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关键词： resin-bonded   finite element analysis   dental prosthesis design   dental stress analysis   anterior tooth loss  

摘要： Background Computer-aided design/manufacturing (CAD/CAM) materials are widely used in resin-bonded fixed partial dentures (RBFPDs), but their suitability across different designs has not been fully assessed. This study compares the stress distribution and failure probability of mandibular incisors restored by RBFPDs with various CAD/CAM *** and methods Finite-element models of single- and double-ended RBFPDs were created using cone-beam computed tomography (CBCT) data. Five CAD/CAM materials (IPS *** CAD, IPS *** ZirCAD, Vita Enamic, Lava Ultimate, Vitablocs MarkII) were tested under vertical and oblique (45 degrees) loading with a 100 N force. Stress distribution and failure risk were evaluated for each material and *** Oblique loading produced the highest stress and displacement for single-ended RBFPDs. Lava Ultimate had the largest displacement and principal stress, while IPS *** ZirCAD showed the highest equivalent stress. IPS *** CAD exhibited the lowest displacement and principal stress among double-ended RBFPDs under oblique *** This study demonstrated that double-ended RBFPDs experience lower stress and strain compared to single-ended designs, particularly under oblique loading. Vita Enamic had the highest failure risk, while IPS *** ZirCAD had the lowest. These insights into stress distribution and material performance offer valuable guidance for material selection and restoration design, aiming to improve the longevity and success of RBFPDs in mandibular incisor restorations.

关键词： Angiogenesis   Avian animal model   Bone regeneration   Chitosan   Polyhydroxybutyrate  

摘要： In recent years, the chorioallantoic membrane (CAM) has emerged as a crucial component of biocompatibility testing for biomaterials designed for regenerative strategies and tissue engineering applications. This study explores angiogenic potential of an innovative acellular and porous biopolymer scaffold, based on polyhydroxybutyrate and chitosan (PHB/CHIT), using the ex ovo quail CAM assay as an alternative to the conventional chick CAM test. On embryonic day 6 (ED6), we placed the tested biomaterials on the CAM alone or soaked them with various substances, including vascular endothelial growth factor (VEGF-A), saline, or the endogenous angiogenesis inhibitor Angiostatin. After 72 h (ED9), we analyzed blood vessels formation, a sign of ongoing angiogenesis, in the vicinity of the scaffold and within its pores. We employed marker for cell proliferation (PHH3), embryonic endothelium (WGA, SNA), myofibroblasts (alpha-SMA), and endothelial cells (QH1) for morphological and histochemical analysis. Our findings demonstrated the robust angiogenic potential of the untreated scaffold without additional influence from the angiogenic factor VEGF-A. Furthermore, gene expression analysis revealed an upregulation of pro-angiogenic growth factors, including VEGF-A, ANG-2, and VE-Cadherin after 5 days of implantation, indicative of a pro-angiogenic microenvironment. These results underscore the inherent angiogenic potential of the PHB/CHIT composite. Additionally, monitoring of CAM microvilli growing to the scaffold provides a methodology for investigating the biocompatibility of materials using the ex ovo quail CAM assay as a suitable alternative model compared to the chicken CAM platform. This approach offers a rapid screening method for biomaterials in the field of tissue repair/regeneration and engineering.

关键词： OHCA   coronary angiography   myocardial infarction   NSTE   CAD  

摘要： Background: Early coronary angiography (CAG) in post-cardiac arrest patients without ST-segment elevation is a topic of debate. This meta-analysis aimed to assess its impact on outcomes. Methods: A search of Medline and Cochrane up to February 2023 was conducted to identify randomized controlled trials and observational studies comparing patients undergoing early CAG vs. delayed/no CAG after experiencing out-of-hospital cardiac arrest. A random-effects model pooled odds ratios (ORs) with 95% confidence intervals (CIs). Meta-regression explored factors modifying effect sizes. Results: We identified 16 studies (7 RCTs, 9 observational studies) involving 4,737 patients. Early CAG significantly reduced long-term mortality [OR: 0.66 (0.51-0.85)], and increased favorable cerebral performance category (CPC) 1-2 at discharge [OR: 1.49 (1.09-2.03)]. Observational study subgroup showed decreased short-term mortality, long-term mortality, and CPC 1-2 at discharge, unlike RCT subgroup. Meta-regression revealed type 2 diabetes mellitus and follow-up time influencing short-term mortality and CPC 1-2 at discharge, respectively. Conclusion: Early CAG in post-cardiac arrest patients without ST elevation is associated with long-term clinical benefits, particularly evident in observational studies. Interpretation should be cautious.

关键词： biaxial flexural strength   CAD-CAM   thermal cycling   three-dimensional printing   Vickers hardness  

摘要： Purpose: To compare the strength, surface roughness, and hardness of newly introduced permanent three-dimensional (3D)-printed resin in comparison with computer-aided design and computer-aided manufacturing (CAD-CAM) milled materials. Materials and methods: Three 3D-printed resins (NextDent C&B, Formlabs Permanent Crown, and VarseoSmile Crown plus) and two CAD-CAM milled (IPS *** ZirCAD LT and VITA Enamic) resins were used to fabricate discs specimens. A total of 200 disc specimens were fabricated according to manufacturer recommendations. Within each group, half of the specimens were subjected to thermal cycling (5 degrees C-55 degrees C, the 30 s, 5000 cycles). Aged and nonaged specimens were evaluated for biaxial flexural strength (BFS), surface roughness, and hardness. Results were statistically analyzed using analysis of variance (ANOVA) and t-tests (alpha = 0.05). Results: Significant differences (p < 0.05) were observed in the BFS, surface roughness, and hardness between the 3D-printed and milled groups, before and after thermal aging. Overall, the CAD-CAM milled ceramic group had superior strength, surface roughness, and hardness when compared to all other groups (p < 0.001), except for surface roughness after thermal aging, which was similar in all groups (p = 0.063). Within each group, there was no significant difference (p > 0.05) in surface roughness after thermal aging. BFS values of 3D-printed materials were statistically similar. In terms of surface roughness, Formlabs specimens displayed the highest value before and after thermal cycling, when compared to other 3D-printed materials. Regarding hardness, the VarseoSmile Crown plus group demonstrated the highest values compared to other 3D-printed materials, before and after thermal cycling. Conclusion: Permanent 3D-printed resins have lower strength than CAD-CAM milled materials. 3D-printed permanent resin materials exhibited high roughness and comparable hardness to CAD-CAM materials. Thermal aging

关键词： ISM: lines and bands   galaxies: evolution   galaxies: high-redshift   galaxies: luminosity function, mass function   galaxies: star formation   galaxies: statistics   galaxies: statistics  

摘要： Context. The Fred Young Submillimeter Telescope (FYST) line intensity mapping (LIM) survey will measure the power spectrum (PS) of the singly ionized carbon 158 mu m fine-structure line, [CII], to trace the appearance of the first galaxies that emerged during and right after the epoch of reionization (EoR, 6 < z < 9). Aims. We aim to quantify the contamination of the (post-)EoR [CII] LIM signal by foreground carbon monoxide (CO) line emission (3 < J(up) < 12) and assess the efficiency to retrieve this [CII] LIM signal by the targeted masking of bright CO emitters. Methods. Using the IllustrisTNG300 simulation, we produced mock CO intensity tomographies based on empirical star formation rate-to-CO luminosity relations. Combining these predictions with the [CII] PS predictions of the first paper of this series, we evaluated a masking technique where the interlopers are identified and masked using an external catalog whose properties are equivalent to those of a deep Euclid survey. Results. Prior to masking, our [CII] PS forecast is an order of magnitude lower than the predicted CO contamination in the 225 GHz ([CII] emitted at z = 6.8 - 8.3) band of the FYST LIM survey, at the same level in its 280 GHz ([CII] emitted at z = 5.3 - 6.3) and 350 GHz ([CII] emitted at z = 4.1 - 4.8) bands, and an order of magnitude higher in its 410 GHz ([CII] emitted at z = 3.4 - 3.9) band. For our fiducial model, the optimal masking depth is reached when less than 10% of the survey volume is masked at 350 and 410 GHz but around 40% at 280 GHz and 60% at 225 GHz. At these masking depths we anticipate a detection of the [CII] PS at 350 and 410 GHz, a tentative detection at 280 GHz, whereas at 225 GHz the CO signal still dominates our model. In the last case, alternative decontamination techniques will be needed.

关键词： Adhesion   CAD/CAM composite   dental materials   resin cement   resin composite   dentin bond strength   Vickers hardness   ultimate tensile strength  

摘要： To correlate mu TBS of different resin cements with their film thickness (FT), Vickers hardness (HV), and ultimate tensile strength (UTS). Human molars (N = 30) were divided into six-groups according to 1: Resin cement: Bifix QM, (BF), GrandioSo Heavy Flow (GHF) and VisCalor Bulk (VB), and 2: Adhesive mode (Optibond Universal): Etch-and-rinse (E&R) or self-etching (SE). CAD/CAM blocks (7 x 7 x 4 mm(3)) were air-abraded using 50 mu m Al2O3 and silane was applied (60 s), and air dried (10 s). For E&R, dentin was etched (15 s), rinsed (30 s), and blot-dried. For both modes, adhesive was applied (20 s), air-dried (5 s), and photo-polymerized (10 s). Sticks (1 x 1 mm(2)) were stored for 24-h or 6-months. Sticks were pulled in tension (1 mm/min). Debonded sticks were evaluated for failure mode analysis. For FT, nine-bonded slabs from each cement was prepared and evaluated. For UTS, eight-hourglass specimens from each cement were prepared and tested in tension. For HV, five-discs from each cement was prepared and evaluated using a HV tester. Data were analyzed using ANOVA/Pearson's correlation tests (alpha = 0.05). No correlation between mu TBS/HV was revealed (p > 0.05). A positive correlation between mu TBS/FT and mu TBS/UTS (p < 0.05) was observed. Three-way ANOVA revealed all experimental factors had a significant effect on TBS (p < 0.05). The VB showed significantly lower TBS (20.8 +/- 9.3 MPa). The E&R mode showed higher mu TBS (26.0 +/- 10.9 MPa), and 24-h revealed a higher mu TBS (27.4 +/- 10.0 MPa). Mixed failure was the predominant type (42.51%). The VB showed the highest FT (122.2 +/- 11.9 mu m), with GHF revealed higher UTS and HV (112.5 +/- 19.7 MPa and 91.6 +/- 0.4 Kgf, respectively). Photo-polymerized flowable composite can substitute dual-polymerized cement for CAD/CAM composite bonding.

关键词： Hybrid ceramic   Lithium disilicate ceramic   gastric juice   Orthodontic bracket   Shear bond strength   Surface treatment  

摘要： To evaluate the shear bond strength (SBS) of ceramic and metallic orthodontic brackets bonded to lithium disilicate ceramics or hybrid ceramics and subjected to different surface conditioning treatments.

关键词： CAD-CAM block   Degree of conversion   Flowable resin composite   Luting material   Translucency  

摘要： Aim This in-vitro study aimed to evaluate the degree of conversion (DC) of dual-cured luting cement (Bifix QM, VOCO) and flowable composite (Grandio Flow, VOCO) under lithium disilicate glass-ceramic (IPS *** CAD, Ivoclar Vivadent) and hybrid ceramic (Grandio Blocs, VOCO;Cerasmart, GC) CAD-CAM blocks with different thicknesses. Materials and methods Contrast ratio (CR), translucency (TPab, TP00), and opalescence (OP) parameters of 30 disc-shaped CAD-CAM blocks (n = 5) prepared with two different thicknesses (1.5 and 2 mm) and 8 mm diameters were calculated using a spectrophotometer (VITA Easyshade V, Zahnfabrik). A total of 36 Bifix QM and Grandio Flow samples were prepared at 100 mu m thickness using a specific setup by polymerizing from the top of the blocks. Following immersion in distilled water at 37 degrees C for 24 h, luting materials were examined by Fourier Transform Infrared Spectroscopy for DC calculation. Data were analyzed using One-way ANOVA, Kruskal Wallis, Mann Whitney U, and Independent Samples t-tests (p < 0.05). Results It was observed that, as the block thickness increased TPab, TP00, and OP decreased, while CR increased. There was no significant difference between the DC of Bifix QM and Grandio Flow when 1.5 mm blocks were used in all groups (p > 0.05). DC of Grandio Flow was significantly higher than Bifix QM under 2 mm-IPS *** CAD (p = 0.011). Conclusion The translucency of the CAD-CAM blocks varies depending on their thickness. However, there was no significant difference in the DC of the luting materials depending on the block thickness. Further studies are needed on the use of flowable resin composites as luting material.

关键词： Drug-coated balloon   Drug-eluting stent   Complex coronary artery disease   ACS   acute coronary syndrome   BARC   Bleeding Academic Research Consortium   CAD   coronary artery disease   CCS   chronic coronary syndrome   CTO   chronic total occlusion   DAPT   dual antiplatelet therapy   DCB   drug-coated balloon   DES   drug-eluting stent   HBR   high bleeding risk   ISR   in-stent restenosis   IVUS   intravascular ultrasound   MACE   major adverse cardiac events   MI   myocardial infarction   NACE   net adverse cardiovascular events   OCT   optical coherence tomography   PCI   percutaneous coronary intervention   SCB   sirolimus-coated balloon   TLR   target lesion revascularization  

摘要： AbstractIntroductionPercutaneous coronary intervention (PCI) with drug-eluting stents (DES) in complex coronary artery disease (CAD) has been established as the standard of care, but stent-related events are not uncommon. Sirolimus-Coated Balloon (SCB)-based angioplasty is an emerging technology, although it needs to be thoroughly evaluated compared with DES in the complex PCI setting. This study aimed to investigate the safety and efficacy of SCB-based angioplasty compared with new-generation DES in complex PCI. MethodsNet adverse cardiovascular events (NACE: all-cause death, target lesion revascularization, non-fatal myocardial infarction, and major bleedings according to BARC classification), as a primary study endpoint was compared between SCB and new-generation DES for complex coronary lesions. ResultsAmong 1782 patients with complex CAD, 1076 were treated with a sirolimus-coated balloon (EASTBOURNE Registry) and 706 with new-generation DES (COMPLEX Registry). After propensity score matching, a total of 512 patients in both groups were analyzed. NACE occurred more significantly in the DES group during the 1-year follow-up (10.5% vs. 3.9%, p = 0.003), mainly due to a higher risk of bleeding (6.6% vs. 0.4%, p = 0.001). The Cox model adjusted for lesion length showed a significantly lower hazard of NACE (HR: 0.23, CI [0.10, 0.52], p < 0.001) and all-cause mortality (HR: 0.07, CI [0.01, 0.66], p = 0.020) in SCB compared to DES group. ConclusionsSCB angioplasty has an advantage over DES for the treatment of complex CAD regarding NACE, significantly reducing the incidence of major bleeding without increasing ischemic endpoints. SCB may be an alternative to DES in selected patients with complex coronary lesions.