷牙胶侧方加压在根管充填中应用的临床效果。方法:选择62例急性牙髓炎和根尖周炎患者,均分后分别选择热牙胶充填与冷牙胶侧方加压的方法进行根管充填,比较两组患者根管充填时间、术后牙周疼痛病例和术后3个月后充填质量及临床疗效。结果:两组患者术后牙周疼痛病例比较,差异无统计学意义(P>0.05);其余各方面比较,差异均均有统计学意义(P>0.05),热牙胶组优于冷牙胶组。结论:临床进行根管充填治疗时,应首选热牙胶充填的方式,可显著提高临床疗效,且不增加患者术后牙周疼痛的发生。     

Comparative evaluation of nano-filled and conventional adhesives for bonding of molar tubes

It is of interest to compare the bonding characteristics of the two nano filled adhesives, Grandio (Voco, Cuxhaven, Germany) and Transbond Supreme LV (TSLV, 3M Unitek, Monrovia, California) with conventional bonding adhesive Transbond XT (TBXT, 3M Unitek) for bonding of molar tubes. 45 extracted human permanent molar teeth, divided into three groups of 15 each, were bonded with stainless steel molar tubes (3M Unitek, USA) using TBXT in Group 1, Grandio in Group 2, TSLV in Group 3. Remnant Index and shear bond strength was evaluated after 24 hrs. of storage with the aid of Instron Universal testing machine and Stereomicroscope respectively. Data were analysed using Analysis of Variance (ANOVA) test, Post-hoc Bonferroni test and Kruskal Wallis test. The mean SBS of Group 1(TBXT) was 13.86±3.27 MPa, Group 2 (Grandio) was 9.48±2.36 MPa and Group 3 (TSLV) was 11.64±2.71 MPa. Both nano-filled adhesives had SBS well above the clinically acceptable range. Assessment of ARI scores and type of bond failure revealed that adhesive failure for TBXT and TSLV and cohesive failure for Grandio. Nano-filled adhesives can be an appropriate substitute for the conventional adhesive for bonding of molar tubes.     

A Cone-Beam Computed Tomographic Study on Mandibular First Molars in a Chinese Subpopulation

The purpose of this study was to conduct a cone-beam computed tomographic (CBCT) investigation on the root and canal configuration of the mandibular first molars, especially the morphology of the disto-lingual (DL) root, in a Chinese subpopulation. A total of 910 CBCT images of the mandibular first molars were collected from 455 patients who underwent CBCT examinations as a preoperative assessment for implants or orthodontic treatment. The following information was analyzed and evaluated: tooth position, gender, root and root canal number per tooth, root canal type of the mesial root(s) and distal root(s), angle of the DL root canal curvature, distance between two distal canal orifices in the teeth with DL root, and angle of disto-buccal canal orifice–disto-lingual canal orifice–mesio-lingual canal orifice (DB-DL-ML). Most of the mandibular first molars (64.9%, n = 591) had two roots with three root canals, and most of the mesial root canals (87.7%, n = 798) were type VI. The prevalence of the DL root was 22.1% (n = 201). The right side had a higher prevalence of DL root than the left side (p<0.05). Additionally, the curvature of the DL root canal were greater in the bucco-lingual (BL) orientation (30.10°±14.02°) than in the mesio-distal (MD) orientation (14.03°± 8.56°) (p<0.05). Overall there was a high prevalence of DL root in the mandibular first molars, and most of the DL roots were curved in different degrees. This study provided detailed information about the root canal morphology of the mandibular first molars in a Chinese subpopulation.     

预酸蚀乳牙牙本质对自酸蚀粘接系统粘接强度的影响

目的:探讨预酸蚀乳牙牙本质对自酸蚀粘接系统粘接强度的影响。方法:随机选取28颗健康乳磨牙,磨除颊舌面釉质,暴露牙本质粘接面,沿近远中向劈开形成56个样本,随机分为7组(n=8)。直接涂布组(A1组,A2组和A3组)分别涂布AdperTM Easy One(AEO),Xeno-V(XV)和OptiBond All In One(AIO)三种自酸蚀粘接剂,预酸蚀组(B1组,B2组和B3组)在涂布三种自酸蚀粘接剂前先使用35%磷酸酸蚀乳牙牙本质15 s,对照组(C组)使用Prime&Bond NTTM(NT)全酸蚀粘接剂,每个样本用Z350复合树脂堆砌成直径为3 mm的树脂小柱,通过剪切试验测试剪切粘接强度,并通过扫描电子显微镜观察断裂表面形态。结果:B1组,B2组的剪切粘接强度值明显高于A1组,A2组(P<0.001);B3组与A3组的剪切粘接强度值比较无明显差别(P=0.94)。A2组的剪切粘接强度值低于C组(P<0.05);B1组的剪切粘接强度值明显高于C组(P<0.001)。扫描电镜观察结果显示各组试件断裂面形态多为牙本质和复合树脂界面破坏。直接涂布组(A1组,A2组和A3组)断裂多发生在混合层的底部,树脂突较少且低于小管口。B1组和B2组试件断裂面可见多数牙本质小管被树脂突填满,断裂多发生在混合层的中上部。B3组试件断裂面可见牙本质小管空虚,树脂突较少。结论:预酸蚀乳牙牙本质可以提高AEO,XV两种自酸蚀粘接剂的剪切粘接强度。自酸蚀粘接剂处理乳牙牙本质可以达到全酸蚀粘接剂处理的粘接强度,但应用自酸蚀粘接剂前预酸蚀乳牙牙本质可以获得更高的粘接强度。     

Effects of Type I Collagen Degradation on the Durability of Three Adhesive Systems in the Early Phase of Dentin Bonding

ObjectiveThis study was designed to evaluate the effects of type I collagen degradation on the durability of three adhesive systems in the early phase of dentin bonding.MethodsBonded dentin specimens were prepared using three different types of adhesive systems. Micro-tensile bond strength and degradation of collagen were tested before, and after 1 month or 4 months of aging in artificial saliva. The relationship between micro-tensile bond strength and collagen degradation was analyzed by calculating their Pearson’s correlation coefficient.ResultsAging induced time-dependent reduction in micro-tensile bond strengths for all the tested adhesive systems, although such reduction for the single-step self-etching adhesive G-Bond (GB) was not statistically significant. The bond strength of the two-step self-etching primer adhesive system Clearfil SE Bond (SEB) was similar to that of the two-step etch-and-rinse self-priming adhesive system Single Bond 2 (SB), and they were both significantly reduced after one or four months of aging. A negative correlation was found between the degree of collagen degradation and magnitude of micro-tensile bond strength (r = - 0.65, p = 0.003). The Pearson’s correlation coefficient was 0.426, indicating that 42.6% of the aging-induced reduction in bond strength can be explained by the degradation of collagen.ConclusionsIn the early phase of dentin bonding, there was a negative correlation between the degree of collagen degradation and the magnitude of micro-tensile bond strength. The reduction of bond strength was accompanied by the degradation of collagen. These results provide evidence for the causative relationship between the degradation of collagen and the deterioration of dentin-adhesive interface.     

Effect of Er,Cr:YSGG Laser at Different Output Powers on the Micromorphology and the Bond Property of Non-Carious Sclerotic Dentin to Resin Composites

Background

The objective of this study was to investigate the influence of Er,Cr:YSGG laser irradiated at different powers on the micromorphology and the bonding property of non-carious sclerotic dentin to resin composites.

Methods

Two hundred bovine incisors characterized by non-carious sclerotic dentin were selected, and the seventy-two teeth of which for surface morphological analysis were divided into nine groups according to various treatments (A: the control group, B: only treated with the adhesive Adper Easy One, C: diamond bur polishing followed by Adper Easy One, D-I: Er,Cr:YSGG laser irradiating at 1W, 2W, 3W, 4W, 5W, 6W output power, respectively, followed by Adper Easy One). The surface roughness values were measured by the non-contact three-dimensional morphology scanner, then the surface micromorphologies of surfaces in all groups were assessed by scanning electron microscopy (SEM); meanwhile, Image Pro-Plus 6.0 software was used to measure the relative percentage of open tubules on SEM images. The rest, one hundred twenty-eight teeth for bond strength test, were divided into eight groups according to the different treatments (A: only treated with the adhesive Adper Easy One, B: diamond bur polishing followed by the above adhesive, C-H: Er,Cr:YSGG laser irradiating at 1 W, 2 W, 3 W, 4 W, 5 W, 6 W output power, respectively, followed by the above adhesive), and each group was subsequently divided into two subgroups according to whether aging is performed (immediately tested and after thermocycling). Micro-shear bond strength test was used to evaluate the bond strength.

Results

The 4W laser group showed the highest roughness value (30.84±1.93μm), which was statistically higher than the control group and the diamond bur groups (p<0.05). The mean percentages ((27.8±1.8)%, (28.0±2.2)%, (30.0±1.9)%) of open tubules area in the 4W, 5W, 6W group were higher than other groups (p<0.05). The 4W laser group showed the highest micro-shear bond strength not only in immediately tested (17.60±2.55 PMa) but after thermocycling (14.35±2.08MPa).

Conclusion

The Er,Cr:YSGG laser at 4W power can effectively improve the bonding property between non-carious sclerotic dentin and resin composites by increasing the roughness and mean percentage area of open tubules.     

Molecular mechanisms determining the strength of receptor-mediated intermembrane adhesion.

The strength of receptor-mediated cell adhesion is directly controlled by the mechanism of cohesive failure between the cell surface and underlying substrate. Unbinding can occur either at the locus of the specific bond or within the bilayer, which results in tearing the hydrophobic anchors from the membrane interior. In this work, the surface force apparatus has been used to investigate the relationship between the receptor-ligand bond affinities and the dominant mechanism of receptor-coupled membrane detachment. The receptors and ligands used in this study were membrane-bound streptavidin and biotin analogs, respectively, with solution affinities ranging over 10 orders of magnitude. With the optical technique of the surface force apparatus, the occurrence of membrane rupture was directly visualized in situ. The latter observations together with measurements of the corresponding intermembrane adhesive strengths were used to identify the dominant failure pathway for each streptavidin-analog pair. Even in cases where the membrane pull-out energy exceeded the equilibrium bond energy, cohesive failure occurred within the membrane interior at nearly all bond affinities considered. These results are consistent with previous findings and provide direct support for the commonly held view that, under nonequilibrium conditions of applied external stress, the gradient of the bond energy, not the equilibrium bond energy alone, determines the adhesive strength.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effectiveness of a WHO self‐help psychological intervention for preventing mental disorders among Syrian refugees in Turkey: a randomized controlled trial

Refugees are at high risk of developing mental disorders. There is no evidence from randomized controlled trials (RCTs) that psychological interventions can prevent the onset of mental disorders in this group. We assessed the effectiveness of a self‐help psychological intervention developed by the World Health Organization, called Self‐Help Plus, in preventing the development of mental disorders among Syrian refugees experiencing psychological distress in Turkey. A two‐arm, assessor‐masked RCT was conducted in two Turkish areas. Eligible participants were adult Syrian refugees experiencing psychological distress (General Health Questionnaire ≥3), but without a diagnosis of mental disorder. They were randomly assigned either to the Self‐Help Plus arm (consisting of Self‐Help Plus combined with Enhanced Care as Usual, ECAU) or to ECAU only in a 1:1 ratio. Self‐Help Plus was delivered in a group format by two facilitators over five sessions. The primary outcome measure was the presence of any mental disorder assessed by the Mini International Neuropsychiatric Interview at six‐month follow‐up. Secondary outcome measures were the presence of mental disorders at post‐intervention, and psychological distress, symptoms of post‐traumatic stress disorder and depression, personally identified psychological outcomes, functional impairment, subjective well‐being, and quality of life at post‐intervention and six‐month follow‐up. Between October 1, 2018 and November 30, 2019, 1,186 refugees were assessed for inclusion. Five hundred forty‐four people were ineligible, and 642 participants were enrolled and randomly assigned to either Self‐Help Plus (N=322) or ECAU (N=320). Self‐Help Plus participants were significantly less likely to have any mental disorders at six‐month follow‐up compared to the ECAU group (21.69% vs. 40.73%; Cramer''s V = 0.205, p<0.001, risk ratio: 0.533, 95% CI: 0.408‐0.696). Analysis of secondary outcomes suggested that Self‐Help Plus was not effective immediately post‐intervention, but was associated with beneficial effects at six‐month follow‐up in terms of symptoms of depression, personally identified psychological outcomes, and quality of life. This is the first prevention RCT ever conducted among refugees experiencing psychological distress but without a mental disorder. Self‐Help Plus was found to be an effective strategy for preventing the onset of mental disorders. Based on these findings, this low‐intensity self‐help psychological intervention could be scaled up as a public health strategy to prevent mental disorders in refugee populations exposed to ongoing adversities.     

Effect of sealer coating on mechanical and physical properties of permanent soft lining materials

doi: 10.1111/j.1741‐2358.2011.00487.x
Effect of sealer coating on mechanical and physical properties of permanent soft lining materials Objective: To evaluate the long‐term effects of sealer coating on tensile bond strength and surface roughness of soft liners. Background: Failure of the bond between resilient liners and denture base significantly compromise the dentures’ longevity. In addition, surface roughness contributes to bacterial adherence on prosthetic materials, increasing the risk of oral infections. Methods: Specimens were manufactured from four reliners [Mucopren Soft (MS), Dentuflex (DF); Soft Comfort Denso (SC) and Ufi Gel SC (USC)], distributed into 10 groups (n = 10), according to material and coating treatment. Tensile bond strength was performed after one year of ageing, while surface roughness was evaluated at 0, 1, 3, 6 and 12 ageing months. Bond strength data were submitted to two‐way anova and Tukey‐HSD tests, while roughness data were submitted to mixed model analysis for repeated measurements (p ≤ 0.05). Results: MS and DF without sealer coating presented the highest tensile bond strength. After coating, DF and SC presented increased tensile bond strength. No surface roughness difference was observed in the non‐coated groups over time, acrylic‐based reliners presented higher roughness. Among coated groups, only SC presented increased surface roughness. Acrylic‐based materials presented reduced roughness at three months. Conclusion: Surface coating was effective for acrylic reliners in maintaining their initial properties. However, sealer coating should be re‐applied every 3 months.     

Physico-chemical and antimicrobial properties and the shelf life of experimental endodontic sealers containing metal methacrylates

Abstract

The objective of this study was to evaluate the physico-chemical and antimicrobial properties of a dual polymerization experimental endodontic sealer (E) and experimental sealers containing dibutyltin methacrylate (Sn²⁺) (ETs) or calcium methacrylate (Ca²⁺) (ECs). The pH and ion release levels of the sealers were measured. The dimensional stability was evaluated in accordance with ISO 6876. Biofilm growth inhibition was evaluated using confocal laser scanning microscopy (CLSM). Biofilm viability analysis was performed using the SYTO 9 technique. The shelf life was evaluated through the degree of conversion and film thickness tests after the sealers had been stored for different periods of time. For statistical analysis, ANOVA and Tukey’s post hoc test were used, with a significance level of 5%. ETs revealed better anti-biofilm potential after 15?days than that of the controls. The degree of conversion was reduced after the shelf-life period. The addition of calcium and dibutyltin methacrylate improved the anti-biofilm properties of the experimental endodontic sealer without impairing their physico-chemical properties.     

The prevalence of increased serum IgE and Aspergillus sensitization in patients with COPD and their association with symptoms and lung function

Background

Allergy and Aspergillus hypersensitivity (AH) were shown to be associated with severe symptoms or worse lung function in COPD patients. The prevalence of elevated total IgE (T-IgE) and its association with clinical symptoms and lung function in COPD have not been studied. The prevalence of AH and its correlation with clinical characteristics in a COPD cohort of larger sample size is also lacking.

Methods

273 patients with COPD were evaluated by respiratory symptoms, blood test, chest HRCT, lung function, serum detection of T-IgE and Aspergillus specific IgE. Patients with T-IgE ≥ 1000 KU/L were further investigated for allergic bronchopulmonary aspergillosis (ABPA).

Results

The prevalence of elevated T-IgE and AH in patients with COPD was 47.3% and 15.0%, respectively. Eight patients (2.9%) met the diagnostic criteria for ABPA. Compared with the normal T-IgE group, patients with elevated T-IgE had a longer history of dyspnea (p < 0.01), an earlier onset of dyspnea after chronic cough/expectoration (p < 0.01), and were more likely to wheeze (p < 0.01). They also showed worse lung functions and more severe GOLD staging (p < 0.01). Analysis of the clinical data in male patients with smoking as the risk factor showed the same results. To evaluate the clinical characteristics of COPD with AH, patients with elevated T-IgE were further divided into subgroups with and without AH. When compared with the normal T-IgE group, both the two subgroups showed longer history of dyspnea (p < 0.01), an earlier onset of dyspnea (p < 0.01) and a worse status of lung function (p < 0.05). Correlation analysis demonstrated that T-IgE was correlated positively with the time length of dyspnea (r = 0.401, p < 0.001), and the ratio of duration of dyspnea to that of chronic cough/expectoration (r = 0.59, p < 0.001), but negatively with FEV1/FVC% (r = −0.194, p = 0.001), and FEV1%predicted (r = −0.219, p < 0.001).

Conclusions

There was a high prevalence of elevated serum T-IgE and AH in patients with COPD. Serum T-IgE level was correlated with symptoms such as dyspnea and impairment of lung function. Allergens other than Aspergillus may have similar effects on disease expression or progression of COPD.     

Bonding of Resin Cement to Zirconia with High Pressure Primer Coating

Objectives

To investigate the effect of air-drying pressure during ceramic primer coating on zirconia/resin bonding and the surface characteristics of the primed zirconia.

Methods

Two ceramic primers (Clearfil Ceramic Primer, CCP, Kuraray Medical Inc. and Z-Prime Plus, ZPP, Bisco Inc.) were applied on the surface of air-abraded zirconia (Katana zirconia, Noritake) and dried at 4 different air pressures (0.1–0.4 MPa). The primed zirconia ceramic specimens were bonded with a resin-based luting agent (SA Luting Cement, Kuraray). Micro-shear bond strengths of the bonded specimens were tested after 3 days of water storage or 5,000× thermocycling (n = 12). Failure modes of the fractured specimens were examined with scanning electron miscopy. The effects of air pressure on the thickness of the primer layers and the surface roughness (S_a) of primed zirconia were evaluated using spectroscopic ellipsometry (n = 6), optical profilometry and environmental scanning electron microscopy (ESEM) (n = 6), respectively.

Results

Clearfil Ceramic Primer air-dried at 0.3 and 0.4 MPa, yielding significantly higher µSBS than gentle air-drying subgroups (p<0.05). Compared to vigorous drying conditions, Z-Prime Plus air-dried at 0.2 MPa exhibited significantly higher µSBS (p<0.05). Increasing air-drying pressure reduced the film thickness for both primers. Profilometry measurements and ESEM showed rougher surfaces in the high pressure subgroups of CCP and intermediate pressure subgroup of ZPP.

Conclusion

Air-drying pressure influences resin/zirconia bond strength and durability significantly. Higher air-drying pressure (0.3-0.4 MPa) for CCP and intermediate pressure (0.2 MPa) for ZPP are recommended to produce strong, durable bonds between resin cement and zirconia ceramics.     

Posterior Atrophy and Medial Temporal Atrophy Scores Are Associated with Different Symptoms in Patients with Alzheimer’s Disease and Mild Cognitive Impairment

Background

Whether the occurrence of posterior atrophy (PA) and medial temporal lobe atrophy (MTA) was correlated with cognitive and non-cognitive symptoms in Alzheimer’s disease (AD) and mild cognitive impairment (MCI) patients are unclear.

Methods

Patients with probable AD and MCI from a medical center outpatient clinic received attention, memory, language, executive function evaluation and Mini-Mental Status Examination (MMSE). The severity of dementia was rated by the Clinical Dementia Rating (CDR) Sum of Box (CDR-SB). The neuropsychiatric inventory (NPI) subscale of agitation/aggression and mood symptoms was also applied. Magnetic resonance imaging (MRI) was scored visually for the MTA, PA and white matter hyperintensity (WMH) scores.

Results

We recruited 129 AD and 31 MCI (mean age 78.8 years, 48% female) patients. MMSE scores, memory, language and executive function were all significantly decreased in individuals with AD than those with MCI (p < 0.01). MTA and PA scores reflected significant atrophy in AD compared to MCI; however, the WMH scores did not differ. The MTA scores were significantly correlated with the frontal, parieto-occipital and global WMH scores (p < 0.01) while the PA scores showed a correlation with the parieto-occipital and temporal WMH scores (p < 0.01). After adjusting for age, education, APOE4 gene and diagnostic group covariates, the MTA scores showed a significant association with MMSE and CDR-SB, while the right side PA scores were significantly associated with NPI-agitation/aggression subscales (p < 0.01).

Conclusion

Regional atrophy is related to different symptoms in patients with AD or MCI. PA score is useful as a complementary measure for non-cognitive symptom.     

The Influence of Casing-Sand Adhesion on Cementing Bond Strength

In the petroleum industry, one of the most serious problems encountered during cementing is the failure at the bonding interface. Many measures including casing-sand adhesion have been developed to improve cementing bond strength. However, due to the lack of detailed study of the technique, many questions remain. The primary goal of this study is to investigate the influence of casing-sand adhesion on cementing bond strength, and to optimize parameters. An orthogonal experiment and a supplementary experiment were conducted. The results indicated that casing-sand adhesion can improve the cementing bond strength. The priority orders of key factors are: sand grain size, sand coverage, adhesive curing temperature and adhesive curing time. The optimal parameters recommended for application are: 1.6mm~1.9mm sand grain size, 60%~70% sand coverage, 30°C curing temperature and 60 hours curing time.     

Effect of root canal sealers on mouse peritoneal macrophage functions

Three root canal filling materials, viz. calcium hydroxide-based cement (Apexit, resin-based cement (AH-plus) and glass-ionomer based material (Ketac Endo) were tested for their influence on several functions of peritoneal macrophages from Balb/c mice. Macrophage functions were evaluated by the adherence, phagocytic, candidacidal and Nitro blue tetrazolium-dye assays. Ketac-Endo enhanced all macrophage functions in the first 2 d (p < or = 0.05), when compared to the positive control, but this effect had changed after 7 and 14 d, causing inhibition of these functions. Other materials suppressed substrate adherence capacity and phagocytosis, while significantly stimulating macrophage microbicidal activity (p < or = 0.05) in a time-dependent manner.