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European Journal of Dentistry Jun 2024This study evaluated surface roughness, biaxial flexural strength, and phase transformation of 5Y-PSZ after grinding and polishing with different protocols.
Effect of Grinding and Polishing Protocols on Surface Roughness, Flexural Strength, and Phase Transformation of High-Translucent 5 mol% Yttria-Partially Stabilized Zirconia.
OBJECTIVES
This study evaluated surface roughness, biaxial flexural strength, and phase transformation of 5Y-PSZ after grinding and polishing with different protocols.
MATERIAL AND METHODS
Two commercial 5Y-PSZ, Lava Esthetic (L) and Cercon xt (C), were used and divided into 3 groups: LC and CC represented unpolished control groups; LE and CE were polished with protocol I (EVE DIASYNT® PLUS HP following with EVE DIACERA RA); and LJ and CJ were polished with protocol II (Superfine diamond bur following with Jota ZIR Gloss polishing kit). Surface roughness was evaluated after polishing step-by-step with a contact-type profilometer. After high-gross polishing, the specimens were subjected to biaxial flexural strength test, crystallographic microstructure analysis using an X-ray diffractometer (XRD), and surface micro-topography using scanning electron microscopy (SEM).
STATISTICAL ANALYSIS
Surface roughness differences after each step and biaxial flexural strength between groups were evaluated with one-way ANOVA, followed by Bonferroni post-hoc analysis. Changes in surface roughness across four different time points within groups were assessed using one-way repeated measures ANOVA, followed by Bonferroni post-hoc analysis.
RESULTS
After high-gross polishing, both polishing protocols showed significantly lower surface roughness than the grinding group ( < 0.05). The LE and CE groups exhibited the highest surface roughness values, which were significant differences from the LJ and CJ groups ( < 0.05). The LE group showed significantly lower biaxial flexural strength compared to the LC group ( < 0.05). However, there was no statistically significant difference in the CE and CJ groups compared to the control group ( > 0.05). Furthermore, all polishing protocols did not change the phase transformation of zirconia.
CONCLUSION
Polishing protocol II provided a smoother surface than the protocol I after high-gross polishing, while the biaxial flexural strength of materials remained unaffected.
PubMed: 38942054
DOI: 10.1055/s-0044-1787001 -
European Journal of Dentistry Jun 2024Sintering influences the optical properties of zirconia. This study examined the effect of altering sintering temperature and time of monochrome (Mo) and multilayer...
OBJECTIVES
Sintering influences the optical properties of zirconia. This study examined the effect of altering sintering temperature and time of monochrome (Mo) and multilayer (Mu) 5 mol% yttria-partially stabilized zirconia (5Y-PSZ) on color characteristics.
MATERIALS AND METHODS
Three hundred specimens (width × length × thickness = 10 × 20 × 2 mm) were prepared from Mo and Mu (with cervical [C], middle [M], and incisal [I] region) 5Y-PSZ and randomly sintered at decreasing (Td: 1,450°C), regular (Tr: 1,500°C), and increasing (TI: 1,550°C) sintering temperature, with extremely short (He: 10 minutes), ultrashort (Hu: 15 minutes), short (Hs: 30 minutes), and regular (Hr: 135 minutes) sintering time ( = 15/group). Color appearance ( ), translucency parameter (TP), contrast ratio (CR), opalescence parameter (OP), and color appearance difference (∆ ) were evaluated in the CIE L*a*b* system. Microstructures were evaluated by scanning electron microscope (SEM) and X-ray diffractometer (XRD).
STATISTICAL ANALYSIS
Analysis of variance (ANOVA) and Bonferroni comparisons were determined for significant differences ( < 0.05).
RESULTS
Significant differences in color parameters upon zirconia type, sintering temperature, and sintering time, and their interactions were indicated ( < 0.05). Increasing sintering temperature and extended sintered time resulted in larger grain, reduced tetragonal-to-monoclinic phase transformation, and significantly increased the TP and OP, but decreased the CR and ∆ ( < 0.05). Decreasing sintering temperature and time led to clinically unacceptable color appearance.
CONCLUSION
Mo was found to be more translucent than Mu. To achieve the most favorable optical properties, increasing sintering temperature and extending sintering time are recommended. Decreasing sintering temperature is not suggested. However, shortened sintering time is feasible, but it needs sintering with increasing sintering temperature to achieve a promising color appearance.
PubMed: 38942053
DOI: 10.1055/s-0044-1787700 -
European Journal of Dentistry Jun 2024This study aims to investigate DSM 17938's antibiofilm effects on and , common causes of alveolar osteitis. It seeks topical alternatives to prevent this condition...
OBJECTIVES
This study aims to investigate DSM 17938's antibiofilm effects on and , common causes of alveolar osteitis. It seeks topical alternatives to prevent this condition posttooth extraction. The secondary objective is to assess these effects under different pH conditions (pH 4.5 and pH 7), mimicking oral cavity saliva pH dynamics.
MATERIALS AND METHODS
Ethical approval was secured for the saliva collection process involving five healthy adult participants who had undergone wisdom tooth extraction. Saliva samples were diligently collected on the 7th day post-surgery. The unstimulated saliva underwent a series of treatments, including the addition of phenylmethylsulfonyl fluoride (PMSF), pH adjustments, centrifugation, and filtration. The pH levels were re-measured, and subsequent adjustments were made to achieve pH values of 4.5 or 7. DSM 17938, with a concentration of 1×10 colony-forming units (CFU) per 5 drops, was utilized in the study. Biofilm testing involved incubating saliva samples with varying pH (4.5 or 7) alongside bacterial suspensions (, or a mixed species). The Interlac suspension was introduced, and plates were anaerobically incubated for 24 hours. Biofilm results were obtained using a spectrometer. The test is conducted in triplicate.
STATISTICAL ANALYSIS
To scrutinize the impact of pH on biofilm development, the acquired data underwent a two-way ANOVA test in SPSS as part of the statistical analysis. A significance level of <0.05 was used to determine statistical significance.
RESULTS
DSM 17938 significantly reduced biofilm formation across bacterial strains ( = 0.000). Statistical analysis indicated a significant impact of pH on biofilm development ( = 0.000) compared to no saliva samples, with higher formation observed under acidic conditions (pH 4.5). However, the pH levels of 4.5 and 7 did not result in significantly different bacterial biofilm formation ( = 0.529).
CONCLUSION
This research highlights DSM 17938's potency in inhibiting biofilm formation of and . Salivary pH variations significantly influence biofilm development, emphasizing the need to consider pH when assessing probiotic effectiveness. Despite limitations in saliva sample sterilization, this study provides valuable insights into alternative approaches for preventing alveolar osteitis. Further research should explore clinical applications and refine sterilization methods for more accurate results.
PubMed: 38942052
DOI: 10.1055/s-0044-1786846 -
Journal of Photochemistry and... Jun 2024Phototherapy has been extensively used to prevent and treat signs of aging and stimulate wound healing, and phototherapy through light-emitting diodes (LEDs). In...
Phototherapy has been extensively used to prevent and treat signs of aging and stimulate wound healing, and phototherapy through light-emitting diodes (LEDs). In contrast to LED, organic LED (OLED) devices are composed of organic semiconductors that possess novel characteristics. We investigated the regenerative potential of OLED for restoring cellular potential from senescence and thus delaying animal aging. Bone marrow-derived stem cells (BMSCs) and adipose-derived stem cells (ADSCs) were isolated from the control and OLED- treated groups to evaluate their proliferation, migration, and differentiation potentials. Cellular senescence was evaluated using a senescence-associated β-galactosidase (SA-β-gal) activity assay and gene expression biomarker assessment. OLED treatment significantly increased the cell proliferation, colony formation, and migration abilities of stem cells. SA-β-gal activity was significantly decreased in both ADSCs and BMSCs in the OLED-treated group. Gene expression biomarkers from treated mice indicated a significant upregulation of IGF-1 (insulin growthfactor-1). The upregulation of the SIRT1 gene inhibited the p16 and p19 genes then to downregulate the p53 expressions for regeneration of stem cells in the OLED-treated group. Our findings indicated that the survival rates of 10-month aging senescence-accelerated mouse prone 8 mice were prolonged and that their gross appearance improved markedly after OLED treatment. Histological analysis of skin and brain tissue also indicated significantly greater collagen fibers density, which prevents ocular abnormalities and β-amyloid accumulation. Lordokyphosis and bone characteristics were observed to resemble those of younger mice after OLED treatment. In conclusion, OLED therapy reduced the signs of aging and enhanced stem-cell senescence recovery and then could be used for tissue regeneration.
PubMed: 38941921
DOI: 10.1016/j.jphotobiol.2024.112957 -
Journal of the Mechanical Behavior of... Jun 2024Tooth extraction is a common clinical procedure with biomechanical factors that can directly influence patient outcomes. Recent development in atraumatic extraction...
BACKGROUND AND OBJECTIVE
Tooth extraction is a common clinical procedure with biomechanical factors that can directly influence patient outcomes. Recent development in atraumatic extraction techniques have endeavoured to improve treatment outcomes, but the characterization of extraction biomechanics is sparse. An axisymmetric inverse finite element (FE) approach is presented to represent the biomechanics of vertical atraumatic tooth extraction in an ex-vivo swine model.
METHODS
Geometry and boundary conditions from the model are determined to match the extraction of swine incisors in a self-aligning ex vivo extraction experiment. Material parameters for the periodontal ligament (PDL) model are determined by solving an inverse FE problem using clusters of data obtained from 10 highly-controlled mechanical experiments. A seven-parameter visco-hyperelastic damage model, based on an Arruda-Boyce framework, is used for curve fitting. Three loading schemes were fit to obtain a common set of material parameters.
RESULTS
The inverse FE results demonstrate good predictions for overall force-time curve shape, peak force, and time to peak force. The fit model parameters are sufficiently consistent across all three cases that a coefficient-averaged model was taken that compares well to all three cases. Notably, the initial modulus ,u, converged across trials to an average value of 0.472 MPa with an average viscoelastic constant g of 0.561.
CONCLUSIONS
The presented model is found to have consistent parameters across loading cases. The capability of this model to represent the fundamental mechanical characteristics of the dental complex during vertical extraction loading is a significant advancement in the modelling of extraction procedures. Future work will focus on verifying the model as a predictive design tool for assessing new loading schemes in addition to investigating its applications to subject-specific problems.
PubMed: 38941913
DOI: 10.1016/j.jmbbm.2024.106641 -
Hearing Research Jun 2024Following adult-onset hearing impairment, crossmodal plasticity can occur within various sensory cortices, often characterized by increased neural responses to visual...
Following adult-onset hearing impairment, crossmodal plasticity can occur within various sensory cortices, often characterized by increased neural responses to visual stimulation in not only the auditory cortex, but also in the visual and audiovisual cortices. In the present study, we used an established model of loud noise exposure in rats to examine, for the first time, whether the crossmodal plasticity in the audiovisual cortex that occurs following a relatively mild degree of hearing loss emerges solely from altered intracortical processing or if thalamocortical changes also contribute to the crossmodal effects. Using a combination of an established pharmacological 'cortical silencing' protocol and current source density analysis of the laminar activity recorded across the layers of the audiovisual cortex (i.e., the lateral extrastriate visual cortex, V2L), we observed layer-specific changes post-silencing in the strength of the residual visual, but not auditory, input in the noise exposed rats with mild hearing loss compared to rats with normal hearing. Furthermore, based on a comparison of the laminar profiles pre- versus post-silencing in both groups, we can conclude that noise exposure caused a re-allocation of the strength of visual inputs across the layers of the V2L cortex, including enhanced visual-evoked activity in the granular layer; findings consistent with thalamocortical plasticity. Finally, we confirmed that audiovisual integration within the V2L cortex depends on intact processing within intracortical circuits, and that this form of multisensory processing is vulnerable to disruption by noise-induced hearing loss. Ultimately, the present study furthers our understanding of the contribution of intracortical and thalamocortical processing to crossmodal plasticity as well as to audiovisual integration under both normal and mildly-impaired hearing conditions.
PubMed: 38941694
DOI: 10.1016/j.heares.2024.109071 -
Medicine Jun 2024Healthy eating and weight control are recommended for cancer survivors; however, dietary interventions are not routinely offered to them. This study aimed to assess the... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Healthy eating and weight control are recommended for cancer survivors; however, dietary interventions are not routinely offered to them. This study aimed to assess the effects of dietary interventions on survival, nutritional status, morbidity, dietary changes, health-related quality of life (QOL), and clinical measures in cancer survivors.
METHODS
Searches were conducted from October 1, 2018 to November 21, 2011 in the Medline, EMBASE, CENTRAL, Emcare, and DARE electronic databases. We included randomized controlled trials (RCTs) that involved individuals diagnosed with cancer, excluding conference abstracts, case studies, other reviews, and meta-analyses, and screened the articles.
RESULTS
Eight studies were included in this meta-analysis. We observed significant improvements in QOL and clinical data in 3 of 6 studies and in one study, respectively, significant weight loss on anthropometry in 2 of 5 studies, and dietary improvement in 4 of 5 studies of adult cancer survivors. However, we did not observe any benefits of dietary intervention for cancer survivors with undernutrition.
DISCUSSION
Dietary interventions for adult cancer survivors might contribute to improving their nutritional status; however, further clarification requires a study that standardizes the intervention method. Furthermore, RCTs are required to determine the effects on cancer survivors with undernutrition.
Topics: Adult; Humans; Cancer Survivors; Neoplasms; Nutritional Status; Quality of Life; Randomized Controlled Trials as Topic
PubMed: 38941414
DOI: 10.1097/MD.0000000000038675 -
PloS One 2024Evidence from in vitro and animal models has identified the pulmonary toxicity of flavors in electronic cigarettes (ECIGs); however, less is known from epidemiological...
Evidence from in vitro and animal models has identified the pulmonary toxicity of flavors in electronic cigarettes (ECIGs); however, less is known from epidemiological studies about the effects of flavors in the respiratory health. This study examined the longitudinal association between exposure to ECIGs flavors and nocturnal dry cough among ECIGs users. A secondary analysis of data from the Population Assessment of Tobacco and Health Study (2014-2019) was conducted. The study population included adults who provided information (n = 18,925) for a total of 38,638 observations. Weighted-incidence estimates and weighted- generalized estimating equation models were performed to assess unadjusted and adjusted associations. The weighted incidence proportion (WIP) of nocturnal dry cough was significantly higher among current (WIP:16.6%; 95%CI 10.5, 21.2) and former fruit flavored ECIGs users (WIP:16.6%; 95%CI 11.3, 21.9) as compared to non-ECIGs users (WIP:11.1%; 95%CI 10.6, 11.6). Current ECIGs users of fruit flavors showed 40% higher risk of reporting cough than non-ECIGs users (aRR:1.40, 95%CI 1.01, 1.94). Former ECIGs users of multiple flavors and other flavors had 300% and 66% higher risk to develop cough, respectively (aRR:3.33, 95%CI 1.51, 7.34 and aRR:1.66, 95%CI 1.0.9, 2.51), relative to non-ECIGs users. We observed a significantly higher risk of developing nocturnal dry cough in the past 12 months in current and former ECIGs users of fruit flavors and in former ECIGs users of multiple flavors. To the extent that cough may serve as an early indicator of respiratory inflammation and potential disease risk, the association between ECIGs use and cough raises potential concerns.
Topics: Humans; Electronic Nicotine Delivery Systems; Cough; Female; Male; Adult; Middle Aged; Longitudinal Studies; Fruit; Flavoring Agents; Aged; Young Adult; Incidence
PubMed: 38941336
DOI: 10.1371/journal.pone.0306467 -
PloS One 2024Many newborn screening programs worldwide have introduced screening for diseases using DNA extracted from dried blood spots (DBS). In Germany, DNA-based assays are...
BACKGROUND
Many newborn screening programs worldwide have introduced screening for diseases using DNA extracted from dried blood spots (DBS). In Germany, DNA-based assays are currently used to screen for severe combined immunodeficiency (SCID), spinal muscular atrophy (SMA), and sickle cell disease (SCD).
METHODS
This study analysed the impact of pre-analytic DNA carry-over in sample preparation on the outcome of DNA-based newborn screening for SCID and SMA and compared the efficacy of rapid extraction versus automated protocols. Additionally, the distribution of T cell receptor excision circles (TREC) on DBS cards, commonly used for routine newborn screening, was determined.
RESULTS
Contaminations from the punching procedure were detected in the SCID and SMA assays in all experimental setups tested. However, a careful evaluation of a cut-off allowed for a clear separation of true positive polymerase chain reaction (PCR) amplifications. Our rapid in-house extraction protocol produced similar amounts compared to automated commercial systems. Therefore, it can be used for reliable DNA-based screening. Additionally, the amount of extracted DNA significantly differs depending on the location of punching within a DBS.
CONCLUSIONS
Newborn screening for SMA and SCID can be performed reliably. It is crucial to ensure that affected newborns are not overlooked. Therefore a carefully consideration of potential contaminating factors and the definition of appropriate cut-offs to minimise the risk of false results are of special concern. It is also important to note that the location of punching plays a pivotal role, and therefore an exact quantification of TREC numbers per μl may not be reliable and should therefore be avoided.
Topics: Humans; Neonatal Screening; Infant, Newborn; Muscular Atrophy, Spinal; Severe Combined Immunodeficiency; DNA; Dried Blood Spot Testing; High-Throughput Screening Assays; Polymerase Chain Reaction
PubMed: 38941330
DOI: 10.1371/journal.pone.0306329 -
Oncology and Therapy Jun 2024Breast cancer presents diverse molecular subtypes affecting treatment strategies. Human epidermal growth factor receptor 2 (HER2)-low, hormone receptor-positive (HR+)...
BACKGROUND
Breast cancer presents diverse molecular subtypes affecting treatment strategies. Human epidermal growth factor receptor 2 (HER2)-low, hormone receptor-positive (HR+) breast cancer poses a challenge due to limited targeted therapies. Current neoadjuvant treatment primarily utilizes chemotherapy, with conflicting results regarding efficacy in patients with HER2-low breast cancer. Trastuzumab deruxtecan (T-DXd) shows promise in HER2-low metastatic disease, and preliminary evidence suggests synergy with endocrine therapy.
OBJECTIVE
This editorial explores the hypothesis that neoadjuvant T-DXd with or without endocrine therapy offers efficacy in the clinical management of HR+/HER2-low breast cancer.
METHODS
We propose a phase II study with two treatment arms: T-DXd + letrozole and T-DXd alone. The primary endpoint is the radiological complete response rate. Secondary endpoints include pathological complete response rate, safety, event-free survival, and overall survival. Exploratory analyses will compare the arms to identify potential for optimizing treatment efficacy and minimizing side effects.
CONCLUSIONS
This study design allows for initial assessment of T-DXd with or without endocrine therapy in the treatment of HER2-low breast cancer. The findings may pave the way for personalized treatment strategies and inform future research, potentially leading to a chemotherapy-sparing approach.
PubMed: 38941050
DOI: 10.1007/s40487-024-00286-3