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关键词： CAD-CAM   cell viability   contact angle   surface roughness   Y-TZP zirconia  

摘要： Objective: To evaluate the effect of the deterioration of computer aided design/computer aided manufacturing (CAD/CAM) burs during zirconia milling, on surface roughness, contact angle, and fibroblast viability. Materials and Methods: Ceramic blocks were milled and 75 ceramic disks (8 x 1.5 mm) made and allocated into three groups (n = 25): G1-brand new 2L and 1L burs, G2-2L bur at the end of lifetime and brand new 1L bur and G3-both burs at the end of their lifetimes. Roughness (Ra, Rq, and Rz) was evaluated using a 3D optical profilometer, the contact angle by the sessile drop method and the cell viability of the mouse NIH/3T3 fibroblast, using the Alamar Blue assay at intervals of 24, 48, and 72 h (ISO 10993-5). Data were analyzed by one-way ANOVA and Kruskal-Wallis tests (p <= 0.05). Results: Roughness increased as the burs deteriorated and G3 (0.27 +/- 0.04) presented a higher value for Ra (p < 0.001). The highest contact angle was observed in G3 (86.2 +/- 2.66) when compared with G1 (63.7 +/- 12.49) and G2 (75.3 +/- 6.36) (p < 0.001). Alamar Blue indicated an increase in cell proliferation, with no significant differences among the groups at 24 and 72 h (p > 0.05). Conclusions: The deterioration of the burs increased the surface roughness and decreased the wettability, but did not interfere in cell viability and proliferation. Clinical Significance: The use of custom zirconia abutments represents an effective strategy for single crowns restorations. Our findings suggest that these abutments can be efficiently milled using CAD/CAM burs within their recommended lifetime.

标准号: GB/T 44722-2024

摘要： 本文件描述了采用气相色谱-质谱联用仪（GC-MS）测定纺织品中喹啉残留量的试验方法。 本文件适用于各类纺织产品。

关键词： CAD/CAM   Dental material   Biomechanical behaviour   Tilted abutment  

摘要： Background Failure to restore missing teeth in time can easily lead to the mesial tilting of the distal abutment teeth. However, a fixed partial denture (FPD) can improve stress conduction and distribution and prevent periodontal injuries. In these more complex cases, it is necessary to consider various factors comprehensively to improve conventional treatment planning and achieve better results. Methods We selected a patient with a missing first molar and a mesial inclination of the second molar, leaving inadequate space or bone mass for implant denture restoration, necessitating an FPD for restoration. Three-dimensional finite element analysis (3D-FEA) combined with photoelastic analysis were used to explore how the inclination angle (0 - 30 degrees) and different dental restoration materials (zirconia, lithium disilicate, polymer-infiltrated ceramic network, and resin composite) affect the biomechanical behaviour of FPD-abutments-periodontal tissue complex. Results The stress was easily concentrated in the FPD connectors, enamel shoulder collar, periapical area, and root bifurcation. The stress on FPD and the periodontal ligament (PDL) of the second premolar increased with an increase in the elastic modulus of FPD, with an opposite trend in the abutments, the alveolar bone, and the PDL of the second molar. The stress on the FPD and alveolar bone increased with increased inclination angle of the distal abutment. The stress on two abutments and their PDL were positively correlated with the inclination angle in two stages;however, when the inclination angle > 12 degrees, the second premolar and its PDL showed a negative correlation. Conclusions FPDs can be used for restoration within 24 degrees of distal abutment inclination, but protecting the abutments (< 12 degrees especially) and the periodontal tissue (> 12 degrees especially) must be taken seriously. For this purpose, an FPD material with higher strength is recommended.

关键词： Patient-derived organoids   PDX   CAM   In ovo   [Ga-68]Ga-Pentixafor   2-[F-18]FDG   PET/MRI   CRC  

摘要： Background Patient-derived tumour organoids (PDOs) are highly advanced in vitro models for disease modelling, yet they lack vascularisation. To overcome this shortcoming, organoids can be inoculated onto the chorioallantoic membrane (CAM);the highly vascularised, not innervated extraembryonic membrane of fertilised chicken eggs. Therefore, we aimed to (1) establish a CAM patient-derived xenograft (PDX) model based on PDOs generated from the liver metastasis of a colorectal cancer (CRC) patient and (2) to evaluate the translational pipeline (patient - in vitro PDOs - in vivo CAM-PDX) regarding morphology, histopathology, expression of C-X-C chemokine receptor type 4 (CXCR4), and radiotracer uptake patterns. Results The main liver metastasis of the CRC patient exhibited high 2-[F-18]FDG uptake and moderate and focal [Ga-68]Ga-Pentixafor accumulation in the peripheral part of the metastasis. Inoculation of PDOs derived from this region onto the CAM resulted in large, highly viable, and extensively vascularised xenografts, as demonstrated immunohistochemically and confirmed by high 2-[F-18]FDG uptake. The xenografts showed striking histomorphological similarity to the patient's liver metastasis. The moderate expression of CXCR4 was maintained in ovo and was concordant with the expression levels of the patient's sample and in vitro PDOs. Following in vitro re-culturing of CAM-PDXs, growth, and [Ga-68]Ga-Pentixafor uptake were unaltered compared to PDOs before transplantation onto the CAM. Although [Ga-68]Ga-Pentixafor was taken up into CAM-PDXs, the uptake in the baseline and blocking group were comparable and there was only a trend towards blocking. Conclusions We successfully established an in vivo CAM-PDX model based on CRC PDOs. The histomorphological features and target protein expression of the original patient's tissue were mirrored in the in vitro PDOs, and particularly in the in vivo CAM-PDXs. The [Ga-68]Ga-Pentixafor uptake patterns were comparable between in v

关键词： CAD-CAM   3D-printed   Dimensional accuracy   Color stability   Thermocycling   Cleanser  

摘要： Background There is a lack of studies comparing the dimensional accuracy and color stability of denture base resins made using computer-aided design and computer-aided manufacturing (CAD-CAM) milling, 3-dimensional (3D) printing, and conventional denture processing techniques. This makes it challenging to determine the best method to fabricate complete dentures. The objective of this in vitro investigation was to assess and contrast the color stability and dimensional accuracy of denture base resins that were 3D printed and CAD-CAM milled, both before and after aging by thermocycling using digital surface matching technology and a benchtop laser scanner without using a spray, to optimize adaptation of the denture base and cast to minimize any imperfections and to evaluate the impact of the denture cleansing solution on the stability of color. Methods Evaluation of the dimensional accuracy (n = 27) was completed on a sectional maxillary stone cast using a digital 3D-surface matching software before and after 5000 thermocycles. A spectrophotometer was used to measure the color change (triangle E00) of all disc specimens (N = 54) before and after 500 thermocycles and immersion in denture cleansing solution for 30 cycles (3 min each) daily for 6 days. The Kruskal Wallis test, Dunn's post hoc test, Tukey's test with Bonferroni adjustment, one sample t test and independent t test were used to statistically analyze the data (alpha < 0.05). Results Thermocycling decreased the dimensional accuracy of the heat polymerized group at all 5 locations and the 3D-printed group at locations 1, 3 and 5 (P > .05), while it had no significant difference on the CAD-CAM milled group at all locations (P < .05). The color change (triangle E00) was lowest in the CAD-CAM milled group, moderate in the heat-polymerized group and highest in the 3D-printed group. After immersion in denture cleanser, the color change (triangle E00) was significantly higher in the 3 groups compared with after ther

关键词： atrial fibrillation   cardiovascular disease   cardiovascular mortality   coronary heart disease   hypertension   obstructive sleep apnea   ACS   acute coronary syndrome   AF   atrial fibrillation   AHI   apnea-hypopnea index   BP   blood pressure   CAD   coronary artery disease   CO 2   carbon dioxide   COPD   chronic obstructive pulmonary disease   CPAP   continuous positive airway pressure   CV   cardiovascular   CVD   cardiovascular disease   EDS   excessive daytime sleepiness   LV   left ventricular   NREM   non–rapid eye movement   OHS   obesity hypoventilation syndrome   OSA   obstructive sleep apnea   PCO 2   partial pressure of carbon dioxide   PFO   patent foramen ovale   PH   pulmonary hypertension   REM   rapid eye movement   SDB   sleep disordered breathing   TNF   tumor necrosis factor  

摘要： AbstractThe American Heart Association considers sleep health an essential component of cardiovascular health, and sleep is generally a time of cardiovascular quiescence , such that any deviation from normal sleep may be associated with adverse cardiovascular consequences. Many studies have shown that both impaired quantity and quality of sleep, particularly with obstructive sleep apnea (OSA) and comorbid sleep disorders, are associated with incident cardiometabolic consequences. OSA is associated with repetitive episodes of altered blood gases, arousals, large negative swings in intrathoracic pressures, and increased sympathetic activity. Recent studies show that OSA is also associated with altered gut microbiota, which could contribute to increased risk of cardiovascular disease. OSA has been associated with hypertension, atrial fibrillation, heart failure, coronary artery disease, stroke, and excess cardiovascular mortality. Association of OSA with chronic obstructive lung disease (overlap syndrome) and morbid obesity (obesity hypoventilation syndrome) increases the odds of mortality.

关键词： CPAP   hypoventilation syndrome   noninvasive ventilation   obesity   OSA   AF   atrial fibrillation   AHI   Apnea-Hypopnea Index   ASV   adaptive servoventilation   BMI   body mass index   BP   blood pressure   CAD   coronary artery disease   CBTi   cognitive behavioral therapy for insomnia   CHF   congestive heart failure   COMISA   obstructive sleep apnea comorbid with insomnia   COPD   chronic obstructive pulmonary disease   CPAP   continuous positive airway pressure   CV   cardiovascular   CVD   cardiovascular disease   DORA   dual-orexin receptor antagonist   FDA   U.S. Food and Drug Administration   HF   heart failure   HFrEF   heart failure with reduced ejection fraction   HNS   hypoglossal nerve stimulation   LG   loop gain   MAD   mandibular advancement device   NIV   noninvasive ventilation   OHS   obesity hypoventilation syndrome   OSA   obstructive sleep apnea   PAH   pulmonary arterial hypertension   PAP   positive airway pressure   PH   pulmonary hypertension   RCT   randomized controlled trial   RV   right ventricular   RYGB   Roux-en-Y gastric bypass   UC   usual care  

摘要： AbstractMany studies have shown an association of obstructive sleep apnea (OSA) with incident cardiovascular diseases, particularly when comorbid with insomnia, excessive sleepiness, obesity hypoventilation syndrome, and chronic obstructive pulmonary disease. Randomized controlled trials (RCTs) have demonstrated that treatment of OSA with positive airway pressure devices (CPAP) improves systemic hypertension, particularly in those with resistant hypertension who are adherent to CPAP. However, large RCTs have not shown long-term benefits of CPAP on hard cardiovascular outcomes, but post hoc analyses of these RCTs have demonstrated improved hard outcomes in those who use CPAP adequately. In theory, low CPAP adherence and patient selection may have contributed to neutral results in intention-to-treat analyses. Only by further research into clinical, translational, and basic underlying mechanisms is major progress likely to continue. This review highlights the various treatment approaches for sleep disorders, particularly OSA comorbid with various other disorders, the potential reasons for null results of RCTs treating OSA with CPAP, and suggested approaches for future trials.

关键词： modified Cam clay model   computational geotechnics   large grid wall   numerical techniques   numerical modelling   ground improvement   deep soil mixing   soft clay  

摘要： Fast Lagrangian analysis of continua (Flac) is a powerful numerical platform for simulating the deformation and stability of geotechnical structures. However, it has been documented that the modified Cam clay (MCC) constitutive model embedded in the Flac platform is deficient at solving geotechnical problems. A new calibration approach by determining the isotropic pre-consolidation pressure (PCP) multiplier based on the relationship between the total stress in the geotechnical problem and the reference pressure is presented in this article. The multiplier was used to establish the nominated maximum isotropic PCP and the maximum referential consolidation ratio at the bottom of the soil layer. Subsequently, the maximum isotropic PCP was used to determine the bulk maximum. In addition, the developed approach was used to investigate the lateral displacement of a large grid wall foundation by deep mixing under adjacent surcharge loading. The feasibility of the approach was validated using centrifuge results. The coefficient of determination (R²) between the lateral displacement obtained from numerical and centrifuge modelling was 0.95. The proposed numerical technique and calibration approach demonstrated that the embedded MCC model can be used to solve practical geotechnical problems.

关键词： CAM   Chronic liver disease  

摘要： BackgroundThe use of Complementary and alternative medicine (CAM) in chronic liver disease (CLD) patients in Germany is unknown. This study investigated the frequency of CAM use and associated sociodemographic, clinical and personality factors in CLD patients in *** is a cross-sectional multicenter study of CLD patients attending liver outpatient clinics of university hospitals in Halle(-Saale) and Homburg between 2015 and 2017. Dedicated questionnaires recorded CAM use, sociodemographic and personality factors (evaluated with the "Big five" model, "Hospital Anxiety and Depression"-, "Multidimensional Health Locus of Control"- score). Uni- and multivariate analyses assessed factors associated to CAM *** 378 patients were recruited, 92 (24.3%) reported to CAM use. On univariate analysis, female CAM users were older (p = 0.001) and more physically active (p = 0.002), male CAM users more often used homeopathy (p = 0.000), actively promoted their health (p = 0.010) or had UDC in their medication (p = 0.004). Logistic regression analysis adjusted for personality factors showed significant association of age, physical exercise (females) and satisfaction with alternative medicine (females, males) to CAM *** use is prevalent among CLD patients in Germany and is significantly associated to satisfaction with alternative medicine (females, males), physical exercise and older age (females). Doctors should actively inquire CLD patients about CAM use, as hepatotoxicity or interaction with medication can occur.

关键词： 3D printing   accuracy   CAD-CAM   finishing   fit   polishing   removable partial denture  

摘要：
Purpose:The purpose of this study was to compare the effects of finishing and polish-ing techniques on the fit accuracy, metal loss, and surface roughness of conventionalversus CAD-CAM removable partial denture (RPD) *** and Methods:A 3D-printed maxillary Kennedy class III modification Imodel served as the master cast. Forty impressions (20 conventional and 20 digi-tal) were divided into four groups: lost-wax technique (Group I: LWT), CAD-printed(Group II: CAD-RP), CAD-printed from a stone cast (Group III: CAD-RPS), and lost-wax technique from resin-printed models (Group IV: LWTR). Various finishing andpolishing techniques were applied, followed by digital scanning for fit accuracy assess-ment using surface matching software. Metal thickness loss and surface roughness wereevaluated pre- and post-finishing and polishing. The Kruskal-Wallis test followed by theScheffe post-hoc test were conducted to evaluate the fit accuracy between groups (alpha=0.05).Results:Color mapping revealed significant differences (p<0.001) between conven-tionally casted RPD frameworks and 3D-printed groups post-finishing and *** most significant gap was observed with the guide plates from printed RPD frame-works. The D-Lyte technique resulted in less metal loss compared to the conventionalfinishing and polishing technique (p<0.001).Conclusion:Within the limitations of this study, conventionally processed RPD groupsexhibited better overall fit accuracy post-finishing and polishing. Both conventional castand 3D-printed RPD frameworks showed clinically acceptable fit accuracy. The D-Lytetechnique presented less metal loss and smoother surfaces compared to other groups,suggesting it as a viable alternative.