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1.
Int J Phytoremediation ; : 1-15, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38757757

ABSTRACT

In this study, artificial neural network (ANN) tools were employed to forecast the adsorption capacity of Malachite green (MG) by baru fruit endocarp waste (B@FE) under diverse conditions, including pH, adsorbent dosage, initial dye concentration, contact time, and temperature. Enhanced adsorption efficiency was notably observed under alkaline pH conditions (pH 10). Kinetic analysis indicated that the adsorption process closely followed a pseudo-second-order model, while equilibrium studies revealed the Langmuir isotherm as the most suitable model, estimating a maximum adsorption capacity of 57.85 mg g-1. Furthermore, the chemical adsorption of MG by B@FE was confirmed using the Dubinin-Radushkevich isotherm. Thermodynamic analysis suggested that the adsorption is spontaneous and endothermic. Various ANN architectures were explored, employing different activation functions such as identity, logistic, tanh, and exponential. Based on evaluation metrics like the coefficient of determination (R2) and root mean square error (RMSE), the optimal network configuration was identified as a 5-11-1 architecture, consisting of five input neurons, eleven hidden neurons, and one output neuron. Notably, the logistic activation function was applied in both the hidden and output layers for this configuration. This study highlights the efficacy of B@FE as an efficient adsorbent for MG removal from aqueous solutions and demonstrates the potential of ANN models in predicting adsorption behavior across varying environmental conditions, emphasizing their utility in this field.


The innovative aspect of this study lies in the utilization of a new and effective adsorbent for the removal of Malachite Green (MG), derived from the fruit endocarp of baru (Dipteryx alata Vog.). The baru fruit endocarp, typically discarded as solid waste during processing, was found to possess favorable characteristics for adsorption processes and provides an adsorption capacity that exceeds that of most other similar adsorbents. Additionally, integrating Artificial Neural Networks (ANNs) enables accurate modeling of the adsorption process, eliminating the need for extensive laboratory experiments. This contributes significantly to wastewater treatment research, enhancing effectiveness and sustainability in unwanted dye removal.

2.
Molecules ; 28(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37446808

ABSTRACT

The dynamical properties of four protic ionic liquids, based on the ethyltriazolium ([C2HTr124]) and the ethylimidazolium ([C2HIm]) cation, were investigated. The associated anions were the triflate ([TfO]) and the bistriflimide ([TFSI]). Ionic conductivity values and self-diffusion coefficients were measured and discussed, extending the discussion to the concept of fragility. Furthermore, in order to allow the measurement of the ionic conductivity of very small volumes (<0.5 mL) of ionic liquid under an inert and dry atmosphere, a new setup was developed. It was found that the cation nature strongly affected the transport properties, the [C2HTr124] cation resulting in slower dynamics than the [C2HIm] one. This was concluded from both conductivity and diffusivity measurements while for both properties, the anion had a lesser effect. By fitting the conductivity data with the Vogel-Fulcher-Tammann (VFT) equation, we could also estimate the fragility of these ionic liquids, which all fell in the range of very fragile glass-forming materials. Finally, the slower dynamics observed in the triazolium-based ionic liquids can be rationalized by the stronger interactions that this cation establishes with both anions, as deduced from the frequency analysis of relevant Raman signatures and density functional theory (DFT) calculations.


Subject(s)
Ionic Liquids , Anions , Cations , Electric Conductivity , Glass
3.
Chemistry ; 27(3): 1023-1030, 2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33022835

ABSTRACT

Spherical ruthenium nanoparticles (NPs) with a narrow size distribution were synthesised in ethanol by a facile low-temperature solvothermal process without the assistance of templates, structure-directing agents or post annealing/reduction treatments. Surface passivation with a fluorescent perylene dye (EP), and with silane ligands (ETMS), both initially bearing alkyne groups and subsequently forming vinylidene linkages, provided stable suspensions of the marginally soluble free EP. Quantitative analysis of the suspension gave an estimated EP surface coverage of 15 %, corresponding to an EP/ETMS mole ratio of ≈1:6. Photophysical evaluation of the bound and free dye revealed similar absorption bands and extinction coefficients and improved properties for the bound state, including enhanced fluorescence in the visible range for the bound dye, an extended absorption range into the near-UV providing strong emission in the visible, and significantly improved photostability. The physical basis of the enhanced photophysical properties, potential routes to further improvements and the implications for applications are discussed.

5.
Acta Parasitol ; 63(3): 645-646, 2018 Sep 25.
Article in English | MEDLINE | ID: mdl-29975643

ABSTRACT

Neospora caninum is a protozoan responsible for abortions, stillbirths (mainly among cattle) and neuromuscular diseases in dogs. Its importance in wild species and its impact on the environmental preservation of different ecosystems have been little described. This study aimed to investigate the presence of anti-N. caninum antibodies in feral cats on the island of Fernando de Noronha and contribute epidemiological data on this disease in these animals and its impact on the environmental preservation of the island. Serum samples from 257 feral cats on the island were analyzed through the Neospora agglutination test (NAT) to search for anti-Neospora caninum antibodies. Among the 257 serum samples analyzed, 8 (3.11%) were positive in the NAT. The antibody titers were 20 in seven animals (87.5%) and 40 in one animal (12.5%). These results demonstrate that feral cats are exposed to infection by N. caninum on the island of Fernando de Noronha, at a low frequency. Greater knowledge on this infection in this animal species in this insular environment is important for elucidating its impact on the conservation of species and the maintenance of this parasite on the island.


Subject(s)
Antibodies, Protozoan/blood , Cat Diseases/parasitology , Coccidiosis/veterinary , Neospora/immunology , Agglutination Tests/veterinary , Animals , Animals, Wild , Brazil/epidemiology , Cats , Coccidiosis/epidemiology , Coccidiosis/parasitology , Islands , Neospora/isolation & purification , Seroepidemiologic Studies
6.
Acta sci., Biol. sci ; 40: e39468, 20180000. ilus, tab, graf
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460829

ABSTRACT

Biodiesel is a clean renewable fuel used as alternative energy source to diesel and it is commercialized as a minor component in diesel blends. Similarly to diesel, biodiesel spill is a source of contamination for the ecosystem making necessary to provide effective remediation strategies. Bioremediation is a technology that has been applied with success to clean up hydrocarboncontaminated environments. In this study, fungal bioaugmentation strategy was compared with natural attenuation during bioremediation of a sandy soil contaminated with diesel, biodiesel and blends (B20 and B50). Respirometric assays simulating the contamination of soil were carried out in Bartha flasks used to measure microbial CO2 production. Penicillium sp. AV4 isolated from the wastewater of a biodiesel factory has the ability to degrade the fuels and was used in bioaugmentation. After 111 days, CO2 evolution demonstrated no significant difference in soil microbial activity between fungal augmentation and natural attenuation treatments for all fuels. The lack of influence of Penicillium sp. AV4 can be related to its inability to compete with soil microorganisms and/or increase its metabolic activity. During natural attenuation, B50 showed a higher CO2 production, followed by the B100, B20 and diesel, which is less biodegradable. Therefore, from a biodegradation perspective, biodiesel could be more beneficial than diesel during bioremediation spill.


Biodiesel é um combustível renovável utilizado como fonte energética alternativa ao diesel e é comercializado misturado a esse combustível. Assim como o diesel, derramamentos de biodiesel são fontes de contaminação dos ecossistemas, sendo necessário aplicar estratégias para a remediação. A biorremediação é uma tecnologia que vem sendo aplicada com sucesso para remediar ambientes contaminados com hidrocarbonetos. Neste trabalho, o bioenriquecimento fúngico foi comparado à atenuação natural durante a biorremediação de um solo arenoso contaminado com diesel, biodiesel e misturas (B20 e B50). Ensaios respirométricos foram efetuados, utilizando respirômetros de Bartha para avaliar a produção microbiana de CO2 no solo contaminado. Penicillium sp. AV4, isolado de efluentes de usina de biodiesel, possui a capacidade de degradar os combustíveis e foi usado no bioenriquecimento. Após 111 dias, a evolução de CO2 devido à atividade microbiana no solo não apresentou diferença estatística entre o bioenriquecimento fúngico e a atenuação natural, considerando todos os combustíveis. A ineficácia do fungo pode estar relacionada com sua incapacidade de competir com os microrganismos do solo e/ou expressar sua atividade metabólica degradadora. Durante a atenuação natural, B50 demonstrou maior produção de CO2, seguido por B100, B20 e diesel, o qual é menos biodegradável. Do ponto de vista da biodegradação, o biodiesel pode ser mais facilmente biorremediado do que o diesel.

7.
eNeuro ; 4(6)2017.
Article in English | MEDLINE | ID: mdl-29255796

ABSTRACT

Brain-derived neurotrophic factor (BDNF) is an important mediator of long-term synaptic potentiation (LTP) in the hippocampus. The local effects of BDNF depend on the activation of translation activity, which requires the delivery of transcripts to the synapse. In this work, we found that neuronal activity regulates the dendritic localization of the RNA-binding protein heterogeneous nuclear ribonucleoprotein K (hnRNP K) in cultured rat hippocampal neurons by stimulating BDNF-Trk signaling. Microarray experiments identified a large number of transcripts that are coimmunoprecipitated with hnRNP K, and about 60% of these transcripts are dissociated from the protein upon stimulation of rat hippocampal neurons with BDNF. In vivo studies also showed a role for TrkB signaling in the dissociation of transcripts from hnRNP K upon high-frequency stimulation (HFS) of medial perforant path-granule cell synapses of male rat dentate gyrus (DG). Furthermore, treatment of rat hippocampal synaptoneurosomes with BDNF decreased the coimmunoprecipitation of hnRNP K with mRNAs coding for glutamate receptor subunits, Ca2+- and calmodulin-dependent protein kinase IIß (CaMKIIß) and BDNF. Downregulation of hnRNP K impaired the BDNF-induced enhancement of NMDA receptor (NMDAR)-mediated mEPSC, and similar results were obtained upon inhibition of protein synthesis with cycloheximide. The results demonstrate that BDNF regulates specific populations of hnRNP-associated mRNAs in neuronal dendrites and suggests an important role of hnRNP K in BDNF-dependent forms of synaptic plasticity.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Dendrites/metabolism , Heterogeneous-Nuclear Ribonucleoprotein K/metabolism , Hippocampus/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Synapses/metabolism , Animals , Animals, Outbred Strains , Cells, Cultured , Excitatory Postsynaptic Potentials/physiology , Female , HEK293 Cells , Heterogeneous-Nuclear Ribonucleoprotein K/genetics , Hippocampus/cytology , Humans , Male , Microarray Analysis , Microelectrodes , RNA Transport/physiology , RNA, Messenger/metabolism , Rats, Sprague-Dawley , Rats, Wistar , Synaptosomes/metabolism
8.
Am J Dent ; 30(1): 3-8, 2017 02.
Article in English | MEDLINE | ID: mdl-29178707

ABSTRACT

PURPOSE: To investigate the fracture resistance of weakened roots restored with prefabricated or CAD/CAM-customized posts and cores as well as the thickness of the cement film and the presence of voids in the cement. METHODS: The roots of 40 human premolars were weakened by removing internal dentin with a diamond bur (2.5 mm in the coronal third and 1.5 mm in the apical third) and restored with prefabricated posts (PPs) or customized posts (CPs) with or without a zirconia crown (n= 10). Posts and crowns were cemented with resin cement. Microtomography was used to determine the thickness of the cement film and whether voids were present. After fatigue testing (1 million cycles, 50 N, 5 Hz, 36.5°C), the specimens underwent compression testing with an oblique load (30°, 1 mm/minute) and fracture strengths were recorded (N). Fracture strength and film thickness were analyzed with ANOVA and the Games-Howell test; the variable presence of voids was analyzed with the Mann-Whitney test (α= 5%). RESULTS: Mean fracture strengths varied between 640.4 and 792.9 N and did not differ significantly between groups. The CP group had a thinner cement film and fewer voids than the PP group. There was a positive, statistically significant correlation (Spearman, R=0.488, P= 0.029) between these variables. CLINICAL SIGNIFICANCE: CAD/CAM-manufactured glass-fiber posts and cores do not affect the fracture strength of flared root canals or cause catastrophic failure of the root when used with zirconia crowns.


Subject(s)
Computer-Aided Design , Post and Core Technique/instrumentation , Root Canal Therapy , Tooth Fractures/prevention & control , Crowns , Dental Cements/chemistry , Dental Materials/chemistry , Dental Stress Analysis , Glass/chemistry , Humans , In Vitro Techniques , Molar , Tooth Root , Zirconium/chemistry
9.
Braz. arch. biol. technol ; 60: e17160101, 2017. tab, graf
Article in English | LILACS | ID: biblio-839075

ABSTRACT

ABSTRACT This study investigated the biosorption of the anionic textile dyes: Reactive Red 239 (RR239), Reactive Black B (RBB) and Direct Blue 85 (DB85) according to pH, biomass dosage, contact time and dye concentration onto waste beer yeast slurry. The kinetics and isotherm of the removal of dyes were also studied. The equilibrium of biosorption reaction was reached after 30 min for the reactive dyes and after 60 min for the direct dye. Optimum decolorization was observed at pH 2 and 0.63 g/L of biomass dosage. The kinetic data of the three dyes were better described by the pseudo second-order model. The adsorption process followed the Langmuir isotherm model and the biosorption capacity being estimated to be 152.9, 162.7 and 139.2 mg/g for RR239, RBB and DB85, respectively. Our findings indicated that the waste beer yeast slurry was an attractive low-cost biosorbent for the removal of anionic textile dyes from aqueous solution.

10.
RSBO (Impr.) ; 12(2): 143-150, Apr.-Jun. 2015. ilus, tab
Article in English | LILACS | ID: lil-792036

ABSTRACT

Introduction: Most of techniques for determining the occlusal vertical dimension (OVD) of edentulous patients are based on soft tissues references, which lead to measurement discrepancies. Objective: To propose a method to obtain the OVD of edentulous patients during the confection of complete dentures considering the lower facial height established by Ricketts (LFHr) or the lower facial height obtained from cephalometric analysis of dentulous patients (LFHd). Material and methods: The OVD of 11 edentulous patients was determined by the association of 3 clinical methods. On each patient's bite plates a metallic ball was fixed and the patient was submitted to lateral radiographic to obtain the lower facial height (LFHe) from cephalometric analysis. Additionally, from 40 lateral cephalograms of dentulous patients the LFHd was obtained. After that, the distance between metallic balls (DMB, in mm) was calculated to verify the linear difference when LFHe was changed to LFHd or LFHr, which provided the amount of wax to be added or removed from the bite plates, establishing a new method of OVD determination. LFHe, LFHd and LFHr values were submitted to t e z statistical tests and DMB differences were analyzed by Student's t-test (α=0.05). Results: LFHr (47.0±4.0o a) was statistically higher than LFHd (44.9±5.6o b) and LFHe (43.5±3.5o b). There was statistical difference on linear discrepancies calculated between the LFHe and LFHd (1.7±4.1mm a) or LFHr (4.2±4.1mm b). Conclusion: The use of the cephalometric analysis showed to be a useful auxiliary tool in determining the intermaxillary relationship. However, this method must be associated with different clinical methods of OVD determination and it is recommended that regional references are used to calculate the linear discrepancies.

11.
RSBO (Impr.) ; 11(3): 313-318, Jul.-Sep. 2014. ilus
Article in English | LILACS | ID: lil-778297

ABSTRACT

The relationship between health systems and higher education is of fundamental importance to establish oral health improvements for population. Currently, primary attention's goal is to determine the quality of life of a given population through total denture rehabilitation. Thus the aim of this study was to report the integrated actions between the Health Secretary of the city of Curitiba and the University during the training in Total Denture of primary attention professionals. Fifty dental professional from nine sanitary districts of the city of Curitiba were enrolled in the training. The project comprised theoretical and practical classes during a period of five weeks, from June to July of 2013. More similar actions reinforce the university's role in improving the quality of life of the population and the university integration with public service aiming at updating dental professionals.

12.
J Contemp Dent Pract ; 15(1): 26-8, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24939260

ABSTRACT

OBJECTIVE: The aim of this study to investigate the effects of different polymerization protocols on the cuspal movement in class II composite restorations. MATERIALS AND METHODS: Human premolar teeth were prepared with class II cavities and then restored with composite and three-step and two-step etch-and-rinse adhesive systems under different curing techniques (n = 10). It was used a light- emitting-diode curing unit and the mode of polymerization were: standard (exposure for 40 seconds at 700 mW/cm(2)), pulse-delay (initial exposure for 6 seconds at 350 mW/cm(2) followed by a resting period of 3 minutes and a final exposure of 37 seconds at 700 mW/cm(2)) and soft-start curing (exposure 10 seconds at 350 mW/cm(2) and 35 seconds at 700 mW/cm(2)). The cuspal distance (µm) was measured before and after the restorative procedure and the difference was recorded as cuspal movement. The data were submitted to two-way ANOVA and Bonferroni test (p < 0.05). RESULTS: The type of adhesive system did not influenced the cuspal movement for all the curing methods. Standard protocol showed the highest values of cuspal movement and was statistically different from the pulse-delay and soft-start curing modes. CONCLUSION: Although the cuspal displacement was not completely avoided, alternative methods of photocuring should be considered to minimize the clinical consequences of composites contraction stress.


Subject(s)
Bicuspid/anatomy & histology , Composite Resins/chemistry , Dental Materials/chemistry , Dental Restoration, Permanent/classification , Light-Curing of Dental Adhesives/methods , Tooth Crown/anatomy & histology , Acid Etching, Dental/methods , Biomechanical Phenomena , Bisphenol A-Glycidyl Methacrylate/chemistry , Curing Lights, Dental/classification , Dental Cavity Preparation/classification , Humans , Light-Curing of Dental Adhesives/instrumentation , Materials Testing , Polymerization , Radiation Dosage , Resin Cements/chemistry , Stress, Mechanical , Surface Properties , Time Factors
13.
RSBO (Impr.) ; 10(2): 128-134, Apr.-Jun. 2013. ilus, tab
Article in English | LILACS | ID: lil-695925

ABSTRACT

Introduction: The success of implant-supported prostheses is related to the passive union between the prostheses’ connections and the implants, so it is necessary to obtain an accurate working cast. Objective: To evaluate the accuracy of the transfer impressions of implants performed with individual acrylic resin trays and conventional trays using polyvinyl siloxane. Material and methods: To carry out the transfer impressions, a master cast with four external hexagon implants parallel to each other was used. Five impressions were made with individual acrylic resin trays and five other impressions with modified conventional trays, opened in the region of the implants. The linear measurements between the implants were made with a digital caliper with an accuracy of 0.01 mm and the results were statistically evaluated (alpha = %). Results: For the points AB and BC, the measurements obtained with the individual trays were statistically similar to the master cast. For the points CD and DA no statistical differences among the three groups were observed. Conclusion: Given the obtained results and the methodology used, it can be concluded that the impressions performed with individual trays presented higher accuracy compared to the ones obtained with conventional trays.

14.
J Prosthodont ; 22(5): 413-8, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23387526

ABSTRACT

Root canal perforation and root resorption are challenging clinical conditions to correctly diagnose and treat, especially when they occur in anterior teeth. This clinical report describes the computed tomography findings, endodontic treatment, prosthetic rehabilitation, and clinical outcome of an iatrogenic root perforation and internal resorption in a maxillary central incisor. The case management consisted of endodontic retreatment, periodontal surgery, and prosthetic rehabilitation. Gray mineral trioxide aggregate (MTA) was used to fill the resorption space and seal the perforation. The prosthetic treatment was performed with glass fiber-reinforced dowels and all-ceramic crowns. No signs or symptoms, including discomfort, pain, or esthetic defects were observed in 30 months of follow-up.


Subject(s)
Aluminum Compounds/therapeutic use , Calcium Compounds/therapeutic use , Incisor/injuries , Oxides/therapeutic use , Root Canal Filling Materials/therapeutic use , Root Resorption/therapy , Silicates/therapeutic use , Tooth Root/injuries , Tooth, Nonvital/rehabilitation , Adult , Ceramics/chemistry , Cone-Beam Computed Tomography/methods , Crown Lengthening/methods , Crowns , Dental Materials/chemistry , Drug Combinations , Female , Follow-Up Studies , Glass/chemistry , Humans , Iatrogenic Disease , Periapical Diseases/therapy , Post and Core Technique/instrumentation , Retreatment , Root Canal Therapy/methods , Surgical Flaps/surgery , Treatment Outcome
15.
Am J Dent ; 25(1): 35-8, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22558690

ABSTRACT

PURPOSE: To evaluate the root fracture strength of human single-rooted premolars restored with customized fiberglass post-core systems after fatigue simulation. METHODS: 40 human premolars had their crowns cut and the root length was standardized to 13 mm. The teeth were endodontically treated and embedded in acrylic resin. The specimens were distributed into four groups (n=10) according to the restorative material used: prefabricated fiber post (PFP), PFP+accessory fiber posts (PFPa), PFP+unidirectional fiberglass (PFPf), and unidirectional fiberglass customized post (CP). All posts were luted using resin cement and the cores were built up with a resin composite. The samples were stored for 24 hours at 37 degrees C and 100% relative humidity and then submitted to mechanical cycling. The specimens were then compressive-loaded in a universal testing machine at a crosshead speed of 0.5 mm/minute until fracture. The failure patterns were analyzed and classified. Data was submitted to one-way ANOVA and Tukey's test (alpha = 0.05). RESULTS: The mean values of maximum load (N) were: PFP - 811.4 +/- 124.3; PFPa - 729.2 +/- 157.2; PFPf- 747.5 +/- 204.7; CP - 762.4 +/- 110. Statistical differences were not observed among the groups. All groups showed favorable restorable failures. Fiberglass customized post did not show improved fracture resistance or differences in failure patterns when compared to prefabricated glass fiber posts.


Subject(s)
Dental Materials/chemistry , Glass/chemistry , Post and Core Technique/instrumentation , Bicuspid/injuries , Cementation/methods , Composite Resins/chemistry , Dental Prosthesis Design , Dental Restoration Failure , Dental Stress Analysis/instrumentation , Humans , Humidity , Materials Testing , Resin Cements/chemistry , Stress, Mechanical , Surface Properties , Temperature , Time Factors , Tooth Fractures/physiopathology , Tooth Root/injuries , Tooth, Nonvital/physiopathology
16.
J Parasitol ; 98(3): 690-1, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22263703

ABSTRACT

The object of this study was to investigate Toxoplasma gondii antibodies and parasite DNA in pigs in the state of Pernambuco, Brazil. Blood samples were collected from 305 slaughtered pigs in 11 municipalities, and their sera were tested for T. gondii antibodies using the indirect fluorescent antibody test (IFAT, cutoff 1:64); 38 (12.5%) samples were positive. Attempts were made to detect T. gondii DNA in the heart tissue of seropositive pigs using the B 1 gene and PCR; 21 (55.2%) of the 38 hearts were positive. This is the first detection of T. gondii DNA in tissues of serologically positive swine in the State of Pernambuco, Brazil.


Subject(s)
Swine Diseases/epidemiology , Toxoplasmosis, Animal/epidemiology , Abattoirs , Animals , Antibodies, Protozoan/blood , Brazil/epidemiology , DNA, Protozoan/chemistry , DNA, Protozoan/isolation & purification , Fluorescent Antibody Technique, Indirect/veterinary , Heart/parasitology , Polymerase Chain Reaction/veterinary , Prevalence , Sequence Analysis, DNA/veterinary , Swine , Swine Diseases/parasitology , Toxoplasma/genetics , Toxoplasma/immunology , Toxoplasma/isolation & purification
17.
Eur J Dent ; 5(1): 107-12, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21228960

ABSTRACT

Customized glass fiber posts that is well adjusted into the root canal and have mechanical properties similar to those of dentin may be a suitable treatment for severely compromised endodontically treated teeth. This article reports a 3-year follow up of severely damaged endodontically treated teeth restored with unidirectional fiber glass customized post and core system instead of a conventional fiber post. The fabrication of this glass fiber customized post is a simple technique, providing an increased volume of fibers into the root canal, and an adequate polymerization of the post-core system. Over a three-year period, the treatments demonstrated good clinical and radiographic characteristics, with no fracture or loss of the post and/or crown. This technique can be considered effective, less invasive, and suitable for restore endodontically treated teeth.

18.
Pediatr Dent ; 32(5): 428-32, 2010.
Article in English | MEDLINE | ID: mdl-21070711

ABSTRACT

Crown-root fractures are complex traumatic injuries that require multidisciplinary management and afford uncertain prognosis. The purpose of this clinical article was to report the case of crown-root fracture where a multidisciplinary approach was successfully executed. A 10-year-old male patient who suffered a complicated crown-root fracture on a permanent maxillary central incisor was treated using an intentional 180°-rotation replantation technique, followed by endodontic therapy and restoration with resin composite. Two years after the initial treatment, the case was stable and the tooth was restored with a resin core and a ceramic crown. This article describes how adequate multidisciplinary treatment planning, coordination, and execution are necessary for similar cases to be properly managed. It can be concluded that the intentional replantation with 180°-rotation allowed a more conservative approach, showing, in this case, a clinical success without resorption.


Subject(s)
Incisor/injuries , Tooth Fractures/therapy , Tooth Replantation , Child , Crowns , Humans , Male , Maxilla , Patient Care Team , Post and Core Technique , Root Canal Therapy , Tooth Crown/injuries , Tooth Root/injuries
19.
Acta odontol. venez ; 48(1): 164-169, mar. 2010. tab
Article in Spanish | LILACS | ID: lil-630263

ABSTRACT

Debido a la excelente estética y biocompatibilidad, las restauraciones con cerámicas son frecuentemente utilizadas en la práctica clínica diaria. A pesar de la evolución de las propiedades mecánicas de las cerámicas, existen casos extensos en que la indicación principal es el uso de coronas metalo-cerâmicas. Frente a la posibilidad de la fractura de esas prótesis, que ocurren del 5 y al 10% en 10 años de uso, existe la opción de reparar dichas prótesis, disminuyendo el costo y el tiempo operacional. Cuando la falla expone la porción metálica de la pieza, se indica una reparación indirecta, que consiste en la confección de una sobre estructura, cementada en la región previamente preparada, a partir de un modelo de trabajo. El objetivo de este trabajo fue demostrar una técnica de reparación indirecta de prótesis parciales fijas utilizando una sobre estructura metalo-cerámica.


Due the excellent esthetic and biocompatibility, metal ceramic restrations are frequently used at clinical daily practice. In sipte of the ceramic mechanical properties evolution, there are extensive cases that the primary indication are metalceramic crowns. Ahead of the possible fractures of these prosthesis, that happen from the 5 to 10% in 10 years of use, there are option to repair it, diminishing cost and chair time. When the failure expose the metal portion it indicates a indirect repair wich consist in manufacturing of a overlay, cemented on region that was previosly prepared, from a work cast. The aim of this study was demonstrate a indirect repair technique of fixed partial dentures using a metalceramic overlay.

20.
Braz. arch. biol. technol ; 52(6): 1571-1578, Nov.-Dec. 2009. tab, ilus, graf
Article in English | LILACS | ID: lil-539123

ABSTRACT

In this study, the potential for using an inoculum composed of a mixed-culture of bacteria and fungi, isolated from a landfarming at the Paulínia Oil Refinery, Brazil, to degrade oil residues generated in the process of petroleum refinement was investigated. The isolation of these microorganisms was carried out beforehand, assuming that they would be better adapted to petroleum hydrocarbons, as the landfarming consisted of an area impacted by the deposit of such compounds. The Bartha and Pramer respirometric test was used to measure the rate of biodegradation of the hydrocarbons by the mixed-culture of microorganisms via the evolution of CO2. The results obtained with respect to the efficiency of biodegradation showed no significant differences (P>0.05), indicating no increase in the biodegradation process using the inoculum. The addition of nutrients (N, P, K) also did not contribute to an increase in biodegradation of the oil residue studied.


Neste estudo foi investigado o potencial de um inóculo composto de cultura mista de bactérias e fungos, isolados do landfarming da Refinaria de Paulínia, Brasil, em degradar resíduos oleosos gerados no processo de refinamento de petróleo. O isolamento desses microrganismos foi realizado previamente, supondo-se que estejam melhor adaptados aos hidrocarbonetos de petróleo uma vez que o landfarming consiste em área impactada por deposição de tais compostos. Utilizou-se o teste respirométrico de Bartha e Pramer no intuito de verificar a taxa de biodegradação dos hidrocarbonetos pela cultura mista de microrganismos através da evolução de CO2. Os resultados obtidos para a eficiência da biodegradação não apresentaram diferença estatisticamente significativa (P>0.05) indicando que não houve aumento do processo de biodegradação com o uso do inóculo. A adição de nutrientes (N, P, K) tampouco contribuiu para aumentar a biodegradação do resíduo oleoso estudado.

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