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1.
An Acad Bras Cienc ; 96(1): e20230456, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511745

RESUMO

Vismia japurensis Reichardt is a plant of ecological and chemical importance from which a variety of bioactive substances have been isolated. The current study aimed to establish in vitro cultures of this species as a source of secondary metabolites. Appropriate decontamination treatments and germination tests were performed and, after in vitro culture establishment, the propagated plants were multiplied in a sterile environment to increase the biomass of available experimental material. Seeds showed low contamination and a high germination percentage on Woody Plant Medium (WPM) supplemented with gibberellic acid (both at concentrations of 5 and 10 mg/L). V. japurensis nodal segments rapidly regenerated when first grown in WPM and then transplanted to Murashige and Skoog medium (MS). After 60 days in MS medium, the propagated plants were removed, lyophilized, and extracted with hexane and methanol. The hexane extract was fractionated via open column chromatography, and the substance isolated was purified by high performance liquid chromatography. Structural determination of the isolated substance was carried out using one and two-dimensional nuclear magnetic resonance and mass spectrometry. The isolated substance was identified as 1,8,10-trihydroxy-3,10-dimethyl-9(10H)-anthracenone, which, based on the conducted literature search, is reported for the first time.


Assuntos
Antronas , Hexanos , Plantas , Sementes
2.
J Mech Behav Biomed Mater ; 151: 106353, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38194785

RESUMO

OBJECTIVE: The aim of this study was to evaluate the influence of the thickness of resin-matrix composite blocks manufactured by CAD-CAM on the light transmittance towards different resin-matrix cements or flowable composites. METHODS: Sixty specimens of resin-matrix composite CAD-CAM blocks reinforced with 89 wt% inorganic fillers were cross-sectioned with 2 or 3 mm thicknesses. The specimens were conditioned with adhesive system and divided in groups according to the luting material, namely: two dual-cured resin-matrix cements, two traditional flowable resin-matrix composites, and one thermal-induced flowable resin-matrix composite. Specimens were light-cured at 900 mW/cm2 for 40s. Light transmittance assays were preformed using a spectrophotometer with an integrated monochromator before and after light-curing. Microstructural analysis was performed by optical and scanning electron microscopy (SEM). Nanoindentation tests were performed to evaluate mechanical properties for indirect evaluation of degree of monomers conversion. RESULTS: Optical and SEM images revealed low thickness values for the cementation interfaces for the traditional flowable resin-matrix composite. The cement thickness increased with the size and content of inorganic fillers. The highest light transmittance was recorded for the onlay blocks cemented with the traditional flowable resin-matrix composites while a group cemented with the dual-cured resin-matrix cement revealed the lowest light transmittance. The elastic modulus and hardness increased for specimens with high content of inorganic fillers as well as it increased in function of the light transmittance. CONCLUSIONS: The light transmittance of flowable resin-matrix composites was higher than that for resin-matrix cement after cementation to resin-matrix composites blocks. The type, size, and content of inorganic fillers of the luting material affected the thickness of the cement layer and light transmittance through the materials. CLINICAL RELEVANCE: On chair-side light curing, the transmission of visible light can be interfered by the chemical composition and viscosity of the luting materials. The increase in size and content of inorganic fillers of resin-matrix composites and luting materials can decrease the light transmittance leading to inefficient polymerization.


Assuntos
Resinas Compostas , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Propriedades de Superfície , Cura Luminosa de Adesivos Dentários/métodos , Resinas Compostas/química , Cimentos de Resina/química
3.
Head Face Med ; 19(1): 55, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110992

RESUMO

OBJECTIVE: The main aim of this study was to evaluate the morphological aspects and distribution of granules composed of deproteinized bovine bone mineral (DBBM) and human dentin-derived bone graft (HDBG) into a putty consistency mixture. MATERIALS AND METHODS: DBBM or HDBG were mixed with an alginate-based hydrogel at two different granule/hydrogel ratio (1:1 and 1:3) and divided into four test groups while two control groups were composed of DBBM or HDBG free of hydrogel. Groups of specimens were cross-sectioned for morphological evaluation by scanning electron microscopy (SEM) at backscattered electrons mode. Details on the dimensions and pores' size of DBBM and HDBG were evaluated after mixing different amounts of particles and alginate-based hydrogels. RESULTS: Microscopic analyses revealed a size of DBBM granules ranging from 750 up to 1600 µm while HDBG particles showed particle size ranging from 375 up to 1500 µm. No statistical differences were identified regarding the size of granules (p > 0.5). The mean values of pores' size of DBBM particles were noticed at around 400 µm while HDBG particles revealed micro-scale pores of around 1-3 µm promoted by the dentin tubules (p < 0.05). The lowest distance between particles was at 125 µm for HDBG and 250 µm for DBBM when the particle content was increased. On decreasing the particles' content, the distance between particles was larger for DBBM (~ 1000 µm) and HDBG (~ 1100 µm). In fact, statistically significant differences were found when the content of granules increased (p < 0.05). CONCLUSIONS: The increased content of bioactive ceramic granules in a putty consistency mixture with hydrogel decreased the space among granules that can promote a high ceramic density and stimulate the bone growth over the healing process. Macro-scale pores on bovine bone mineral granules stimulate the formation of blood vessels and cell migration while the micro-scale pores of dentin-derived granules are proper for the adsorption of proteins and growth of osteogenic cells on the bone healing process. CLINICAL SIGNIFICANCE: A high amount of bioactive ceramic granules should be considered when mixing with hydrogels as a putty material since that result in small spaces among granules maintaining the bone volume over the bone healing process. Deproteinized bovine bone mineral granules have macro-scale pores providing an enhanced angiogenesis while dentin-derived granules possess only micro-scale pores for the adsorption of proteins and proliferation of osteogenic cells on the bone healing process. Further studies should evaluate the combination of different bioactive ceramic materials for enhanced bone healing.


Assuntos
Substitutos Ósseos , Transplante Ósseo , Humanos , Animais , Bovinos , Transplante Ósseo/métodos , Minerais , Alginatos , Hidrogéis , Dentina , Regeneração Óssea
4.
Front Cell Infect Microbiol ; 13: 1169552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829607

RESUMO

Introduction: Zoonotic transmission is a challenge for the control and elimination of malaria. It has been recorded in the Atlantic Forest, outside the Amazon which is the endemic region in Brazil. However, only very few studies have assessed the antibody response, especially of IgM antibodies, in Neotropical primates (NP). Therefore, in order to contribute to a better understanding of the immune response in different hosts and facilitate the identification of potential reservoirs, in this study, naturally acquired IgM antibody responses against Plasmodium antigens were evaluated, for the first time, in NP from the Atlantic Forest. Methods: The study was carried out using 154 NP samples from three different areas of the Atlantic Forest. IgM antibodies against peptides of the circumsporozoite protein (CSP) from different Plasmodium species and different erythrocytic stage antigens were detected by ELISA. Results: Fifty-nine percent of NP had IgM antibodies against at least one CSP peptide and 87% against at least one Plasmodium vivax erythrocytic stage antigen. Levels of antibodies against PvAMA-1 were the highest compared to the other antigens. All families of NP showed IgM antibodies against CSP peptides, and, most strikingly, against erythrocytic stage antigens. Generalized linear models demonstrated that IgM positivity against PvCSP and PvAMA-1 was associated with PCR-detectable blood-stage malaria infection and the host being free-living. Interestingly, animals with IgM against both PvCSP and PvAMA-1 were 4.7 times more likely to be PCR positive than animals that did not have IgM for these two antigens simultaneously. Discussion: IgM antibodies against different Plasmodium spp. antigens are present in NP from the Atlantic Forest. High seroprevalence and antibody levels against blood-stage antigens were observed, which had a significant association with molecular evidence of infection. IgM antibodies against CSP and AMA-1 may be used as a potential marker for the identification of NP infected with Plasmodium, which are reservoirs of malaria in the Brazilian Atlantic Forest.


Assuntos
Malária , Plasmodium , Animais , Brasil/epidemiologia , Formação de Anticorpos , Proteínas de Protozoários , Imunoglobulina M , Estudos Soroepidemiológicos , Antígenos de Protozoários , Malária/veterinária , Primatas , Florestas , Anticorpos Antiprotozoários , Peptídeos , Plasmodium vivax
5.
Clin Oral Investig ; 27(9): 5679-5693, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37592003

RESUMO

OBJECTIVES: The aim of this in vitro study was to evaluate the light transmission through five different resin-matrix composites regarding the inorganic filler content. METHODS: Resin-matrix composite disc-shaped specimens were prepared on glass molds. Three traditional resin-matrix composites contained inorganic fillers at 74, 80, and 89 wt. % while two flowable composites revealed 60 and 62.5 wt. % inorganic fillers. Light transmission through the resin-matrix composites was assessed using a spectrophotometer with an integrated monochromator before and after light curing for 10, 20, or 40s. Elastic modulus and nanohardness were evaluated through nanoindentation's tests, while Vicker's hardness was measured by micro-hardness assessment. Chemical analyses were performed by FTIR and EDS, while microstructural analysis was conducted by optical microscopy and scanning electron microscopy. Data were evaluated using two-way ANOVA and Tukey's test (p < 0.05). RESULTS: After polymerization, optical transmittance increased for all specimens above 650-nm wavelength irradiation since higher light exposure time leads to increased light transmittance. At 20- or 40-s irradiation, similar light transmittance was recorded for resin composites with 60, 62, 74, or 78-80 wt. % inorganic fillers. The lowest light transmittance was recorded for a resin-matrix composite reinforced with 89 wt. % inorganic fillers. Thus, the size of inorganic fillers ranged from nano- up to micro-scale dimensions and the high content of micro-scale inorganic particles can change the light pathway and decrease the light transmittance through the materials. At 850-nm wavelength, the average ratio between polymerized and non-polymerized specimens increased by 1.6 times for the resin composite with 89 wt. % fillers, while the composites with 60 wt. % fillers revealed an increased ratio by 3.5 times higher than that recorded at 600-nm wavelength. High mean values of elastic modulus, nano-hardness, and micro-hardness were recorded for the resin-matrix composites with the highest inorganic content. CONCLUSIONS: A high content of inorganic fillers at 89 wt.% decreased the light transmission through resin-matrix composites. However, certain types of fillers do not interfere on the light transmission, maintaining an optimal polymerization and the physical properties of the resin-matrix composites. CLINICAL SIGNIFICANCE: The type and content of inorganic fillers in the chemical composition of resin-matrix composites do affect their polymerization mode. As a consequence, the clinical performance of resin-matrix composites can be compromised, leading to variable physical properties and degradation.


Assuntos
Odontologia , Vidro , Cromatografia Gasosa , Módulo de Elasticidade , Dureza
6.
Clin Oral Implants Res ; 34(11): 1198-1216, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37577958

RESUMO

AIM: This bibliometric study analyzed the characteristics of the 100 most cited articles on bone grafts in dentistry. MATERIALS AND METHODS: A database search was performed on the Web of Science Core Collection using a specific search strategy. Scopus and Google Scholar were also consulted for citation comparisons. Data extracted included: title, citation metrics, publication year, journal, study design, graft material, surgical technique, authors, institution, and country. Bibliometric networks were generated using VOSviewer. RESULTS: The identified articles were published between 1991 and 2019. Citation counts ranged from 120 to 1161 (mean: 240, 30). Clinical Oral Implants Research was the most cited journal (5175 citations; 25/100). Xenogeneic bone graft material was the most frequently used (5130 citations; 22/100). Europe had 62 articles (14,604 citations), and the United States was the most prominent country (5209 citations; 22/100). The University of Bern had the highest number of citations (2565 citations; 13/100), with Buser D as the author with the largest number of articles (2648 citations; 12/100). CONCLUSION: This study shows the scientific progress on bone grafts in dentistry. The use of xenogeneic grafts for horizontal and/or vertical ridge augmentation was the most prominent trend.


Assuntos
Bibliometria , Transplante Ósseo , Estados Unidos , Odontologia
7.
Health Inf Manag ; : 18333583231180294, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37462322

RESUMO

BACKGROUND: In Portugal, trained physicians undertake the clinical coding process, which serves as the basis for hospital reimbursement systems. In 2017, the classification version used for coding of diagnoses and procedures for hospital morbidity changed from the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) to the International Classification of Diseases, Tenth Revision, Clinical Modification/Procedure Coding System (ICD-10-CM/PCS). OBJECTIVE: To assess the perceptions of medical coders on the transition of the clinical coding process from ICD-9-CM to ICD-10-CM/PCS in terms of its impact on data quality, as well as the major differences, advantages, and problems they faced. METHOD: We conducted an observational study using a web-based survey submitted to medical coders in Portugal. Survey questions were based on a literature review and from previous focus group studies. RESULTS: A total of 103 responses were obtained from medical coders with experience in the two versions of the classification system (i.e. ICD-9-CM and ICD-10-CM/PCS). Of these, 82 (79.6%) medical coders preferred the latest version and 76 (73.8%) considered that ICD-10-CM/PCS guaranteed higher quality of the coded data. However, more than half of the respondents (N = 61; 59.2%) believed that more time for the coding process for each episode was needed. CONCLUSION: Quality of clinical coded data is one of the major priorities that must be ensured. According to the medical coders, the use of ICD-10-CM/PCS appeared to achieve higher quality coded data, but also increased the effort. IMPLICATIONS: According to medical coders, the change off classification systems should improve the quality of coded data. Nevertheless, the extra time invested in this process might also pose a problem in the future.

8.
Vet Parasitol Reg Stud Reports ; 43: 100903, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37451759

RESUMO

Spotted fever caused by the bacterium Rickettsia parkeri, and canine rangeliosis caused by the protozoan Rangelia vitalii, are emerging or re-emerging tick-borne diseases in Brazil, where the main tick vectors are Amblyomma ovale and Amblyomma aureolatum, respectively. In the present study, we evaluated exposure to R. parkeri and R. vitalii infection among domestic (Canis lupus familiaris) and wild (Cerdocyon thous) canids sharing living areas within an Atlantic Forest area of southern Brazil. Four different domestic dogs and three different wild canids were captured. Most of the ticks collected from either domestic or wild canids were identified as A. ovale and A. aureolatum. DNA of R. parkeri was amplified from 14% of the A. ovale specimens. Two domestic dogs and two wild canids were seroreactive to R. parkeri antigens with high endpoint titers (>1024). Rangelia vitalii DNA was detected in two wild canids; one of them was resampled 93 days later, again infected by R. vitalii. We report exposure/infection of domestic dogs and wild canids to R. vitalii and/or R. parkeri-infected ticks in an Atlantic Forest area shared by both canid species, indicating that they also shared the same populations of the tick vectors, A. aureolatum and A. ovale. While A. ovale, A. aureolatum, R. parkeri, R. vitalii and C. thous, are all native to the Atlantic Forest, further studies are needed to evaluate the impact of an exotic canine species - C. lupus familiaris - on the enzootic cycles of R. vitalii and R. parkeri, as well as the possible role of domestic dogs in emergence and re-emergence of R. parkeri-spotted fever in humans and canine rangeliosis, respectively.


Assuntos
Canidae , Piroplasmida , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Humanos , Animais , Cães , Brasil/epidemiologia , Piroplasmida/genética , Florestas , Rickettsiose do Grupo da Febre Maculosa/veterinária , Amblyomma
9.
JMIR Res Protoc ; 12: e45823, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37335606

RESUMO

BACKGROUND: Considering the soaring health-related costs directed toward a growing, aging, and comorbid population, the health sector needs effective data-driven interventions while managing rising care costs. While health interventions using data mining have become more robust and adopted, they often demand high-quality big data. However, growing privacy concerns have hindered large-scale data sharing. In parallel, recently introduced legal instruments require complex implementations, especially when it comes to biomedical data. New privacy-preserving technologies, such as decentralized learning, make it possible to create health models without mobilizing data sets by using distributed computation principles. Several multinational partnerships, including a recent agreement between the United States and the European Union, are adopting these techniques for next-generation data science. While these approaches are promising, there is no clear and robust evidence synthesis of health care applications. OBJECTIVE: The main aim is to compare the performance among health data models (eg, automated diagnosis and mortality prediction) developed using decentralized learning approaches (eg, federated and blockchain) to those using centralized or local methods. Secondary aims are comparing the privacy compromise and resource use among model architectures. METHODS: We will conduct a systematic review using the first-ever registered research protocol for this topic following a robust search methodology, including several biomedical and computational databases. This work will compare health data models differing in development architecture, grouping them according to their clinical applications. For reporting purposes, a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 flow diagram will be presented. CHARMS (Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies)-based forms will be used for data extraction and to assess the risk of bias, alongside PROBAST (Prediction Model Risk of Bias Assessment Tool). All effect measures in the original studies will be reported. RESULTS: The queries and data extractions are expected to start on February 28, 2023, and end by July 31, 2023. The research protocol was registered with PROSPERO, under the number 393126, on February 3, 2023. With this protocol, we detail how we will conduct the systematic review. With that study, we aim to summarize the progress and findings from state-of-the-art decentralized learning models in health care in comparison to their local and centralized counterparts. Results are expected to clarify the consensuses and heterogeneities reported and help guide the research and development of new robust and sustainable applications to address the health data privacy problem, with applicability in real-world settings. CONCLUSIONS: We expect to clearly present the status quo of these privacy-preserving technologies in health care. With this robust synthesis of the currently available scientific evidence, the review will inform health technology assessment and evidence-based decisions, from health professionals, data scientists, and policy makers alike. Importantly, it should also guide the development and application of new tools in service of patients' privacy and future research. TRIAL REGISTRATION: PROSPERO 393126; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=393126. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/45823.

10.
J Mech Behav Biomed Mater ; 143: 105943, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37276650

RESUMO

Surface modification of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) using lasers for adhesion enhancement with resin-matrix cement has been increasingly explored. However, Y-TZP is chemically inert and non-reactive, demanding surface modification using alternative approaches to enhance its bond strength to resin-matrix cements. The main aim of this study was to conduct an integrative review on the influence of ultrashort pulse laser patterning of zirconia (3Y-TZP) for enhanced bonding to resin-matrix cements. An electronic search was performed on web of science, SCOPUS, Pubmed/Medline, Google Scholar and EMBASE using a combination of the following search items: zirconia, 3Y-TZP, surface modification, laser surface treatment, AND laser, ultrashortpulse laser, bonding, adhesion, and resin cement. Articles published in the English language, up to January 2022, were included regarding the influence of surface patterning on bond strength of Y-TZP to resin-matrix cements. Out of the 12 studies selected for the present review 10 studies assessed femtosecond lasers while 2 studies assessed picosecond lasers. Ultrashort pulsed laser surface patterning successfully produced different surface morphological aspects without damaging the bulk properties of zirconia. Contrarily, defects such as micro-cracks occurs after surface modification using traditional methods such as grit-blasting or long-pulsed laser patterning. Ultrashort pulsed laser surface patterning increase bond strength of zirconia to resin-matrix cements and therefore such alternative physical method should be considered in dentistry. Also, surface defects were avoided using ultrashort pulsed laser surface patterning, which become the major advantage when compared with traditional physical methods or long pulse laser patterning.


Assuntos
Colagem Dentária , Cimentos de Resina , Propriedades de Superfície , Cimentos de Resina/química , Teste de Materiais , Lasers , Zircônio/química , Ítrio/química , Resistência ao Cisalhamento , Odontologia
11.
Stud Health Technol Inform ; 302: 1013-1014, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37203557

RESUMO

This short paper describes a remote monitoring platform proposed in the Inno4health project. The platform aims to guide patients and clinicians during the treatment of lower limb vascular disorders, namely, to correct abnormal foot pressure and temperature to prevent diabetic foot ulcers and to monitor interface pressure, leg position and elevation for venous ulcers patients.


Assuntos
Pé Diabético , Extremidade Inferior , Humanos , Pé Diabético/terapia ,
12.
Stud Health Technol Inform ; 302: 516-520, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37203739

RESUMO

The application of machine learning (ML) algorithms to electronic health records (EHR) data allows the achievement of data-driven insights on various clinical problems and the development of clinical decision support (CDS) systems to improve patient care. However, data governance and privacy barriers hinder the use of data from multiple sources, especially in the medical field due to the sensitivity of data. Federated learning (FL) is an attractive data privacy-preserving solution in this context by enabling the training of ML models with data from multiple sources without any data sharing, using distributed remotely hosted datasets. The Secur-e-Health project aims at developing a solution in terms of CDS tools encompassing FL predictive models and recommendation systems. This tool may be especially useful in Pediatrics due to the increasing demands on Pediatric services, and the current scarcity of ML applications in this field compared to adult care. Herein we provide a description of the technical solution proposed in this project for three specific pediatric clinical problems: childhood obesity management, pilonidal cyst post-surgical care and retinography imaging analysis.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Obesidade Infantil , Telemedicina , Adulto , Humanos , Criança , Algoritmos , Sistemas Inteligentes , Privacidade
13.
Clin Oral Investig ; 27(7): 3331-3345, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37069409

RESUMO

OBJECTIVE: The purpose of this study was to perform an integrative review on laser texturing the inner surface of lithium disilicate-reinforced glass ceramic or zirconia to increase their bond strength to resin-matrix cements. MATERIALS AND METHOD: A bibliographic review was performed on PubMed using the following search terms: "zirconia" OR "lithium disilicate" AND "laser" AND "surface" OR "roughness" AND "bond strength" AND "luting agent" OR "resin cement." Studies published in English language until March 15, 2023, were selected regarding the purpose of this study. RESULTS: A total of fifty-six studies were identified althoug thirteen studies were selected. The findings revealed that zirconia surfaces were significantly modified after laser irradiation resulting in macro-scale aligned retentive regions with depth values ranging from 50 to 120 µm. Average roughness values of laser-textured zirconia by Er,Cr:YSGG laser (~ 0.83 µm) were quite similar when compared to grit-blasted zirconia surfaces (~ 0.9 µm) although roughness increased up to 2.4 µm depending on the laser type and parameters. Lithium disilicate-reinforced glass ceramics textured with Er:YAG revealed an average roughness of around 3.5 µm while surfaces textured using Nd:YAG laser revealed an average roughness of 2.69 µm; that was quite similar to the roughness values recorded for etched surfaces (2.64 µm). The shear bond strength (SBS) values of zirconia surfaces textured on Nd:YVO4 laser irradiation were slightly higher (~ 33.5 MPa) than those recorded for grit-blasted zirconia surfaces (28 MPa). Laser-textured zirconia surfaces on CO2 laser revealed higher SBS values (18.1 ±0.8 MPa) than those (9.1 ± 0.56 MPa) recorded for untreated zirconia surfaces. On lithium disilicate-reinforced glass ceramics, higher SBS values to resin-matrix cements were recorded for specimens textured with a combination of fractional CO2 laser irradiation and HF acid etching (~ 22-24 MPa) when compared with grit-blasted specimens (12.2 MPa). Another study revealed SBS values at around 27.5 MPa for Er:YAG-textured lithium disilicate-reinforced glass ceramics to resin-matrix cements. CONCLUSIONS: The laser irradiation at high power increases the roughness of the inner surface of lithium disilicate-reinforced glass ceramic or zirconia leading to an enhanced bond strength to resin-matrix cements. Thus, the laser type and irradiation parameters can be adjusted to enhance the macro- and micro-scale retention of zirconia and glass ceramic surfaces to resin-matrix cements. CLINICAL RELEVANCE: Alternative methods for surface modification of lithium disilicate-reinforced glass ceramic and zirconia surfaces have been assessed to provide proper morphological aspects for enhanced adhesion to resin-matrix cements. An increase in the bond strength of glass ceramics or zirconia to resin-matrix cements can improve the long-term performance of cemented prosthetic structures in the oral cavity.


Assuntos
Colagem Dentária , Lasers de Estado Sólido , Cimentos de Resina/química , Lítio , Dióxido de Carbono , Propriedades de Superfície , Cerâmica/química , Porcelana Dentária/química , Resistência ao Cisalhamento , Teste de Materiais , Zircônio/química
14.
J Funct Biomater ; 14(3)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36976072

RESUMO

PURPOSE: This study aimed to assess the layer thickness and microstructure of traditional resin-matrix cements and flowable resin-matrix composites at dentin and enamel to composite onlay interfaces after cementation on low loading magnitude. MATERIALS AND METHODS: Twenty teeth were prepared and conditioned with an adhesive system for restoration with resin-matrix composite onlays manufactured by CAD-CAM. On cementation, tooth-to-onlay assemblies were distributed into four groups, including two traditional resin-matrix cements (groups M and B), one flowable resin-matrix composite (group G), and one thermally induced flowable composite (group V). After the cementation procedure, assemblies were cross-sectioned for inspection by optical microscopy at different magnification up to ×1000. RESULTS: The layer thickness of resin-matrix cementation showed the highest mean values at around 405 µm for a traditional resin-matrix cement (group B). The thermally induced flowable resin-matrix composites showed the lowest layer thickness values. The resin-matrix layer thickness revealed statistical differences between traditional resin cement (groups M and B) and flowable resin-matrix composites (groups V and G) (p < 0.05). However, the groups of flowable resin-matrix composites did not reveal statistical differences (p < 0.05). The thickness of the adhesive system layer at around 7 µm and 12 µm was lower at the interfaces with flowable resin-matrix composites when compared to the adhesive layer at resin-matrix cements, which ranged from 12 µm up to 40 µm. CONCLUSIONS: The flowable resin-matrix composites showed adequate flowing even though the loading on cementation was performed at low magnitude. Nevertheless, significant variation in thickness of the cementation layer was noticed for flowable resin-matrix composites and traditional resin-matrix cements that can occur in chair-side procedures due to the clinical sensitivity and differences in rheological properties of the materials.

15.
Materials (Basel) ; 16(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36837188

RESUMO

In dentistry, clinicians mainly use dual-cured or light-cured resin-matrix cements to achieve a proper polymerization of the organic matrix leading to enhanced physical properties of the cement. However, several parameters can affect the polymerization of resin-matrix cements. The main aim of the present study was to perform a scoping review on the degree of conversion (DC) of the organic matrix, the polymerization, and the light transmittance of different resin-matrix cements used in dentistry. A search was performed on PubMed using a combination of the following key terms: degree of conversion, resin cements, light transmittance, polymerization, light curing, and thickness. Articles in the English language published up to November 2022 were selected. The selected studies' results demonstrated that restorative structures with a thickness higher than 1.5 mm decrease the light irradiance towards the resin-matrix cement. A decrease in light transmission provides a low energy absorption through the resin cement leading to a low DC percentage. On the other hand, the highest DC percentages, ranging between 55 and 75%, have been reported for dual-cured resin-matrix cements, although the polymerization mode and exposure time also influence the DC of monomers. Thus, the polymerization of resin-matrix cements can be optimized taking into account different parameters of light-curing, such as adequate light distance, irradiance, exposure time, equipment, and wavelength. Then, optimum physical properties are achieved that provide a long-term clinical performance of the cemented restorative materials.

16.
Health Econ Rev ; 13(1): 11, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781709

RESUMO

INTRODUCTION: Healthcare expenditure, a common input used in health systems efficiency analyses is affected by population age structure. However, while age structure is usually considered to adjust health system outputs, health expenditure and other inputs are seldom adjusted. We propose methods for adjusting Health Expenditure per Capita (HEpC) for population age structure on health system efficiency analyses and assess the goodness-of-fit, correlation, reliability and disagreement of different approaches. METHODS: We performed a worldwide (188 countries) cross-sectional study of efficiency in 2015, using a stochastic frontier analysis. As single outputs, healthy life expectancy (HALE) at birth and at 65 years-old were considered in different models. We developed five models using as inputs: (1) HEpC (unadjusted); (2) age-adjusted HEpC; (3) HEpC and the proportion of 0-14, 15-64 and 65 + years-old; (4) HEpC and 5-year age-groups; and (5) HEpC ageing index. Akaike and Bayesian information criteria, Spearman's rank correlation, intraclass correlation coefficient and information-based measure of disagreement were computed. RESULTS: Models 1 and 2 showed the highest correlation (0.981 and 0.986 for HALE at birth and HALE at 65 years-old, respectively) and reliability (0.986 and 0.988) and the lowest disagreement (0.011 and 0.014). Model 2, with age-adjusted HEpC, presented the lowest information criteria values. CONCLUSIONS: Despite different models showing good correlation and reliability and low disagreement, there was important variability when age structure is considered that cannot be disregarded. The age-adjusted HE model provided the best goodness-of-fit and was the closest option to the current standard.

18.
Odontology ; 111(3): 541-553, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36495398

RESUMO

The purpose of this study was to perform an integrative review on the effects of cranberry and grape seed extracts concerning the disinfection of root canals maintaining the strength of the remnant tooth tissues' structure. A bibliographical search was carried out on the PubMed electronic platform using the following key terms: cranberry, grape seed, vaccinium macrocarpon, proanthocyanidin, antibacterial, antimicrobial, decontamination, disinfection, bacteria removal, bacteria eradication, bacteria elimination, endodontic, root canal, faecalis, and strength. The inclusion criteria involved articles published in the English language, until March, 2022, reporting the antibacterial effect of grape seed and cranberry extracts. Of 185 studies identified, 13 studies were selected for the present review. The grape seed extract (GSE), composed of proanthocyanidins, showed an antioxidant activity against the main bacteria found in endodontic secondary infection. The percentage of bacteria removal was recorded at around 96.97% by using GSE. Studies on cranberry extracts, which are composed of proanthocyanidins, revealed antimicrobial effects against bacteria related to periodontitis and dental caries. Additionally, GSE or cranberry allowed the dentin collagen cross-linking that preserved the 3D collagen network leading to the maintenance of the strength of the remnant tooth structure. However, the contaminated smear layer could not be removed by using only GSE or cranberry. Cranberry extracts and GSE revealed a significant antimicrobial activity in endodontic disinfection without changing the mechanical properties of the remnant dentin tissues. Furthermore, those components can be associated with traditional compounds to enhance their antimicrobial effects and eliminate the smear layer.


Assuntos
Anti-Infecciosos , Cárie Dentária , Extrato de Sementes de Uva , Proantocianidinas , Vaccinium macrocarpon , Vitis , Proantocianidinas/farmacologia , Proantocianidinas/química , Vaccinium macrocarpon/química , Cavidade Pulpar , Desinfecção , Extrato de Sementes de Uva/farmacologia , Extrato de Sementes de Uva/química , Anti-Infecciosos/farmacologia , Colágeno , Antibacterianos/farmacologia , Sementes
19.
Odontology ; 111(2): 310-327, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36370322

RESUMO

The main aim of this study was to perform an integrative review on the toxic effects of resin-matrix cements and their products in contact with fibroblasts or mesenchymal cells. A bibliographic search was performed on PubMed using the following search terms: "cytotoxicity" AND "fibroblast" OR "epithelial" OR "mesenchymal" AND "polymerization" OR "degree of conversion" OR "methacrylate" OR "monomer" AND "resin cement" OR "resin-based cement". The initial search in the available database yielded a total of 277 articles of which 21 articles were included in this review. A decrease in the viability of mouse fibroblasts ranged between 13 and 15% that was recorded for different resin-matrix cements after light curing exposure for 20 s. The viability of human fibroblasts was recorded at 83.11% after light curing for 20 s that increased up to 90.9% after light curing exposure for 40 s. Most of the studies linked the highest toxicity levels when the cells were in contact with Bis-GMA followed by UDMA, TEGDMA and HEMA. Resin-matrix cements cause a cytotoxic reaction when in contact with fibroblasts or mesenchymal cells due to the release of monomers from the polymeric matrix. The amount of monomers released from the resin matrix and their cytotoxicity depends on the polymerization parameters.


Assuntos
Ácidos Polimetacrílicos , Cimentos de Resina , Camundongos , Animais , Humanos , Cimentos de Resina/toxicidade , Ácidos Polimetacrílicos/toxicidade , Metacrilatos/toxicidade , Bis-Fenol A-Glicidil Metacrilato/farmacologia , Fibroblastos , Polimerização , Teste de Materiais
20.
Artigo em Inglês | MEDLINE | ID: mdl-36429951

RESUMO

This systematic review aims at providing an overview of the state of the art regarding smart wearable systems (SWS) applications to monitor the status of patients suffering from vascular disorders of the lower extremity. Peer-reviewed literature has been analyzed to identify employed data collection methods, system characteristics, and functionalities, and research challenges and limitations to be addressed. The Medline (PubMed) and SCOPUS databases were considered to search for publications describing SWS for remote or continuous monitoring of patients suffering from intermittent claudication, venous ulcers, and diabetic foot ulcers. Publications were first screened based on whether they describe an SWS applicable to the three selected vascular disorders of the lower extremity, including data processing and output to users. Information extracted from publications included targeted disease, clinical parameters to be measured and wearable devices used; system outputs to the user; system characteristics, including capabilities of remote or continuous monitoring or functionalities resulting from advanced data analyses, such as coaching, recommendations, or alerts; challenges and limitations reported; and research outputs. A total of 128 publications were considered in the full-text analysis, and 54 were finally included after eligibility criteria assessment by four independent reviewers. Our results were structured and discussed according to three main topics consisting of data collection, system functionalities, and limitations and challenges.


Assuntos
Pé Diabético , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica , Atenção à Saúde , Extremidade Inferior
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