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Removal of pathogenic viruses from water resources is critically important for sanitation and public health. Nanotechnology is a promising technology for virus inactivation. In this paper, the effects of titanium dioxide (TiO2) anatase nanoparticles (NPs) on human adenovirus type 35 (HAdV-35) removal under static and dynamic (with agitation) batch conditions were comprehensively studied. Batch experiments were performed at room temperature (25 °C) with and without ambient light using three different initial virus concentrations. The virus inactivation experimental data were satisfactorily fitted with a pseudo-first-order expression with a time-dependent rate coefficient. The experimental results demonstrated that HAdV-35 sorption onto TiO2 NPs was favored with agitation under both ambient light and dark conditions. However, no distinct relationships between virus initial concentration and removal efficiency could be established from the experimental data.
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Adenovirus Humanos , Nanopartículas , Titanio , Inactivación de Virus , Titanio/química , Titanio/farmacología , Adenovirus Humanos/efectos de los fármacos , Adenovirus Humanos/química , Adenovirus Humanos/fisiología , Adenovirus Humanos/genética , Adsorción , Humanos , Inactivación de Virus/efectos de los fármacos , Nanopartículas/química , Purificación del Agua/métodos , Purificación del Agua/instrumentación , CinéticaRESUMEN
Exposure to wildfire smoke and dust can severely affect air quality and health. Although particulate matter (PM) levels and exposure are well-established metrics linking to health outcomes, they do not consider differences in particle toxicity or deposition location in the respiratory tract (RT). Usage of the oxidative potential (OP) exposure may further shape our understanding on how different pollution events impact health. Towards this goal, we estimate the aerosol deposition rates, OP and resulting OP deposition rates in the RT for a typical adult Caucasian male residing in Athens, Greece. We focus on a period when African dust (1-3 of August 2021) and severe wildfires at the northern part of the Attika peninsula and the Evia island, Greece (4-18 of August 2021) affected air quality in Athens. During these periods, the aerosol levels increased twofold leading to exceedances of the World Health Organization (WHO) [15(5) µg m-3] PM10 (PM2.5) air quality standard by almost 100 %. We show that the OP exposure is 1.5-times larger during the wildfire smoke events than during the dust intrusion, even if the latter was present in higher mass loads - because wildfire smoke has a higher specific OP than dust. This result carries two important implications: OP exposure should be synergistically used with other metrics - such as PM levels - to efficiently link aerosol exposure with the resulting health effects, and, certain sources of air pollution (in our case, exposure to biomass burning smoke) may need to be preferentially controlled, whenever possible, owing to their disproportionate contribution to OP exposure and ability to penetrate deeper into the human RT.
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Contaminantes Atmosféricos , Contaminación del Aire , Incendios Forestales , Adulto , Humanos , Masculino , Polvo , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Humo/efectos adversos , Sistema Respiratorio/química , Estrés OxidativoRESUMEN
INTRODUCTION: The aim of this prospective case series was to assess the clinical and radiographic outcome of partial pulpotomy in caries-exposed symptomatic, vital, immature, permanent molars. METHODS: Thirty-four immature molars with deep caries and symptoms of irreversible pulpitis were treated by partial pulpotomy and ProRoot MTA as a capping material. After complete caries removal, the inflamed part of the pulp was removed. Complete hemostasis was achieved using a sterile cotton pellet moist initially with sodium hypochlorite 1.5% and then with sterile saline. ProRoot MTA (Dentsply Sirona, Charlotte, NC) was placed as a capping material onto the remaining pulp tissue. The cavity was sealed using a light-curing resin-modified Ca(OH)2 cavity liner, and patients were referred to a pediatric dentist for permanent restoration. Descriptive statistics and cross tabulations were performed including variables examined before, during, and after the procedure. RESULTS: All examined teeth presented a favorable clinical and radiographic outcome with normal periapical tissues, complete apical closure, and formation of a dentinal bridge beneath the capping material. Signs of partial pulp chamber calcification were only detected in 2 cases. Postoperatively, most patients did not report any pain (23/34, 67.7%), whereas the rest reported minor intensity pain (11/34, 32.3) and the use of analgesic or anti-inflammatory drugs only for 1 day (10/34, 29.4%). CONCLUSIONS: Partial pulpotomy seems to provide a universally successful outcome when managing symptomatic vital immature teeth with no signs of complications and completion of apical closure. It could be a viable treatment of choice in cases of caries-exposed vital immature teeth with symptoms of irreversible pulpitis.
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Caries Dental , Pulpitis , Niño , Humanos , Pulpotomía/métodos , Pulpitis/cirugía , Pulpitis/tratamiento farmacológico , Compuestos de Calcio/uso terapéutico , Silicatos/uso terapéutico , Dentición Permanente , Caries Dental/cirugía , Resultado del Tratamiento , Óxidos/uso terapéutico , Combinación de MedicamentosRESUMEN
AIM: To assess the clinical and radiographic outcome of partial pulpotomy by comparing MTA Angelus and Total Fill BC, as pulpotomy agents, in mature teeth with deep caries and symptoms indicative of irreversible pulpitis. METHODOLOGY: The study was designed as a parallel-two arm, double-blind, randomized superiority clinical trial registered at www. CLINICALTRIALS: gov (NCT04870398). Symptomatic mature permanent teeth with deep caries fulfilling the inclusion criteria were randomly treated using either MTA Angelus or Total Fill BC. A partial pulpotomy was performed and following complete haemostasis, the capping material was placed over the remaining pulp tissue and a postoperative periapical radiograph was taken. Clinical and radiographic follow-up evaluation was performed for a median time of 2 years, whereas levels of pain intensity were evaluated preoperatively and for 7 days after intervention using Visual Analogue Scale. For the primary outcome (failure/success of treatment), the Kaplan-Meier survival curves for the capping materials were plotted and a log-rank test for equality of survivor functions was applied. A multivariable random effects Cox Regression model was also applied. For the secondary outcome (postoperatively reported pain), a multivariable mixed effects ordinal logistic regression was structured. RESULTS: One hundred and thirty-seven teeth in 123 patients underwent partial pulpotomy using randomly either MTA Angelus (N = 74) or Total Fill BC (n = 63). The percentage failure for MTA Angelus and Total Fill BC was 10.8% (8/74) and 17.5% (11/63), respectively, but the difference was not statistically significant [adjusted HR: 1.83; 95% confidence interval (CI): 0.68, 4.91; p = .23]. Weak evidence was found that secondary caries involvement may impose a 3.54 times greater hazard for treatment failure (adjusted HR: 3.54; 95% CI: 1.00, 12.51; p = .05). For each passing minute of procedural bleeding control, there was also a 57% higher hazard for treatment failure (adjusted HR: 1.57; 95% CI: 0.99, 2.48; p = .05). The odds for higher postoperative pain were 4.73 times greater for the Total Fill BC compared to MTA Angelus (adjusted OR: 4.73; 95% CI: 2.31, 9.66; p < .001). CONCLUSIONS: Both materials exhibited similar and favourable outcome rates after partial pulpotomy in teeth with deep caries and symptoms of irreversible pulpitis. Total Fill BC was associated with a higher level of postoperative pain intensities.
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Pulpitis , Humanos , Pulpitis/cirugía , Pulpitis/tratamiento farmacológico , Pulpotomía , Compuestos de Calcio/uso terapéutico , Silicatos/uso terapéutico , Óxidos/uso terapéutico , Resultado del Tratamiento , Combinación de Medicamentos , Compuestos de Aluminio/uso terapéuticoRESUMEN
A growing body of evidence suggests that RNA interference (RNAi) plays a pivotal role in the communication between plants and pathogenic fungi, where a bi-directional trans-kingdom RNAi is established to the advantage of either the host or the pathogen. Similar mechanisms acting during plant association with non-pathogenic symbiotic microorganisms have been elusive to this date. To determine whether root endophytes can induce systemic RNAi responses to their host plants, we designed an experimental reporter-based system consisting of the root-restricted, beneficial fungal endophyte, Fusarium solani strain K (FsK) and its host Nicotiana benthamiana. Since not all fungi encode the RNAi machinery, we first needed to validate that FsK does so, by identifying its core RNAi enzymes (2 Dicer-like genes, 2 Argonautes and 4 RNA-dependent RNA polymerases) and by showing its susceptibility to in vitro RNAi upon exogenous application of double stranded RNAs (dsRNAs). Upon establishing this, we transformed FsK with a hairpin RNA (hpRNA) construct designed to target a reporter gene in its host N. benthamiana. The hpRNA was processed by FsK RNAi machinery predominantly into 21-24-nt small RNAs that triggered RNA silencing but not DNA methylation in the fungal hyphae. Importantly, when the hpRNA-expressing FsK was used to inoculate N. benthamiana, systemic RNA silencing and DNA methylation of the host reporter gene was recorded. Our data suggest that RNAi signals can be translocated by root endophytes to their hosts and can modulate gene expression during mutualism, which may be translated to beneficial phenotypes.
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Endófitos , ARN Bicatenario , Interferencia de ARN , Endófitos/genética , Endófitos/metabolismo , Genes Reporteros , Metilación de ADN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismoRESUMEN
The increased mass production and application of engineered nanomaterials (ENMs) have resulted in the release of nanoparticles (NPs) in the environment, raising uncertainties regarding their environmental impacts. This study examines the effect of graphene oxide (GO) and titanium dioxide (TiO2) NPs on the inactivation of the three model bacteria originated by mammalians including humans: Escherichia (E.) coli, Enterococcus (E.) faecalis, and Staphylococcus (S.) aureus. A series of dynamic batch experiments were conducted at constant room temperature (22 °C) in order to examine the inactivation of co-existing bacteria by NPs, in the presence and absence of quartz sand. The inactivation experimental data were satisfactorily fitted with a pseudo-first order expression with a time dependent rate coefficient. The inactivation of E. coli and S. aureus was shown to increase in the co-presence of GO or TiO2 NPs and quartz sand comparing with the presence of GO or TiO2 NPs alone. For E. faecalis, no clear trend was observed. Moreover, quartz sand was shown to affect inactivation of bacteria by GO and TiO2 NPs. Among the bacteria examined, the highest inactivation rates were observed for S. aureus.
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Nanopartículas , Cuarzo , Escherichia coli , Grafito , Humanos , Arena , Staphylococcus aureus , TitanioRESUMEN
BACKGROUND/AIM: Greek dentists are facing a new era of a globally continuous effort to improve the first-aid management and long-term treatment outcome of traumatic dental injuries (TDI). In Greece, where the basic and clinical research in the field of dental trauma has been limited until recently, assessing the attitudes and therapeutic strategies of Greek dentists for dental trauma is of great importance. The aim of this study was to evaluate the knowledge attitudes and therapeutic approaches of Greek dentists in different clinical scenarios of TDI. MATERIALS AND METHODS: A cross-sectional study was conducted among 448 dentists. A questionnaire-based survey of demographic characteristics, attitudes, and a scenario-based knowledge test, of TDI, which was used to formulate a "Dental Trauma Knowledge Score" with a 0-8 score range, was administered. Mann-Whitney U tests (for two categories variables) and Kruskal-Wallis tests (for more than two categories variables) were performed. RESULTS: The median knowledge score was 5.0 (IQR: 4-7), a level considered as "Acceptable." Knowledge scores were found to significantly differ by age group, with the younger dentists presenting the highest scores. Dentists with a self-evaluation as "Acceptable" had significantly higher scores. Most of the dentists would refer for CBCT in severe trauma cases. A significant association was found between younger ages and on awareness of the mobile application ToothSOS. Female dentists had significantly higher scores compared to males when asked about avulsion management. CONCLUSION: An acceptable level of knowledge on TDI management was revealed among dentists in Greece. Higher knowledge scores were observed among younger dentists.
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Traumatismos de los Dientes , Estudios Transversales , Odontólogos , Femenino , Grecia , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Encuestas y Cuestionarios , Traumatismos de los Dientes/terapiaRESUMEN
â¢This work describes a protocol for hairy root transformation of the medicinal crop legume fenugreek (Trigonella foenum-graecum L.). Hairy root plant transformation mediated by Agrobacterium rhizogenes is an established method for the rapid genetic transformation of various dicotyledonous plants. We have adapted a hairy root transformation protocol from the model legume Medicago truncatula for use in this metabolically rich non-model crop legume. Considering the great variety and abundance of phytochemicals in fenugreek and its established use in traditional medicine, we aim for this method to become a resource for metabolic pathway identification and for production of valuable specialised metabolites via metabolic engineering approaches.â¢Development rapid transformation (2.5-3 weeks) of fenugreek roots via A. rhizogenes.â¢Marker gene cassette with suitable promoter for visual detection of transformed fenugreek roots.
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The development of genetic transformation methods is critical for enabling the thorough characterization of an organism and is a key step in exploiting any species as a platform for synthetic biology and metabolic engineering approaches. In this work we describe the development of an Agrobacterium rhizogenes-mediated hairy root transformation protocol for the crop and medicinal legume fenugreek (Trigonella foenum-graecum). Fenugreek has a rich and diverse content in bioactive specialised metabolites, notably diosgenin, which is a common precursor for synthetic human hormone production. This makes fenugreek a prime target for identification and engineering of specific biosynthetic pathways for the production of triterpene and steroidal saponins, phenolics, and galactomanans. Through this transformation protocol, we identified a suitable promoter for robust transgene expression in fenugreek. Finally, we establish the proof of principle for the utility of the fenugreek system for metabolic engineering programs, by heterologous expression of known triterpene saponin biosynthesis regulators from the related legume Medicago truncatula in fenugreek hairy roots.
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Ingeniería Metabólica , Redes y Vías Metabólicas , Trigonella , Agrobacterium , Diosgenina , Humanos , Raíces de Plantas , Saponinas , Transformación Genética , Trigonella/genética , Trigonella/metabolismoRESUMEN
This study examines the effect of graphene oxide (GO) nanoparticles (NPs) on the transport (individual species) and cotransport (simultaneous transport) of three biocolloids (Escherichia (E.) coli, Enterococcus (E.) faecalis and Staphylococcus (S.) aureus) in water saturated porous media. Flowthrough experiments were performed in 30-cm long laboratory columns packed with quartz sand. All of the experiments were conducted at room temperature (22⯰C), pHâ¯=â¯7, and ionic strength Isâ¯=â¯2â¯mM. The results from the cotransport experiments indicated that the mass recovery values for all biocolloids, calculated based on total biocolloid concentration in the effluent, were reduced in the presence of GO NPs. The strains E. coli and E. faecalis were shown to be more vulnerable to GO NPs than S. aureus. Temporal moments of the breakthrough concentrations suggested that the presence of GO NPs significantly influenced the fate and transport of the three biocolloids. Extended DLVO theory was used to quantify the various interaction energy profiles, based on electrokinetic and hydrodynamic measurements.
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Enterococcus faecalis/química , Escherichia coli/química , Grafito/química , Nanopartículas/química , Staphylococcus aureus/química , Coloides/química , Tamaño de la Partícula , Porosidad , Propiedades de SuperficieRESUMEN
Glycogen synthase kinase/SHAGGY-like kinases (SKs) are a highly conserved family of signaling proteins that participate in many developmental, cell-differentiation, and metabolic signaling pathways in plants and animals. Here, we investigate the involvement of SKs in legume nodulation, a process requiring the integration of multiple signaling pathways. We describe a group of SKs in the model legume Lotus japonicus (LSKs), two of which respond to inoculation with the symbiotic nitrogen-fixing bacterium Mesorhizobium loti. RNAi knock-down plants and an insertion mutant for one of these genes, LSK1, display increased nodulation. Ηairy-root lines overexpressing LSK1 form only marginally fewer mature nodules compared with controls. The expression levels of genes involved in the autoregulation of nodulation (AON) mechanism are affected in LSK1 knock-down plants at low nitrate levels, both at early and late stages of nodulation. At higher levels of nitrate, these same plants show the opposite expression pattern of AON-related genes and lose the hypernodulation phenotype. Our findings reveal an additional role for the versatile SK gene family in integrating the signaling pathways governing legume nodulation, and pave the way for further study of their functions in legumes.
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Lotus/genética , Lotus/metabolismo , Nodulación de la Raíz de la Planta/genética , Nodulación de la Raíz de la Planta/fisiología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Técnicas de Silenciamiento del Gen , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Mesorhizobium/fisiología , Nitratos/metabolismo , Bacterias Fijadoras de Nitrógeno , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Serina-Treonina Quinasas/clasificación , Interferencia de ARN , Rhizobium/metabolismo , Nódulos de las Raíces de las Plantas , SimbiosisRESUMEN
BACKGROUND: Natural history, predisposing factors to an unfavourable outcome and the effect of various therapeutic regimens were evaluated in a cohort of 457 patients with immunoglobulin A nephropathy (IgAN) and follow-up of at least 12 months. METHODS: Patients with normal renal function and proteinuria <1 g/24 h as well as those with serum creatinine (SCr) >2.5 mg/dL and/or severe glomerulosclerosis received no treatment. Patients with normal or impaired renal function and proteinuria >1 g/24 h for >6 months received daily oral prednisolone or a 3-day course of intravenous (IV) methylprednisolone followed by oral prednisolone per os every other day or a combination of prednisolone and azathioprine. The clinical outcome was estimated using the primary endpoints of end-stage renal disease and/or doubling of baseline SCr. RESULTS: The overall 10-year renal survival was 90.8%, while end-stage renal disease and doubling of baseline SCr developed in 9.2% and 14.7% of patients, respectively. Risk factors related to the primary endpoints were elevated baseline SCr, arterial hypertension, persistent proteinuria >0.5 g/24 h and severity of tubulointerstial fibrosis. There was no difference in the clinical outcome of patients treated by the two regimens of corticosteroids; nevertheless, remission of proteinuria was more frequent in patients who received IV methylprednisolone (P = 0.000). The combination of prednisolone with azathioprine was not superior to IV methylprednisolone followed by oral prednisolone. Side effects related to immunossuppressive drugs were observed in 12.8% of patients. CONCLUSION: The clinical outcome of patients with IgAN was related to the severity of clinical and histological involvement. The addition of azathioprine to a corticosteroid-based regimen for IgAN does not improve renal outcome.
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BACKGROUND: Fatigue is a common symptom referred by many patients undergoing hemodialysis. Fatigue is associated with poor health-related quality of life (HRQoL) and is an important predictor for survival of hemodialysis patients. AIM: To assess the levels of fatigue and demographic factors affecting it among patients with End Stage Renal Disease undergoing hemodialysis. METHODS: This quantitative study was carried out in two Dialysis Units of Hospitals in Athens Region. Between January 2015 and June 2015, 129 hemodialysis patients completed the Greek Version of the Fatigue Assessment Scale (FAS). Demographic data of patients was recorded. For the statistical analysis IBM SPSS Statistics version 20 was used. RESULTS: The mean FAS score was 24.99. 49 patients (38.0%) were non fatigued, 61 patients (47.3%) were fatigued, and 19 patients (13.7%) were extremely fatigued. Higher levels of fatigue were reported among hemodialysis patients residing in urban areas, in those with low educational level and unemployed. CONCLUSION: The findings of this study can be used in the assessment of fatigue and early identification of high-risk patients (especially of the unemployed, those who occupy with domestic works, those with low educational level and of urban citizens). Use of this knowledge by hemodialysis nurses may lead to a better understanding of the factors of fatigue in ESRD, which in turn may lead to a more effective treatment.
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Fatiga/epidemiología , Fallo Renal Crónico/terapia , Diálisis Renal , Escolaridad , Fatiga/etiología , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Prevalencia , Calidad de Vida , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
The elderly are the most rapidly growing population group in the world. Data collected over a 30-year period have demonstrated the increasing prevalence of hypertension with age. The risk of coronary artery disease, stroke, congestive heart disease, chronic kidney insufficiency and dementia is also increased in this subgroup of hypertensives. Hypertension in the elderly patients represents a management dilemma to cardiovascular specialists and other practioners. During the last years and before the findings of the Systolic Hypertension in Europe Trial were published, the general medical opinion considered not to decrease blood pressure values similarly to other younger patients, in order to avoid possible ischemic events and poor oxygenation of the organs (brain, heart, kidney). The aim of this review article is to highlight the importance of treating hypertension in aged population in order to improve their quality of life and lower the incidence of the cardiovascular complications.
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INTRODUCTION: The purpose of this study was to compare decision-making choices among dentists with different levels of training. METHODS: Scanned periapical radiographs and a leaflet with relevant information of 17 endodontically treated teeth were mailed to 40 undergraduate students, 25 general practitioners, 20 postgraduate students, and 40 endodontists. All teeth were symptom-free. The hypothetical scenario referred to patients who sought treatment for first time and had noncontributory medical history. Five treatment options were given for each situation: (1) Extraction, (2) Surgical Retreatment, (3) Nonsurgical Retreatment, (4) Wait and See, and (5) No Therapy. Statistical analysis was performed by using multinomial logistic regression models. RESULTS: The overall response rate was 70.4%, with endodontists exhibiting the lowest response. The undergraduates gave 4 or 5 treatment solutions for all cases, in contrast to endodontists, who gave 2 or 3 treatment solutions in a percentage of 82%. Nonsurgical Retreatment predominated among the participants' choices. Significant differences were detected in (1) Extraction for postgraduate students (P = .008) and endodontists (P = .001), (2) Surgical Retreatment for general practitioners (P = .002), postgraduate students (P = .002), and endodontists (P = .001), and (3) Wait and See for postgraduate students (P = .023). CONCLUSIONS: Differences in specialty training and experience strongly influence endodontic decision making. Endodontists showed the most consistent agreement among the groups.
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Competencia Clínica , Toma de Decisiones , Tratamiento del Conducto Radicular , Especialidades Odontológicas/educación , Educación de Posgrado en Odontología , Endodoncia/educación , Odontología General , Humanos , Planificación de Atención al Paciente , Radiografía de Mordida Lateral , Retratamiento , Estudiantes de Odontología , Extracción Dental , Diente no Vital/terapiaRESUMEN
OBJECTIVE: To investigate the quality of root canal fillings and coronal restorations in relation to periapical status in a Greek population. METHOD AND MATERIALS: A total of 320 patients who required full-mouth radiographic examination were included. The quality of root canal fillings and the periapical status, as well as the quality of coronal restorations, were assessed by radiographic criteria. Results were analyzed using random effects logistic regression models. RESULTS: Root canals with adequate filling length had a lower incidence of apical periodontitis than root canals with inadequate filling length (51.7% versus 63.4%, P ;= .002). Root-filled canals with adequate coronal restorations showed a lower incidence of apical periodontitis than those with inadequate restorations (47.3% versus 67.4%, P; < .001). When both root filling and coronal restoration were assessed, the incidence of apical periodontitis ranged from 39.2% to 67.6%. CONCLUSION: Quality of root canal treatment, as well as quality of coronal restoration, are strongly associated with the incidence of apical periodontitis.
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Restauración Dental Permanente/estadística & datos numéricos , Enfermedades Periapicales/epidemiología , Obturación del Conducto Radicular/estadística & datos numéricos , Apicectomía/normas , Apicectomía/estadística & datos numéricos , Coronas/normas , Coronas/estadística & datos numéricos , Caries Dental/epidemiología , Adaptación Marginal Dental/normas , Cavidad Pulpar/diagnóstico por imagen , Restauración Dental Permanente/normas , Estudios Epidemiológicos , Grecia/epidemiología , Humanos , Incidencia , Periodontitis Periapical/epidemiología , Pulpotomía/normas , Pulpotomía/estadística & datos numéricos , Radiografía , Materiales de Obturación del Conducto Radicular/normas , Obturación del Conducto Radicular/normasRESUMEN
OBJECTIVE: To evaluate coronal leakage and apical material extrusion of 3 obturation techniques. METHOD AND MATERIALS: The coronal part of 60 freshly extracted human maxillary central incisors was removed, leaving roots 10 mm in length. After instrumentation by hand K-files and smear layer removal, the 60 roots were divided randomly into 3 groups. The roots of each group were obturated using different obturation techniques. The obturation techniques tested were cold lateral condensation, System B, and Thermafil. Leakage measurements were accomplished using fluid filtration methodology. Filling material extrusion was recorded using a yes or no statement. Results were subjected to statistical analysis using chi-square tests. RESULTS: Fluid filtration results revealed no significant differences among the 3 techniques tested 48 hours after obturation (P >.05). Thermafil tended to extrude significantly more material beyond the apex (P <.05). CONCLUSIONS: The 3 obturation techniques are equally effective at sealing the root canals. Thermafil's tendency for slight material extrusion should be considered when obturating canals with insufficient apical constriction.