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1.
Healthcare (Basel) ; 12(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38727440

ABSTRACT

Oral health is situated within the framework of the global health agenda, addressing facets pertaining to well-being and quality of life. The research is based on the need to address variables at the community level to improve schoolchildren's oral health and promote healthy behaviors and aims to carry out an in-depth analysis from the perspective of the factors that influence children's oral health. Step 1, designed by the World Health Organization, was utilized. An easy-to-use web interface was created for data collection. The statistical analysis consisted of using multinomial and binominal logistic regression models. The level of education of the adult has a high probability of influencing the consumption of unhealthy or healthy foods, it has a significant probability of exerting influence on social or medical problems and a correlation was found between the level of academic education and the pattern of dental visits. The development of health-promoting behaviors begins in childhood and involves parents, who have an essential role in the education of their children. Oral health promotion programs in schools need to target the child-adult-teacher-dentist relationships. Taking into consideration the aforementioned, a threefold viewpoint is necessary for the development of a national program aimed at promoting the oral health of schoolchildren in Romania.

2.
Healthcare (Basel) ; 12(2)2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38255086

ABSTRACT

This research analyzes the dental hygiene habits of schoolchildren from parents' perspectives, using the STEPS approach recommended by the World Health Organization. The key points of oral health care in children include the role of the family in encouraging and maintaining proper oral hygiene practices. This study aimed to assess the oral hygiene practices of schoolchildren with on-site dentists in Romania. Additionally, it sought to establish correlations between these behaviors and the educational levels of the adults with whom they live with. The participants were selected from the zero grade to the eighth grade, totaling 3843students. Statistical analysis involved the application of Fisher's Exact Test and Z-tests with Bonferroni correction. Multinominal and binominal logistic regression models were employed to predict the impact of parents' education on children's oral health status and behavior. The oral health status of children evaluated by parents as poor was more frequent in children whose parents had a primary or gymnasium education (p < 0.001). Female adults with a university education evaluated the gum health of their children as very good to a much greater extent (41.7%, p < 0.001). Regarding the use of auxiliary means, the majority of parents with a university education mentioned that their children use dental floss (26.4% females/27.4% males) (p < 0.001), compared to those with primary education, where the percentage was only (1.2% males/3.5% females) (p < 0.001). The results of this study highlight that the education level of the adults with whom the children live with influences the perception of the teeth and gums health status, the frequency of oral hygiene, the use of fluoride toothpaste, and auxiliary brushing aids.

3.
J Clin Med ; 11(15)2022 Jul 27.
Article in English | MEDLINE | ID: mdl-35893440

ABSTRACT

A great burden is put on healthcare systems by dental caries and understanding patients' treatment needs is of utmost importance. The aim of this pre−post study was to assess dental anxiety and the psychological stress induced by two different types of dental treatment (prophylaxis and cavity preparation), by combining psychometric evaluations with salivary biomarkers, in a group of 28 schoolchildren presenting in a university clinic. Pre- and post-treatment unstimulated whole saliva was collected and levels of cortisol, alpha-amylase (sAA) and total protein content were measured. The State−Trait Anxiety Inventory for Children and the Frankl Behaviour Rating Scale (FBRS) were applied. Statistical analysis was performed using the Stata/IC 16 (StataCorp) programme. All salivary parameters showed strong positive correlations between pre- and post-treatment levels. Post-treatment, salivary cortisol decreased (p = 0.008, paired t-test), sAA did not change significantly (p = 0.572, sign test), while the sAA/cortisol ratio (AOC) increased (p = 0.036, sign test). There were no correlations between state and trait anxiety levels. State anxiety scores registered significantly higher values for children with an FBRS score of 3 compared with a score of 4 (p < 0.001, unpaired t-test). The post-treatment decrease in the salivary cortisol level was higher for prophylaxis compared with the cavity preparation group (p = 0.024, t-test). These results demonstrate that sAA and cortisol levels are altered differently by psychological stress induced by two different types of dental treatment.

4.
Children (Basel) ; 9(3)2022 Mar 02.
Article in English | MEDLINE | ID: mdl-35327715

ABSTRACT

Salivary biomolecules are considered important modulators of the oral microflora, with a potential subsequent impact on dental health. The present study aimed to investigate the relationship between salivary enzymatic activity and carious experience in children. The carious experience of a sample of 22 school children was evaluated by calculating dmf/DMF indices, following WHO recommendations. Unstimulated whole saliva was collected, and salivary alpha-amylase levels, total protease activity, and matrix metalloproteinase levels (MMP-8 and MMP-9) were measured. The data were analyzed using parametric and nonparametric tests. Our findings revealed no significant relationship between the investigated salivary parameters and the carious experience in permanent teeth (DMFT/DMFS scores). Carious indices scores for primary teeth (dmft and dmfs) were positively associated with MMP-8 levels (r = 0.62, p = 0.004 and rs = 0.61, p = 0.006, respectively) and MMP-9 levels (r = 0.45, p = 0.05 and rs = 0.48, p = 0.039, respectively) and negatively associated with alpha-amylase levels (rs = -0.54, p = 0.017 and rs = -0.59, p = 0.006, respectively). Although with a marginal significance, PEK-054 levels positively correlated with dental caries, while for PFU-089, a negative correlation was observed. These results suggest that salivary alpha-amylase and MMP-8 and MMP-9 levels may be considered potential indicators of carious experience in children. Further studies with a prospective design are needed in order to elucidate the role of these biomolecules in caries development.

5.
Rom J Morphol Embryol ; 62(1): 53-62, 2021.
Article in English | MEDLINE | ID: mdl-34609408

ABSTRACT

INTRODUCTION: Dental agenesis (DA), brings together the anodontia, oligodontia, hypodontia, characterized by a deficit in the development of a variable number of teeth. The objectives of the study were to illustrate the phenotypic variability of non-syndromic DA, to identify cases of DA with hereditary genetic transmission, and establish the mode of DA genetic pattern in these cases, together with the determination of DA prevalence in the population group study. PATIENTS, MATERIALS AND METHODS: The cross-sectional observational study was performed on a mixed population group, consisting of 861 Caucasian patients, between January 2018-December 2019. The clinical evaluation protocol of patients with DA, used to illustrate their phenotype, included the following stages: oral examination, photographic examination, and radiological examination. The evaluation protocol specific to the family genetic study of patients with DA, involved the following three stages: family survey, construction of the family tree and analysis of the pedigree structure. RESULTS: The prevalence of DA in the population group was 2.78%. Regarding the phenotype, DA mainly affected the upper arch (50% of cases); bilateral DA had a significantly increased incidence (83.33% of cases) compared to unilateral form; in most cases (75%), a patient lacked one to two teeth, the lack of two teeth being the most common form (83.33% of cases); the upper lateral incisors were the teeth most frequently involved in DA (31.11% of the total missing teeth). Regarding the family genetic study, hereditary DA with autosomal dominant inheritance was present in 37.50% of cases. In the other cases (62.50%), isolated, sporadic forms of DA were registered, suggesting a spontaneous de novo mutation or a disorder of odontogenesis of a non-genetic nature. CONCLUSIONS: We consider that this study is of interest for current scientific research with applicability in dental medicine, by bringing actual information on the prevalence of non-syndromic DA in South-East Romania, the variety of phenotypic spectrum of DA for this geographic area, and the role of heredity in the DA genetic determinism in the studied population.


Subject(s)
Anodontia , Algorithms , Anodontia/diagnostic imaging , Anodontia/genetics , Cross-Sectional Studies , Humans , Incisor , Phenotype
6.
Ultramicroscopy ; 170: 86-95, 2016 11.
Article in English | MEDLINE | ID: mdl-27566048

ABSTRACT

This review article discusses the current and future possibilities for the application of in situ transmission electron microscopy to reveal synthesis pathways and functional mechanisms in complex and nanoscale materials. The findings of a group of scientists, representing academia, government labs and private sector entities (predominantly commercial vendors) during a workshop, held at the Center for Nanoscale Science and Technology- National Institute of Science and Technology (CNST-NIST), are discussed. We provide a comprehensive review of the scientific needs and future instrument and technique developments required to meet them.

7.
Microsc Microanal ; 21(6): 1629-1638, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26650072

ABSTRACT

We demonstrate quantitative core-loss electron energy-loss spectroscopy of iron oxide nanoparticles and imaging resolution of Ag nanoparticles in liquid down to 0.24 nm, in both transmission and scanning transmission modes, in a novel, monolithic liquid cell developed for the transmission electron microscope (TEM). At typical SiN membrane thicknesses of 50 nm the liquid-layer thickness has a maximum change of only 30 nm for the entire TEM viewing area of 200×200 µm.

8.
J Am Chem Soc ; 136(15): 5687-96, 2014 Apr 16.
Article in English | MEDLINE | ID: mdl-24654835

ABSTRACT

Metal nanoparticles are commonly supported on metal oxides, but their utility as catalysts is limited by coarsening at high temperatures. Rhodium oxide and rhodium metal nanoparticles on niobate and tantalate supports are anomalously stable. To understand this, the nanoparticle-support interaction was studied by isothermal titration calorimetry (ITC), environmental transmission electron microscopy (ETEM), and synchrotron X-ray absorption and scattering techniques. Nanosheets derived from the layered oxides KCa2Nb3O10, K4Nb6O17, and RbTaO3 were compared as supports to nanosheets of Na-TSM, a synthetic fluoromica (Na0.66Mg2.68(Si3.98Al0.02)O10.02F1.96), and α-Zr(HPO4)2·H2O. High surface area SiO2 and γ-Al2O3 supports were also used for comparison in the ITC experiments. A Born-Haber cycle analysis of ITC data revealed an exothermic interaction between Rh(OH)3 nanoparticles and the layered niobate and tantalate supports, with ΔH values in the range -32 kJ·mol(-1) Rh to -37 kJ·mol(-1) Rh. In contrast, the interaction enthalpy was positive with SiO2 and γ-Al2O3 supports. The strong interfacial bonding in the former case led to "reverse" ripening of micrometer-size Rh(OH)3, which dispersed as 0.5 to 2 nm particles on the niobate and tantalate supports. In contrast, particles grown on Na-TSM and α-Zr(HPO4)2·H2O nanosheets were larger and had a broad size distribution. ETEM, X-ray absorption spectroscopy, and pair distribution function analyses were used to study the growth of supported nanoparticles under oxidizing and reducing conditions, as well as the transformation from Rh(OH)3 to Rh nanoparticles. Interfacial covalent bonding, possibly strengthened by d-electron acid/base interactions, appear to stabilize Rh(OH)3, Rh2O3, and Rh nanoparticles on niobate and tantalate supports.


Subject(s)
Nanoparticles , Niobium/chemistry , Rhodium/chemistry , Tantalum/chemistry , Calorimetry , Microscopy, Electron, Transmission , Oxides/chemistry , Powder Diffraction
9.
Nano Lett ; 12(1): 505-11, 2012 Jan 11.
Article in English | MEDLINE | ID: mdl-22185512

ABSTRACT

Rechargeable, all-solid-state Li ion batteries (LIBs) with high specific capacity and small footprint are highly desirable to power an emerging class of miniature, autonomous microsystems that operate without a hardwire for power or communications. A variety of three-dimensional (3D) LIB architectures that maximize areal energy density has been proposed to address this need. The success of all of these designs depends on an ultrathin, conformal electrolyte layer to electrically isolate the anode and cathode while allowing Li ions to pass through. However, we find that a substantial reduction in the electrolyte thickness, into the nanometer regime, can lead to rapid self-discharge of the battery even when the electrolyte layer is conformal and pinhole free. We demonstrate this by fabricating individual, solid-state nanowire core-multishell LIBs (NWLIBs) and cycling these inside a transmission electron microscope. For nanobatteries with the thinnest electrolyte, ≈110 nm, we observe rapid self-discharge, along with void formation at the electrode/electrolyte interface, indicating electrical and chemical breakdown. With electrolyte thickness increased to 180 nm, the self-discharge rate is reduced substantially, and the NWLIBs maintain a potential above 2 V for over 2 h. Analysis of the nanobatteries' electrical characteristics reveals space-charge limited electronic conduction, which effectively shorts the anode and cathode electrodes directly through the electrolyte. Our study illustrates that, at these nanoscale dimensions, the increased electric field can lead to large electronic current in the electrolyte, effectively shorting the battery. The scaling of this phenomenon provides useful guidelines for the future design of 3D LIBs.


Subject(s)
Electric Power Supplies , Electrolytes/chemistry , Lithium/chemistry , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanotechnology/instrumentation , Energy Transfer , Equipment Design , Equipment Failure Analysis , Particle Size
10.
Microsc Res Tech ; 72(3): 187-96, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19165741

ABSTRACT

Magnetic nanostructures and thin films display novel magnetization reversal behavior as a function of size and shape, which makes them appropriate for a range of technological applications. The spatial resolution of in situ transmission electron microscopy techniques such as Lorentz TEM (LTEM) and off-axis electron holography are well suited to analysis of the magnetic domain structure and magnetization behavior of these magnetic nanostructures and thin films. In this article the various techniques that are applicable are described, including the qualitative LTEM imaging modes and the differential phase contrast technique. In addition, quantitative methods for mapping the magnetic induction via phase reconstruction are discussed. In each case the advantages and limitations are presented. Application of the techniques to various types of magnetic structures is then presented, and the article ends with a short summary and a discussion of future developments in this field.


Subject(s)
Microscopy, Electron, Transmission/methods , Nanostructures/chemistry , Magnetics , Nanostructures/ultrastructure
11.
J Phys Chem B ; 108(20): 6121-3, 2004 May 20.
Article in English | MEDLINE | ID: mdl-18950090

ABSTRACT

Monodispersed FePt nanoparticles are synthesized by reduction of iron(II) acetylacetonate and platinum(II) acetylacetonate with 1,2-hexadecanediol as the reducing reagent in the polyol process. As-prepared FePt nanoparticles are chemically disordered with fcc phase. Transmission electron microscopy (TEM) images show a self-assembled particle array with an average particle size of 3 nm and a standard deviation about 10%. The transformation from chemically disordered fcc to chemically ordered L10 phase is achieved by annealing at 650 degrees C for 30 min in Ar atmosphere where the oxygen level is less than 1 ppm. Magnetic hysteresis measurements show a coercivity of 9.0 kOe at 293K, and 16.7 kOe at 5 K for the annealed FePt nanoparticles.

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