RESUMO
Oral candidiasis is an opportunistic infection caused by fungi of the genus Candida. Nystatin, fluconazole, and miconazole are the most widely used antifungal drugs in dentistry, but in recent years, they have been shown to be less effective due to the increase in the resistance to antifungal drugs. The growing challenge of antifungal resistance emphasizes the importance of exploring not only alternative strategies in the fight against Candida spp. infections but also supportive treatment for pharmacological treatment for oral candidiasis. This review aims to evaluate and compare the in vitro reports on antifungal efficacy against Candida spp. exhibited by mouthwashes distributed on the European market. The research question was elaborated through the PEO framework recommended by PRISMA 2020. A bibliographic search strategy was developed for the scientific online databases Pubmed and ScienceDirect. According to the eligibility criteria, 21 papers were included in this study over a 27-year period. Mouthwashes containing chlorhexidine digluconate, cetylpyridinium chloride, hexetidine, and fluorine compounds among others, and natural antimicrobials, such as menthol, thymol, eucalyptol, and Glycyrrhiza glabra extracts, have demonstrated antifungal effectiveness. Nonetheless, the methodological variance introduces ambiguity concerning the comparative efficacy of distinct molecules or mouthwash formulations and complicates the evaluation and the comparison of results between studies. Some mouthwashes commercially available in Europe have the potential to be used in anti-Candida therapy and prevention since they have shown antifungal effect.
RESUMO
The rising trend of plastic production in last years and the inadequate disposal of related waste has raised concerns regarding microplastic-related environmental issues. Microplastic particles disperse by means of transport and deposition processes to different ecosystems and enter food chains. In this paper, atmospheric deposition and foliage samples of two species (i.e., Hedera helix and Photinia glabra) were collected and analysed for the quantity and identity of microplastics (MPs). A preliminary methodology to treat foliage samples and subsequently identify MPs using a quantum cascade laser IR spectrophotometer is presented. The treatment of airborne samples involved filtration, mild digestion, concentration, and transfer onto reflective slides whereas that for foliage involved washing, concentration, and transference of putative MPs onto reflective slides. Fibers and fragments were differentiated according to their physical features (size, width, height, etc.) and calculating derived characteristics (namely, circularity and solidity). The preliminary results obtained suggest a good agreement between atmospheric-deposited and foliage-retained MPs, showing the capability of leaves to act as passive samplers for environmental monitoring.
Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Microplásticos , Folhas de Planta , Monitoramento Ambiental/métodos , Microplásticos/análise , Folhas de Planta/química , Poluentes Atmosféricos/análise , Hedera/química , Tamanho da Partícula , Atmosfera/química , Plásticos/análiseRESUMO
Pollution caused by plastics and, in particular, microplastics has become a source of environmental concern for Society. Their ubiquity, with millions of tons of plastic debris spilled in both land and sea, requires efficient technological improvements in the ways residues are collected, handled, characterized and recycled. For reliable decision-making, dependable chemical information is essential to assess both the nature of the plastics found in the environment and their fate. In this work an efficient method to identify the polymeric composition of microplastic fragments is proposed. It combines infrared reflectance spectra and chemometric methods. A breakthrough result is that the models include polymers weathered under both dry (shoreline) and submerged (in sea water) conditions and, hence, they are very promising as a starting point for eventual practical applications. In addition, no spectral processing is required after the initial measurement. SYNOPSIS: This approach to identify microplastics in aquatic environments combines infrared measurements and multivariate data analysis to fight against (micro)plastic pollution.
Assuntos
Plásticos , Poluentes Químicos da Água , Plásticos/análise , Microplásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , AlgoritmosRESUMO
This study identified and quantified microplastics in the Bay of Asunción, Paraguay, and its main tributaries. Surface water samples were sieved in duplicate at six locations using stainless-steel sieves (0.3-4.75 mm range), digested employing the Fenton's reaction (Fe-catalysed H2O2 digestion), and floated using NaCl and NaI. Particles were inspected using a microscope and characterized by IR spectrometry. Microplastics were found in all samples; more abundant (p < 0.05) in water from the bay (13.2 ± 13.4 items·m-3) than from the tributaries (1.0 ± 0.5 items·m-3). Most microplastics were common polymers and their abundance was in the order polypropylene > high-density polyethylene > low-density polyethylene, transparent and white. The results were similar to other regional studies and suggested that their main source was single-use packaging, disposed inadequately due to poor garbage collection.
Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/análise , Água/análise , Baías/química , Paraguai , Peróxido de Hidrogênio , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polietileno/análiseRESUMO
Little is known about the benefits of low-level laser therapy (LLLT) on improvement of stability of dental implants. The aim of this randomized clinical study was to assess the LLLT effect on implants stability by means of resonance frequency analysis (RFA). Thirty implants were distributed bilaterally in the posterior mandible of eight patients. At the experimental side, the implants were submitted to LLLT (830 nm, 86 mW, 92.1 J/cm(2), 0.25 J, 3 s/point, at 20 points), and on the control side, the irradiation was simulated (placebo). The first irradiation was performed in the immediate postoperative period, and it was repeated every 48 h in the first 14 days. The initial implant stability quotient (ISQ) of the implants was measured by means of RFA. New ISQ measurements were made after 10 days, 3, 6, 9, and 12 weeks. The initial ISQ values ranged from 65-84, with a mean of 76, undergoing a significant drop in stability from the 10th day to the 6th week in the irradiated group, and presenting a gradual increase from the 6th to the 12th week. The highest ISQ values were observed on the 10th day in the irradiated group, and the lowest in the 6th week in both groups. Under the conditions of this study, no evidence was found of any effect of LLLT on the stability of the implants when measured by RFA. Since high primary stability and good bone quality are of major relevancy for a rigid bone-implant interface, additional LLLT may have little impact macroscopically.
Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Terapia com Luz de Baixa Intensidade/métodos , Mandíbula/cirurgia , Adulto , Análise do Estresse Dentário , Retenção de Dentadura , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Análise de Intenção de Tratamento , Masculino , Teste de Materiais , Pessoa de Meia-Idade , Osseointegração , Adulto JovemRESUMO
Besides being food and a refuge to marine species, macroalgae are a powerful and renewable economic resource. However, they may introduce microplastics (MPs) in the trophic chain. We developed a reliable analytical method to characterize and quantify MPs in common and edible macroalgae. Several digestion methods and filters, along with various measurement options, were studied. A new enzymatic-oxidative protocol with a unique final filtration was selected and validated with a mixture of 5 commercial macroalgae (Undaria pinnatifida spp, Porphyra spp, Ulva spp, Laminaria ochroleuca and Himanthalia elongate). Further, it was shown that washing the macroalgae to release MPs is suboptimal and the potential adhesion of MPs to macroalgae was evaluated. A filter subsampling strategy that scans 33.64 % of its surface reduced the time required to characterize <70 µm particles and fibres directly on the 47 mm diameter filter using an IR microscope (1 sample/day).
Assuntos
Alga Marinha , Poluentes Químicos da Água , Digestão , Microplásticos , Estresse Oxidativo , Plásticos , Poluentes Químicos da Água/análiseRESUMO
The presence and effects of microplastics in the environment is being continuously studied, so the need for a reliable approach to ascertain the polymer/s constituting them has increased. To characterize them, infrared (IR) spectrometry is commonly applied, either reflectance or attenuated total reflectance (ATR). A common problem when considering field samples is their weathering and biofouling, which modify their spectra. Hence, relying on spectral matching between the unknown spectrum and spectral databases is largely defective. In this paper, the use of IR spectra combined with pattern recognition techniques (principal components analysis, classification and regression trees and support vector classification) is explored first time to identify a collection of typical polymers regardless of their ageing. Results show that it is possible to identify them using a reduced suite of spectral wavenumbers with coherent chemical meaning. The models were validated using two datasets containing artificially weathered polymers and field samples.
Assuntos
Microplásticos , Plásticos , Plásticos/análise , Polímeros , Espectrofotometria Infravermelho/métodos , Tempo (Meteorologia)RESUMO
Societal and environmental concern due to frequent reports of microplastics in fish stomachs raised as they may accumulate along the trophic chain. The request for analysing microplastics in fish stresses two major analytical issues: sample treatment and final characterization. The, so far, workhorse for chemical characterization is infrared spectroscopy which is time-consuming. Here, a quantum cascade laser-based device is used to accelerate the characterization stage. Its novelty poses new challenges for sample processing and particle handling because the unknown particles must be transferred to a reflective slide. In this study, three sample digestion protocols (alkaline-oxidative with H2O2, and alkaline-oxidative with NaClO and enzymatic-oxidative) and three different procedures to transfer the filter cake to reflective slides are compared. A simplified enzymatic-oxidative digestion (validated through an interlaboratory exercise) combined with a Syncore® automatic evaporation system and a Laser Direct Infrared Imaging (LDIR) device is proposed first time as a reliable and relatively fast method to treat gastrointestinal tracts of fish. Analytical recoveries were studied using samples of Scomber scombrus and they were ca. 100% for big -i.e., >500 µm- and ca. 90% for medium -i.e., 200-300 µm- particles and ca. 75% for 10 µm thick fibres.
Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental/métodos , Peixes , Trato Gastrointestinal/química , Peróxido de Hidrogênio , Lasers Semicondutores , Plásticos/análise , Poluentes Químicos da Água/análiseRESUMO
The EU goal to reduce marine plastic litter by ca. 30% by 2020 stressed the need to deploy analytical methods to ascertain the polymeric nature of a residue. Furthermore, as plastics age under natural conditions and usual databases do not include their weathered spectra, (micro)plastics in environmental samples may be unidentified. In this paper, polyamide (nylon) microplastics weathering was monitored because of its ubiquity in household commodities, clothes, fishery items and industry, whose residues end up frequently in the environment. Infrared spectra (ATR and microreflectance) and Scanning Electron Microscopy (SEM) images were collected periodically while exposing nylon to controlled weathering. It was seen that ATR was more sensitive than microreflectance to monitor the structural evolution of polyamide and that the spectra and the surface of weathered microplastics showed remarkable differences with the pristine material, which stresses the need for considering its evolution when identifying microplastics in environmental studies. The evolution of six band ratios related to the chemical evolution of this polymer are presented. SEM images revealed the formation of secondary microplastics at the most advanced weathering stages of polyamide.
Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Nylons , Plásticos , Espectrofotometria Infravermelho , Poluentes Químicos da Água/análiseRESUMO
Microplastics (MPs) affect plankton (a basis of the trophic chain) and planktivorous fish can ingest them through food confusion or by trophic transmission. Consensus to determine MPs in plankton is lacking and, so, three digestion treatments were evaluated: Alkaline (potassium hydroxide) and enzymatic (protease plus lipase) digestions, both combined with a hydrogen peroxide stage; and an oxidative method using a surfactant (sodium dodecyl sulfate) plus hydrogen peroxide. The alkaline method using potassium hydroxide was found to damage polystyrene. MPs were identified with a stereomicroscope and characterized by reflectance infrared microscopy in semi-automatic mode (using dedicated multi-well aluminium plates). Analytical recoveries for polypropylene, polystyrene, polyethylene, polyamide, polyvinyl chloride and polyethylene terephthalate were higher than 75%, 82% and 83% for the alkaline, enzymatic and oxidative treatments, respectively. The enzymatic method was successfully validated in a European interlaboratory exercise and the oxidative method was demonstrated to be a reliable, fast and cheaper alternative.
Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Plâncton , Plásticos , Poliestirenos/análise , Poluentes Químicos da Água/análiseRESUMO
Infrared spectrometry (IR) became a workhorse to characterize microplastics (MPs) worldwide. However, reports on the experimental conditions to measure them decreased alarmingly. As complete, relevant information on the instrumental setup determining IR spectra is crucial for scientific reproducibility, ca. 50% of the papers that reported FTIR to measure MPs were evaluated and it was found that most studies cannot be replicated due to missing experimental details. To ameliorate this, the most critical parameters influencing IR spectra are depicted, their impact when matching a spectrum against databases exemplified, and, following efforts from other scientific fields, a minimum information for publication of IR-related data on MPs characterization (MIPIR-MP) is proposed, along with a brief, simple paragraph to resume the most critical information to be reported. This can be used to improve the worrying figures that point out to a reproducibility crisis in the field, as disclosed by the survey.
Assuntos
Monitoramento Ambiental , Microplásticos , Poluentes Químicos da Água , Plásticos , Reprodutibilidade dos TestesRESUMO
In this study the role of plastic debris as a pollution vector has been evaluated by determining the concentrations of hydrophobic organic contaminants in polymers from three Western Mediterranean coastal areas as well as their potential transfer to seawater. Plastic debris was sampled at three Iberian Peninsula Southeastern beaches, each affected by different predominant anthropogenic activities (tourism, agriculture, urban activities, transport and industry). Plastic debris was characterized by attenuated total reflection Fourier-transform infrared spectrometry. The organic contaminants were extracted from plastics by ultrasonic extraction with methanol and quantified by stir bar sorptive extraction coupled to gas chromatography-mass spectrometry (GC-MS). In two areas, the desorption of these contaminants from plastic debris to seawater during 24â¯h was also evaluated. The contaminant groups considered in this study (polycyclic aromatic hydrocarbons (PAHs), personal care products (PCPs), current use pesticides (CUPs), organochlorinated compounds (OCPs, including polychlorinated biphenyls and organochlorinated pesticides) and plastic additives were found in polymers from the three areas. The most abundant contaminants were plastic additives and PCPs, underlining the relevance of the leaching of plastic components, and urban and tourism activities as typical pollution sources in the coastal areas. In general, large piece-to-piece variability was found for all polymers and areas mainly as a consequence of their different origin, exposition time, use and surface-to-volume ratio. This fact difficulted the visualization of significant differences between polymers or areas, but for CUPs, whose concentrations were significantly higher in Cape Cope than in the other areas due to the influence of close agricultural activities. PCPs and CUPs were desorbed partially in seawater for 24â¯h, particularly the most hydrophilic compounds such as triazines and other CUPs. However, a significant fraction of other contaminants (mainly PAHs) was retained, which suggests they can be transported far away from their origin.
Assuntos
Cosméticos/análise , Monitoramento Ambiental , Praguicidas/análise , Plásticos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Resíduos/análise , Poluentes Químicos da Água/análise , Praias , Água do Mar , EspanhaRESUMO
PURPOSE: The aim of this prospective clinical study was to evaluate the clinical and histomorphometric data of newly formed bone tissue from fresh frozen human allograft in sinus lift surgery. PATIENTS AND METHODS: Thirty-three sinus lift procedures were performed in 20 patients, divided into two groups. The control group (n = 8) received autogenous bone from the mandibular ramus, and the experimental group (n = 12) received fresh frozen bone (FFB) allograft in chips. After 6 months, 52 implants were placed and 50 biopsies were collected for histomorphometric analysis. Cone beam computed tomography scans were performed at preoperative, immediate postoperative, and delayed postoperative time intervals to assess the degree of graft volume loss. RESULTS: There was no statistically significant difference between groups as regards degree of graft volume loss (p = .983), total bone area (p = .191), remaining particles (p = .348), and proportion of active osteoblasts (p = .867). There was a statistically significant difference in the vitality rate between the groups (p = .043). In both groups, all implants were clinically osseointegrated after 4 months. CONCLUSION: FFB allograft was shown to be a feasible substitute for autogenous bone graft in sinus lift surgery.
Assuntos
Transplante Ósseo/métodos , Levantamento do Assoalho do Seio Maxilar/métodos , Adulto , Idoso , Aloenxertos , Biópsia , Brasil , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Mandíbula/transplante , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
PLGA nanoparticles are useful to protect and deliver proteins in a localized or targeted manner, with a long-term systemic delivery pattern intended to last for a period of time, depending on polymer bioerosion and biodegradability. However, the principal concern regarding these carriers is the hydrolytic instability of polymer in aqueous suspension. Freeze-drying is a commonly used method to stabilize nanoparticles, and cryoprotectants may be also used, to even increase its physical stability. The aim of the present work was to analyze the influence of cryoprotectants on nanoparticle stability and porosity after freeze-drying, which may influence protein release and stability. It was verified that freeze-drying significantly increased the number of pores on PLGA-NP surface, being more evident when cryoprotectants are added. The presence of pores is important in a lyophilizate to facilitate its reconstitution in water, although this may have consequences to protein release and stability. The release profile of insulin encapsulated into PLGA-NP showed an initial burst in the first 2 h and a sustained release up to 48 h. After nanoparticles freeze-drying the insulin release increased about 18% in the first 2 h due to the formation of pores, maintaining a sustained release during time. After freeze-drying with cryoprotectants, the amount of insulin released was higher for trehalose and lower for sucrose, glucose, fructose and sorbitol comparatively to freeze-dried PLGA-NP with no cryoprotectant added. Besides the porosity, the ability of cryoprotectants to be adsorbed on the nanoparticles surface may also play an important role on insulin release and stability.
Assuntos
Crioprotetores/química , Sistemas de Liberação de Medicamentos , Insulina/administração & dosagem , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Liofilização , Humanos , Insulina/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanomedicina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade , Proteínas Recombinantes/administração & dosagem , Propriedades de Superfície , Tensoativos/química , Fatores de TempoRESUMO
The aim of this study was to evaluate the ability of the BANA Test to detect different levels of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia or their combinations in subgingival samples at the initial diagnosis and after periodontal therapy. Periodontal sites with probing depths between 5-7 mm and clinical attachment level between 5-10 mm, from 53 subjects with chronic periodontitis, were sampled in four periods: initial diagnosis (T0), immediately (T1), 45 (T2) and 60 days (T3) after scaling and root planing. BANA Test and Checkerboard DNA-DNA hybridization identified red complex species in the subgingival biofilm. In all experimental periods, the highest frequencies of score 2 (Checkerboard DNA-DNA hybridization) for P. gingivalis, T. denticola and T. forsythia were observed when strong enzymatic activity (BANA) was present (p < 0.01). The best agreement was observed at initial diagnosis. The BANA Test sensitivity was 95.54% (T0), 65.18% (T1), 65.22% (T2) and 50.26% (T3). The specificity values were 12.24% (T0), 57.38% (T1), 46.27% (T2) and 53.48% (T3). The BANA Test is more effective for the detection of red complex pathogens when the bacterial levels are high, i.e. in the initial diagnosis of chronic periodontitis.
Assuntos
Benzoilarginina-2-Naftilamida , Doenças Periodontais/diagnóstico , Porphyromonas gingivalis/isolamento & purificação , Treponema denticola/isolamento & purificação , Adulto , Distribuição de Qui-Quadrado , Periodontite Crônica/diagnóstico , Periodontite Crônica/microbiologia , Contagem de Colônia Microbiana , Sondas de DNA , Inquéritos de Saúde Bucal , Placa Dentária/microbiologia , Ensaios Enzimáticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico/métodos , Doenças Periodontais/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de TempoRESUMO
A model to simulate the time evolution of river delta formation process is presented. It is based on the continuity equation for water and sediment flow and a phenomenological sedimentation/erosion law. Different delta types are reproduced by using different parameters and erosion rules. The structures of the calculated patterns are analyzed in space and time and compared with real data patterns. Furthermore, our model is capable of simulating the rich dynamics related to the switching of the mouth of the river delta. The simulation results are then compared with geological records for the Mississippi River.
RESUMO
The aim of this study was to evaluate the ability of the BANA Test to detect different levels of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia or their combinations in subgingival samples at the initial diagnosis and after periodontal therapy. Periodontal sites with probing depths between 5-7 mm and clinical attachment level between 5-10 mm, from 53 subjects with chronic periodontitis, were sampled in four periods: initial diagnosis (T0), immediately (T1), 45 (T2) and 60 days (T3) after scaling and root planing. BANA Test and Checkerboard DNA-DNA hybridization identified red complex species in the subgingival biofilm. In all experimental periods, the highest frequencies of score 2 (Checkerboard DNA-DNA hybridization) for P. gingivalis, T. denticola and T. forsythia were observed when strong enzymatic activity (BANA) was present (p < 0.01). The best agreement was observed at initial diagnosis. The BANA Test sensitivity was 95.54 percent (T0), 65.18 percent (T1), 65.22 percent (T2) and 50.26 percent (T3). The specificity values were 12.24 percent (T0), 57.38 percent (T1), 46.27 percent (T2) and 53.48 percent (T3). The BANA Test is more effective for the detection of red complex pathogens when the bacterial levels are high, i.e. in the initial diagnosis of chronic periodontitis.
Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/diagnóstico , Porphyromonas gingivalis/isolamento & purificação , Treponema denticola/isolamento & purificação , Distribuição de Qui-Quadrado , Contagem de Colônia Microbiana , Periodontite Crônica/diagnóstico , Periodontite Crônica/microbiologia , Inquéritos de Saúde Bucal , Sondas de DNA , Placa Dentária/microbiologia , Ensaios Enzimáticos , Hibridização de Ácido Nucleico/métodos , Doenças Periodontais/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de TempoRESUMO
Las fallas marginales representan una de las causas más frecuentes de fracaso en las restauraciones de composite en el sector posterior. Los niveles de falla marginal presentados por estas restauraciones podrían verse afectados por el tipo de configuración dado a los márgenes cavo-superficiales; no obstante, la información disponible al respecto tiende a ser contradictoria. Determinar la influencia que tiene el diseño de tres tipos de márgenes cavo-superficiales (unión abrupta, bisel corto y bisel cóncavo) en los niveles de deterioro marginal presentados en restauraciones directas de composite realizadas en dientes posteriores sometidos a cargas compresivas. Sesenta dientes posteriores humanos sanos extraídos (30 premolares superiores y 30 terceros molares superiores) fueron distribuidos aleatoriamente en tres grupos, cada uno de los cuales estuvo conformado por 10 premolares y 10 molares. A cada uno de los dientes le fue realizada una cavidad clase I estándar con una configuración distinta de margen cavo-superficial para cada grupo (grupo 1= unión abrupta, grupo 2= bisel corto, grupo 3= bisel cóncavo), para posteriormente ser restaurados con un composite empacable mediante técnica directa. Todos los dientes fueron sometidos a 1500 ciclos térmicos entre 5 y 55ºC para posteriormente aplicarles 4000 ciclos de cargas compresivas cíclicas de 300 kN de fuerza máxima a una frecuencia de 5 Hz. El análisis en video lupa de las superficies oclusales de la muestra no reveló diferencias estadísticas significativas (p= 0,139) en los niveles de falla marginal mostrados por los tres tipos de margen cavo estudiados
Marginal deterioration is one the most frequent composite restoration failures at posterior teeth with chewing function. The type of configuration factor at cavosurface margins could affect marginal deterioration levels; however, available information is somewhat contradictory. To determine the influence of three cavosurface margin preparations (butt-joint, bevelled-edge, and concave bevel -chamfer style-) on marginal degradation found in direct composite restorations applied to posterior teeth under compressive strength. Sixty recently extracted human posterior teeth (30 upper bicuspid teeth and 30 upper third molars) were randomly distributed into three groups, having 10 bicuspid teeth and 10 molar teeth each group. Each tooth had standardized Class I slot cavities and was prepared according to the cavosurface margin preparations above mentioned (group 1=butt-joint, group2=bevelled-edge, group 3=concave bevel); then, it received direct packable composite restoration. All teeth were thermocycled 1500x at 5/55 degrees C, cycled 4000x of compressive loading at a maximum strength of 300kN and a frequency of 5Hz. Video loupe analyses of occlusal surfaces from the study sample did not show statistically significant differences (p=0.139) among the three cavosurface margin preparations studied
Assuntos
Humanos , Dente Pré-Molar , Adaptação Marginal Dentária , Cavidade Pulpar , Dente Molar , Resinas Compostas/uso terapêutico , Ligas Metalo-Cerâmicas/análiseRESUMO
Vários estudos longitudinais têm reportado uma alta taxa de sucesso da utilização de implantes osseointegrados no tratamento reabilitador. Entretanto, outras investigações têm mostrado a perda de implantes osseointegrados por causa de infecções periimplantares ou trauma oclusal. A periimplantite é caracterizada pela presença de reações inflamatórias que afetam o tecido periimplantar sob função. Indivíduos portadores de periimplantes são colonizados por patógenos periodontais como Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum e Treponema denticola, enquanto sítios periimplantares sadios são colonizados por cocos Gram-positivos.
Longitudinal studies have reported a high success rate for rehabilitating treatment through the use of osseointegrated implants. However, other studies have reported osseointegrated implant failure due to peri-implant infections or occlusal overload. Peri-implantitis is characterized by the presence of inflammatory reactions that affect the peri-implant tissue under loading. Subjects with peri-implantitis harbor periodontal pathogens such as Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum and Treponema denticola while healthy peri-implant sites harbor cocos Gram-positives.
Assuntos
Doenças Periodontais , Implantes Dentários , MicrobiologiaRESUMO
Os autores analisam a experiencia global do servico em 97 pacientes consecutivos e nao selecionados submetidos a 98 aneurismectomias nos ultimos 10 anos. Nao foram incluidos nesta serie pacientes nos quais a aneurismectomia foi procedimento cirurgico coadjuvante da revascularizacao miocardica, mas tao somente aqueles em que o aneurisma ventricular isoladamente se constituia em objeto da indicacao cirurgica. Na experiencia inicial ate 1978, o procedimento cirurgico realizado foi a aneurismectomia classica com sutura direta de seus bordos. A partir de agosto de 1978, para os aneurismas de colo largo passamos a utilizar a tecnica da reconstrucao geometrica proposta por Jatene, com utilizacao de retalho eliptico de dacron para a restauracao da parede ventricular.A finalidade do presente trabalho e apresentar uma protese semi-rigida de teflon que foi desenvolvida visando simplificar a utilizacao tatica deste principio e comparar os resultados obtidos entre os 21 pacientes operados com a tecnica da reconstrucao geometrica, cotejando-os com os 77 procedimentos da reconstrucao classica. Os autores apresentam ainda no trabalho os resultados imediatos e tardios das duas tecnicas assim como discutem os achados angiograficos da ventriculografia esquerda pos-operatoria realizada em 14 dos 77 pacientes em observacao