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AIM: To present a scientometric analysis of the entire body of scientific publications in the field of vital pulp therapy (VPT) and analyse the research trends and popular topics. METHODOLOGY: A comprehensive literature search was conducted in the Web of Science and Scopus databases on 21 August 2020 to identify all articles related to VPT. The publications were reviewed and basic research parameters were collected, including publication year, patterns of authorship, geographical distribution of scientific productions, journals, h-index, study design and keyword analysis. Web of Science, Scopus and Google Scholar databases were used for the citation analysis of the ten top cited articles. The data were analysed using VOSviewer and visualized by tables and diagrams. RESULTS: In total, 1197 VPT-associated items were identified from 64 countries in 176 journals. The majority of papers were published in the Journal of Endodontics. The United States of America was the leading country for number of publications, citations, h-index and collaborations. The distribution of articles based on study design was as follows: basic science (35%), clinical (27%), observational studies (26%) and review publications (12%). The most frequently occurring keywords were pulpotomy, mineral trioxide aggregate, calcium hydroxide and direct pulp capping. CONCLUSIONS: This scientometric analysis outlines the evolutionary trends and the productivity of researchers and countries in the field of vital pulp therapy. Research output is dominated by basic science articles involving innovative materials published in high impact factor dental journals.
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Bibliometria , Endodontia , Bases de Dados Factuais , Pulpotomia , Projetos de Pesquisa , Estados UnidosRESUMO
AIM: To investigate pulp responses after pulpotomy and EDTA conditioning of pulp chamber dentinal walls with or without the placement of a collagenous scaffold in the experimental model of miniature swine teeth. METHODOLOGY: Forty-two fully developed permanent premolars and molars of healthy miniature swines were used. After preparation of pulp exposures through Class I cavities, the tissue of the pulp chamber was completely removed. The haemorrhage was controlled, and the root pulp was protected using a polyurethane film. The circumpulpal pulp chamber dentine was treated for 3 min with normal saline (group 1), or 17% EDTA solution (groups 2 and 3). The film was removed, and the pulp chamber cavities were left empty (groups 1 and 2), or filled with swine collagenous sponge (group 3). The access cavities were restored with a Teflon disc and glass ionomer. Teeth were evaluated histo-morphologically after 10 weeks. Data were compared using the nonparametric Fisher's exact test. RESULTS: Teeth after treatment of dentine with saline (group 1) were associated with no or only traces of hard tissue formation along the root canal walls. Atubular tertiary dentine deposition in the form of matrix deposition along root canal walls, or dentine bridge formation at the orifice of root canals or complete pulp canal obliteration, was found after treatment of dentine with EDTA in both experiments (groups 2 and 3). Significantly different types of mineralization in the root canals of groups 2 and 3 were seen (P = 0.001). Tissue changes in the pulp cavity, characterized by soft tissue growth and osteodentine or atubular tertiary dentine formation, were only seen after EDTA conditioning of dentine, in 6.2% of the teeth without scaffold and 64.7% of the teeth with scaffold application. Newly deposited mineralized matrix in the pulp chamber was always in continuation with hard tissue deposited in the root canals. CONCLUSIONS: The EDTA conditioning of pulp cavity dentinal walls after pulpotomy induced dentinogenic events in the root pulp. Application of collagenous scaffold in the pulp chamber enhanced soft tissue growth and mineralized tissue formation along the treated circumpulpal dentine.
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Dentina Secundária , Dentinogênese , Animais , Dentina , Ácido Edético , Suínos , Porco MiniaturaRESUMO
The aim of the study was to evaluate the elution of Triethylene glycol dimethacrylate (TEGDMA), Urethane dimethacrylate (UDMA), Bisphenol A glycerolate dimethacrylate (BisGMA), and Bisphenol A (BPA), from a dual-cured resin cement through human dentin, under constant positive pulpal pressure. Ten human dentin disks were adjusted into a custom made testing device and transparent glass slabs were luted with Variolink II cement, under a steady pressure. The device was filled with Ringer's solution and a pressure of 14.1 cm H2O was applied. Eluates were retrieved from each one of the ten specimens at 9 time interval. All the samples were analyzed by High Performance Liquid Chromatography (HPLC). TEGDMA was detected from the second and UDMA was detected from the fourth time interval and then. The highest average concentration of TEGDMA and UDMA was detected in the 3 day time interval. Time had a significant effect on their elution. BPA and BisGMA were not detected in any sample of any time interval. The clinical relevance of the present study is that the concentration of the eluted monomers, under the conditions that were chosen, did not reach toxic levels for the pulp.
Assuntos
Dentina , Cimentos de Resina , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Cimentos de Ionômeros de Vidro , Humanos , Metacrilatos , Polietilenoglicóis , Ácidos PolimetacrílicosRESUMO
AIM: To evaluate setting time, pH, solubility and surface roughness of MTA+ and ProRoot MTA and characterize their hydration under several curing conditions. METHODOLOGY: Specimens were prepared to evaluate setting time (n = 6 for each group, specimen dimensions 10 × 8 × 5 mm), solubility (n = 6 for each group, specimen dimension 20 mm in diameter and 1.5 mm thick) after 1 and 28 days, pH (n = 10 for each group, specimen dimensions 10 mm in diameter and 1 mm thick) after 1, 7, 14, 21 and 28 days and surface roughness (n = 10 for each group, specimen dimensions 4 mm in diameter and 3 mm high) after 28 days when cements were cured at 95% humidity or immersed in saline or HBSS at 37 °C. The powder and liquid were mechanically mixed by an amalgamator. The set materials were characterized using X-ray diffraction analysis, scanning electron microscopy and X-ray energy-dispersive analysis. Statistical comparisons were employed using one-way anova. The level of significance was set at P = 0.05. RESULTS: Setting time was significantly shorter when cements were cured at 95% humidity compared to those in saline (P < 0.001) and HBSS (P < 0.001). Setting time of MTA+ was significantly shorter than that of ProRoot MTA (P < 0.001), which had a significantly higher pH than MTA+ (P < 0.05) for all periods and immersion liquids. After immersion in saline, MTA+ was significantly less soluble than ProRoot MTA (P < 0.001); when immersed in HBSS, no significant difference was found (P = 1.00). The surface roughness of both cements was affected when exposed to HBSS (P < 0.001 for both cements) and saline (P < 0.001 for both cements). Storage in HBSS created a homogenous surface; incubation in saline or humidity created a biphasic surface. The main crystalline phases in both cements were tricalcium silicate, bismuth oxide and calcium hydroxide. CONCLUSIONS: MTA+ had a shorter setting time than ProRoot MTA, promoted lower pH and had lower solubility in saline. Curing conditions affected the surface roughness and microstructure of the cements.
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Compostos de Alumínio/química , Compostos de Cálcio/química , Teste de Materiais , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Silicatos/química , Bismuto/química , Hidróxido de Cálcio/química , Combinação de Medicamentos , Umidade , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Solubilidade , Propriedades de Superfície , Temperatura , Fatores de Tempo , Difração de Raios XRESUMO
How circulating inflammatory mediators change upon sepsis progression has not been studied. We studied the follow-up changes of circulating vasoactive peptides and cytokines until the improvement or the worsening of a patient and progression into specific organ dysfunctions. In a prospective study, concentrations of tumor necrosis factor-alpha (TNFα), interleukin (IL)-6, IL-8, IL-10, interferon-gamma (IFNγ), endocan and angiopoietin-2 (Ang-2) were measured in serum by an enzyme immunoassay in 175 patients at baseline; this was repeated within 24 h upon progression into new organ dysfunction (n = 141) or improvement (n = 34). Endocan and Ang-2 were the only parameters that were significantly increased among patients who worsened. Any increase of endocan was associated with worsening with odds ratio 16.65 (p < 0.0001). This increase was independently associated with progression into acute respiratory distress syndrome (ARDS) as shown after logistic regression analysis (odds ratio 2.91, p: 0.002). Changes of circulating cytokines do not mediate worsening of the critically ill patients. Instead endocan and Ang2 are increased and this may be interpreted as a key-playing role in the pathogenesis of ARDS and septic shock. Any increase of endocan is a surrogate of worsening of the clinical course.
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Proteínas de Neoplasias/sangue , Proteoglicanas/sangue , Sepse/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocinas/sangue , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Estudos Prospectivos , Síndrome do Desconforto Respiratório/patologia , Soro/química , Proteínas de Transporte Vesicular/sangueRESUMO
Hepatocellular carcinoma (HCC) may still develop in chronic hepatitis B (CHB) patients treated with lamivudine. Whether HCC rates are comparable in patients treated with the current first-line antivirals remains uncertain. We estimated the incidence and evaluated predictors of HCC in a large nationwide prospective cohort (HepNet.Greece) of HBeAg-negative CHB patients treated with entecavir. HBeAg-negative CHB patients from the same cohort who were initially treated with lamivudine were used as controls. We included 321 patients treated with entecavir for a median of 40 months and 818 patients treated initially with lamivudine for a median of 60 months. In the entecavir group, HCC developed in 4 of 321 (1.2%) patients at a median of 1.5 (range: 1.0-4.5) years, while the cumulative HCC incidence was significantly higher in cirrhotics than noncirrhotics (1, 3, 5 years: 0%, 3%, 9% vs 1%, 1%, 1%; P = 0.024) and in older patients (P = 0.026). Entecavir compared with lamivudine group patients had lower HCC incidence (1, 3, 5 years: 0.3%, 1.2%, 2.8% vs 0.7%, 3.8%, 5.6%; P = 0.024). However, in multivariable Cox regression analysis, the HCC risk was independently associated with older age (P < 0.001), male gender (P = 0.011) and cirrhosis (P = 0.025), but not with the initial agent. In conclusion, our large nationwide study indicates that the HCC risk remains increased in entecavir-treated HBeAg-negative CHB patients with cirrhosis, particularly of older age, at least for the first 5 years. The HCC risk does not seem to be significantly reduced with entecavir compared with antiviral therapy starting with lamivudine.
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Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Guanina/análogos & derivados , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Adulto , Estudos de Coortes , Feminino , Grécia/epidemiologia , Guanina/uso terapêutico , Humanos , Incidência , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Resultado do TratamentoRESUMO
Thymomas can present with a variety of paraneoplastic manifestations, mostly of autoimmune origin, including Good's syndrome when there is associated hypogammaglobulinemia. Although pure red cell aplasia is a recognised complication of thymoma, selective white cell aplasia is very rare, particularly in Good's syndrome. Lethal opportunistic infections are a feature of Good's syndrome, usually occurring in those patients with associated severe T lymphocyte defects. Although the cryptococcus is a recognised fungal pathogen in patients with other causes of CD4+ T cell lymphopenia, surprisingly this complication has not been reported in patients with Good's syndrome. We now describe a 70 year old man with Good's syndrome and pure white cell aplasia who presented with disseminated cryptococcosis, and provide an up-to-date review of the relevant literature. Despite meningeal involvement our patient recovered after combined treatment with intravenous globulin, granulocyte stimulating growth, corticosteroids and antifungal therapy.
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Criptococose/complicações , Leucopenia/etiologia , Timoma/complicações , Neoplasias do Timo/complicações , Idoso , Biópsia , Medula Óssea/patologia , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Feminino , Humanos , Leucopenia/diagnóstico , Timoma/diagnóstico , Timoma/cirurgia , Neoplasias do Timo/diagnóstico , Neoplasias do Timo/cirurgiaRESUMO
INTRODUCTION: Current pathogenetic aspects on HIV infection highlight the importance of a chronic immune activation ultimately leading to T lymphocyte homeostasis disruption and immune deregulation associated with disease manifestations and progression. It is widely accepted that this continuous immune activation in HIV infection is principally driven by the phenomenon of pathological microbial translocation (MT). METHODS: Review of the literature on the role of intestinal barrier dysfunction in HIV infection, with emphasis on the implicated pathophysiological mechanisms, clinical implications and potentially effective therapeutic interventions. FINDINGS: MT in HIV infection is promoted by a multifactorial disruption of all major levels comprising the intestinal barrier defense. Specifically, HIV infection disrupts the integrity of the intestinal biological (quantitative and qualitative alterations of gut microecology, overgrowth of pathogenic bacteria), immune (depletion of CD4(+) T cells, especially Th17 cells, increased CD4+ FoxP3+ Tregs, decreased mucosal macrophages phagocytic capacity, development of intestinal proinflammatory milieu) and mechanical barrier (enterocytes' apoptosis, disruption of tight junctions). Intestinal barrier dysfunction allows the passage of microbes and immunostimulatory bioproducts from the gut lumen first in the lamina propria and thereafter in the systemic circulation, thus continuously promoting a local and systemic inflammatory response. This chronic immune activation is associated with HIV disease progression, suboptimal response to HAART and development of non-AIDS comorbidities. CONCLUSIONS: We have reached a point where the effective control of HIV viremia by HAART should be combined with emerging pharmacological approaches aiming at the restoration of the intestinal barrier, targeting its diverse levels of structure and function. Elimination of the MT phenomenon would mitigate its effect on immune homeostasis, which might improve the prognosis of the HIV-infected patient in terms of morbidity and mortality.
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Infecções por HIV/fisiopatologia , Enteropatias/virologia , Intestinos/fisiopatologia , Translocação Bacteriana , Infecções por HIV/tratamento farmacológico , Infecções por HIV/microbiologia , Infecções por HIV/virologia , Humanos , Absorção Intestinal , Enteropatias/microbiologia , Enteropatias/fisiopatologia , Intestinos/microbiologia , Intestinos/virologia , PermeabilidadeRESUMO
Introduction: This study investigated the distribution pattern of tenascin-C and syndecan-1 in the dental mesenchyme during root development of immature swine teeth in order to define the differentiation dynamics of both pulp tissue progenitors and apical papilla cells, as well as to assess the adequacy criticize of the apical papilla to induce dentin-pulp regeneration. Methods: Three 7-month-old miniature swine were used in this study. A total of 12 teeth, including two immature permanent incisors and two premolar teeth of each case, were extracted and processed for histological and immunohistochemical analysis. Different populations of mesenchymal cells located at the root apex were morphologically evaluated in hematoxylin-eosin serial sections. Additionally, the distribution patterns of tenascin-C and syndecan-1 were assessed immunohistochemically. Results: Syndecan-1 was strongly expressed in the dental pulp, particularly along the odontoblasts of the root and the newly deposited predentin layer. Tenascin-C was intensely expressed in the dental pulp. The apical papilla and dental follicle showed no expression of either molecule. Conclusions: Cell differentiation potential in the developing swine apex is progressively restricted to the newly formed dental pulp, whereas phenotypic expression of apical papilla cells remains undetermined unless the new microenvironment triggers cell differentiation towards the odontoblastic lineage.
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The aim of the present study was to determine the prevalence of Legionella spp. in water systems of hospitals and hotels located in South Western Greece, to study the molecular epidemiology of the isolated strains and their possible association with bacterial contamination (total count and Pseudomonas aeruginosa), the water pH, and temperature. A prevalence survey for Legionella spp. by culturing techniques in water distribution systems of eight hospitals and nine hotels occurred in South Western Greece. Water sampling and microbiological analysis were carried out following the ISO methods. Legionella pneumophila was detected in 33% and 36% of the distribution systems of hospitals and hotels, respectively. Our survey results suggest a frequent prevalence of elevated concentrations of Legionella spp. in water systems of hospitals and hotels. Our investigation has confirmed the need to regularly monitor the microbiological condition of water systems in hospitals and hotels.
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Água Potável/microbiologia , Legionella/genética , Temperatura Baixa , Contagem de Colônia Microbiana , Água Potável/química , Grécia , Hospitais , Temperatura Alta , Habitação , Legionella/classificação , Legionella/isolamento & purificação , Legionella pneumophila/classificação , Legionella pneumophila/genética , Legionella pneumophila/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , SorotipagemRESUMO
BACKGROUND AND PURPOSE: Inflammatory cytokines are involved in the systemic inflammation, which precedes an ischaemic stroke (IS), and also participate into brain ischaemia-reperfusion injury. We sought to investigate whether functional polymorphisms of two anti-inflammatory molecules, interleukin (IL)4-589C>T and IL10-1082G>A, might be associated with the occurrence, clinical course and functional outcome of an acute IS. METHODS: We genotyped 290 subjects (145 consecutive IS cases and 145 age- and sex-matched controls) using a real-time PCR technology, prototypically designed for these mutations. Patients were evaluated with the Scandinavian Stroke Scale, and definitions of severity grouping and stroke progression were applied based on international agreements. Follow-up on months 1, 3, and 6 included registration of disease relapses, deaths and functional outcome measured by the Barthel Index. RESULTS: IL4-589 and IL10-1082 genotypes did not significantly differ between cases and controls. The presence of IL4-589 T allele was associated with total IS recurrences [OR (95% CI) = 3.34 (1.18-9.45)], adjusted for age, sex and conventional risk factors. IL10-1082 GG genotype was found to significantly predict early stroke progression [OR (95% CI) = 3.72 (1.28-10.76)] and functional outcome by months 1 and 3 [OR (95% CI) = 5.03 (1.15-21.94) and 5.84 (1.07-31.85), respectively], after further corrections for stroke severity and TOAST categories. CONCLUSIONS: The functional IL4-589C>T and IL10-1082G>A polymorphisms seem not to be associated with occurrence of an IS, but may predict IS relapses, progressing strokes and functional outcome, independently of conventional risk factors. Our results merit further confirmation in future studies.
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Predisposição Genética para Doença , Interleucina-10/genética , Interleucina-4/genética , Polimorfismo de Nucleotídeo Único , Recuperação de Função Fisiológica/genética , Acidente Vascular Cerebral/genética , Idoso , Isquemia Encefálica/genética , Isquemia Encefálica/imunologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Acidente Vascular Cerebral/imunologiaRESUMO
BACKGROUND AND AIM: The phenotypic expression of COPD consists of pulmonary emphysema and chronic bronchitis. An imprecise phenotypic definition may result in inconsistencies among genetic studies regarding COPD pathogenesis. Endothelin-1 gene polymorphisms have been linked to increased susceptibility of COPD development. The present study examined the involvement of +138 insA/delA and G198T ET-1 polymorphisms with emphysematous and bronchitic COPD phenotypes. METHODS: In order to narrow down the phenotypic choices to either COPD-associated pulmonary emphysema or chronic bronchitis, a DLCO < 60% predicted threshold was chosen as an indicator of severe emphysema. 116 COPD smokers and 74 non-related, non-COPD smokers were evaluated. RESULTS: Statistical analysis showed that the 4A allele of the +138insA/delA SNP and the 4A:T haplotype were associated predominantly with a chronic bronchitis phenotype, whereas the TT genotype of the G198T SNP was found to be protective from emphysema development. CONCLUSIONS: The presence of both the 4A and T allele seems to modify the final expression of COPD towards a chronic bronchitis phenotype, since the G:3A haplotype was associated with a predominantly emphysematous phenotype in our study.
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Endotelina-1/genética , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/genética , População Branca/genética , Volume Expiratório Forçado , Genética Populacional , Genótipo , Haplótipos , Humanos , FenótipoRESUMO
Healthcare workers (HCWs) have been recognized as a high-risk group for infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This study estimated their risk of infection based on hospital characteristics. Factors significantly associated with increased risk for SARS-CoV-2 infection were: working in a non-referral hospital compared with a coronavirus disease 2019 (COVID-19) referral hospital, working in a hospital with a high number of employees, and working in a hospital with an increased number of patients with COVID-19. This study revealed gaps in infection control in the non-referral hospitals. There is an urgent need for continuous training in infection control practices. Compliance of HCWs with the use of personal protective equipment should also be addressed.
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COVID-19/epidemiologia , COVID-19/etiologia , Pessoal de Saúde , Hospitais/estatística & dados numéricos , Controle de Infecções/normas , Atenção à Saúde , Grécia/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional , Equipamento de Proteção Individual , Fatores de RiscoRESUMO
Red blood cell (RBC) deformability is a major determinant of the ability of the RBC to pass repeatedly through the microcirculation. A decrease in RBC deformability leads to tissue perfusion and organ dysfunction. The purpose of this study was to measure the rigidity of RBCs from human immunodeficiency virus (HIV) seropositive individuals and investigate its relation to immune status and viral load. A filtration method based on the initial flow rate principle was used to determine the index of rigidity (IR) of 53 samples from HIV patients and 53 healthy individuals. The mean IR was significantly increased in patients with HIV compared to healthy individuals (P < 0.01). IR was inversely correlated with current CD4+ T-lymphocyte counts (P < 0.0001). High CD4 cell counts (>200 cells/microl) are related to low IR values, independently of the viral load (VL). No differences in rigidity were noted between the VL groups, although there was a trend towards an increased IR in patients with high VL within the group of CD4<200. RBC deformability is decreased in HIV disease, in a degree mainly related to CD4 depletion. Further studies are needed to elucidate the underlying mechanisms and the role of VL in highly immunocompromised HIV patients.
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Elasticidade , Eritrócitos/citologia , Eritrócitos/fisiologia , Infecções por HIV/patologia , Contagem de Linfócito CD4 , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Carga ViralRESUMO
AIM: To use the fluid transport model to evaluate the ex vivo short- and long-term microleakage along root canals filled with Gutta-flow or AH-Plus using the cold lateral compaction technique. METHODOLOGY: A total of 38 single-rooted human teeth were used for the assessment of microleakage. The crowns of the teeth were sectioned below their cemento-enamel junctions to adjust the length of the roots to approximately 15 mm. The root canals were instrumented using the step-back technique and filled using cold lateral condensation. The sealer employed was either Gutta-flow (Group A) or AH-Plus (Group B). Microleakage along the root canals was evaluated using a fluid transport model after periods of 1 week and 3 months. RESULTS: The microleakage values (microL h(-1)) for group A were 0.36 +/- 0.33 at 1 week and 0.41 +/- 0.36 at 3 months. Group B showed mean microleakage values 0.2 +/- 0.31 at 1 week and 0.28 +/- 0.38 at 3 months. Statistical analysis indicated no significant differences (P > 0.05) between the two groups after either 1 week or 3 months. CONCLUSIONS: There was no significant difference between AH-plus and Gutta-flow in terms of sealing ability.
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Colagem Dentária , Infiltração Dentária/classificação , Dimetilpolisiloxanos/química , Resinas Epóxi/química , Guta-Percha/química , Materiais Restauradores do Canal Radicular/química , Cavidade Pulpar/patologia , Combinação de Medicamentos , Ácido Edético/química , Humanos , Umidade , Teste de Materiais , Pressão , Irrigantes do Canal Radicular/química , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Hipoclorito de Sódio/química , Propriedades de Superfície , Temperatura , Fatores de Tempo , Água/químicaRESUMO
AIM: To evaluate the effect of root canal taper on irrigant flow inside a prepared root canal during final irrigation with a syringe and two types of needles, using a Computational Fluid Dynamics (CFD) model. METHODOLOGY: A validated CFD model was used to simulate irrigant flow from either a side-vented or a flat 30G needle positioned inside size 30, .02 taper, 30, .04, 30, .06, ProTaper F3 or size 60, .02 taper root canals, at 3 mm short of working length (WL). Velocity, pressure and shear stress in the root canal were evaluated. RESULTS: The side-vented needle could not achieve irrigant replacement to the WL in any of the cases. Significant irrigant replacement was evident further than 2 mm apically to the tip of the flat needle in the size 30, .06 taper, F3 and size 60, .02 taper canal. A wider distribution of wall shear stress was noted as the canal taper increased but the maximum shear stress decreased. The flat needle led to higher mean pressure at the apical foramen. Both needles showed a similar gradual decrease in apical pressure as the taper increased, but the least pressure was calculated in the size 60, .02 taper canal. CONCLUSIONS: An increase in root canal taper improved irrigant replacement and wall shear stress whilst reducing the risk for irrigant extrusion. Irrigant flow in a minimally tapered root canal with a large apical preparation size also improved irrigant replacement and wall shear stress and reduced the risk for irrigant extrusion, compared to the tapered root canals with a smaller apical preparation size.
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Biologia Computacional , Cavidade Pulpar/patologia , Hidrodinâmica , Modelos Biológicos , Irrigantes do Canal Radicular/química , Preparo de Canal Radicular/métodos , Desenho de Equipamento , Humanos , Agulhas , Pressão , Reologia , Preparo de Canal Radicular/instrumentação , Estresse Mecânico , Propriedades de Superfície , Seringas , Ápice Dentário/patologiaRESUMO
AIM: To evaluate the effect of apical preparation size on irrigant flow inside a root canal during final irrigation with a syringe and two different needles types, using a Computational Fluid Dynamics (CFD) model. METHODOLOGY: A validated CFD model was used to simulate the irrigant flow from either a side-vented or a flat 30G needle positioned inside root canals having sizes of 25, 35, 45 and 55, all with a .06 taper, at 3 mm short of working length (WL). Velocity, pressure and shear stress in the root canal were evaluated. RESULTS: Different preparation sizes resulted in minor differences in the flow pattern in the apical root canal. Major differences were observed between the two needle types. The side-vented needle could not achieve irrigant replacement to the WL even in a size 55, .06 taper root canal. Significant irrigant replacement was evident almost to the WL in size 35, 45 and 55, .06 taper root canals with the flat needle. The maximum shear stress decreased as the preparation size increased. The flat needle developed higher mean pressure at the apical foramen. Both needles led to a similar gradual decrease in apical pressure as the preparation size increased. CONCLUSIONS: Apical preparation size affected irrigant replacement, the shear stress on the canal wall and the pressure at the apical foramen. Root canal enlargement to sizes larger than 25 appeared to improve the performance of syringe irrigation. Adequate space between the needle and the canal wall should be ensured to allow for an effective reverse flow of the irrigant towards the canal orifice.
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Biologia Computacional , Cavidade Pulpar/patologia , Hidrodinâmica , Modelos Biológicos , Irrigantes do Canal Radicular/química , Preparo de Canal Radicular/métodos , Ápice Dentário/patologia , Algoritmos , Simulação por Computador , Desenho de Equipamento , Humanos , Agulhas , Pressão , Reologia , Preparo de Canal Radicular/instrumentação , Estresse Mecânico , Propriedades de Superfície , Seringas , Fatores de TempoRESUMO
AIMS: The aim of the study was to investigate the association between type-2 diabetes mellitus, other underlying diseases and obesity with the outcomes of critically ill Covid-19 patients in Greece. METHODS: In this retrospective observational multi-centre study, data and outcomes of 90 RNA 2109-nCoV confirmed critically ill patients from 8 hospitals throughout Greece, were analysed. All reported information stand through April 13th 2020. RESULTS: The median age of the patients was 65.5 (IQR 56-73), majority were male (80%) and obesity was present in 34.4% of patients most prevalent to younger than 55 years. Hypertension was the prevailing comorbidity (50%), followed by cardiovascular diseases (21.1%) and type-2 diabetes (18.9%). At admission, common symptoms duration had a median of 8 (IQR 5-11) days. A 13.3% of the patients were discharged, 53.4% were still in the ICUs and 28.9% deceased who were hospitalised for fewer days than the survivors [6 (IQR 3-9) vs. 9 (IQR 7-14.5) respectively]. Aging was not a risk factor but diabetes deteriorates the outcomes. Obesity poses a suggestive burden as it was more notable in deceased versus survivors. CONCLUSIONS: Type 2 diabetes and obesity may have contributed to disease severity and mortality in COVID-19 critically ill patients in Greece.