The influence of mandibular ridge anatomy on treatment outcome with conventional complete denture.

Visto que indicadores de prognóstico são uma ferramenta importante para a seleção de pacientes a serem tratados com prótese total, este estudo investigou a influência da forma e da resiliência do rebordo alveolar mandibular sobre a retenção e estabilidade de próteses totais convencionais. Noventa e três pacientes desdentados portadores de próteses totais superior e inferior compuseram a amostra. Os dados foram coletados quanto a forma e resiliência do rebordo mandibular. As próteses foram avaliadas para a retenção e estabilidade utilizando-se uma ferramenta objetiva e reproduzível. As associações entre as características clínicas do rebordo alveolar mandibular e retenção e estabilidade das próteses foram analisados por meio dos testes qui-quadrado e exato de Fisher (α = 0.05). Observou-se associação significativa entre a forma do rebordo e a estabilidade da prótese (p <0,05), enquanto que a resiliência foi associada significativamente com a retenção (p <0,001). Baseando-se nos resultados, a resiliência e forma do rebordo mandibular influenciaram, respectivamente, a retenção e estabilidade de próteses totais convencionais.

Origem física das curvas sigmoidais respiratórias pressão-volume: recrutamento alveolar e elasticidade não-linear

An important unsolved problem in medical science concerns the physical origin of the sigmoidal shape of pressure volume curves of healthy (and some unhealthy) lungs. Such difficulties are expected because the lung, which is the most important structure in the respiratory system, is extremely complex. Its rheological properties are unknown and seem to depend on phenomena occurring from the alveolar scale up to the thoracic scale. Conventional wisdom holds that linear response, i.e., Hooke s law, together with alveolar overdistention, play a dominant role in respiration, but such assumptions cannot explainthe crucial empirical sigmoidal shape of the curves. In this doctorate thesis, we propose an alternative theory to solve this problem, based on the alveolar recruitment together with the nonlinear elasticity of the alveoli. This theory suggests that recruitment may be the predominant factor shaping these curves in the entire range of pressures normally employed in experiments. The proposed model correctly predicts the observed sigmoidal pressure volume curves, allowing us to discuss adequately the importance of this result, as well as its implications for medical practice

Falhas e complicações com o uso de prótese parcial removível inferior de extremidade livre bilateral

Aim: To determine the frequency and type of complications related to removable partial denture (RPD) less, Kennedy Class I, over time . Materials and Methods: This observational study consisted of a sample of 65 users PPR lower arches in Kennedy Class I and dentures, rehabilitated in the Department of Dentistry, Federal University of Rio Grande do Norte (UFRN). Patients were followed through periodic controls during periods of 60 days, 6 months and 1 year from installation. After the first year of control had other returns annually. The occurrence of complications or prosthetic failure was observed and recorded in a specific clinical record over 39 months. The patterns of failures observed were classified in the following situations: occurrence of traumatic ulcers after 2 months of installation, lack of retention, fracture or caries in the rest, fracture or dislocation of the artificial teeth, the larger connector fracture, fracture clip fracture support, poor support (need to reline the denture) and prosthesis fracture. Results: The incidence of complications was low frequency, being higher in the second year of use of the prosthesis. Among the complications that occurred more is the loss of retention (31.57%). Failures more severe and difficult to solve as the fracture elements of the metal structure of the PPR had low occurrence and were represented by only one case of the larger connector (5.3%) fractures. Conclusion: Removable partial dentures mandibular free end opposing of the conventional dentures have a low complication rate after 39 months of use when subjected to periodic controls

Análise estratigráfica de subsuperfície do Devoniano Inferior da Bacia do Rio do Peixe, Nordeste do Brasil

Subsurface stratigraphic analysis of Devonian strata from the Rio do Peixe Basin, newly recognized by palynological studies, has resulted in the identification of two new lithostratigraphic units assembled in the Santa Helena Group. The Pilões Formation, the lower unit, is composed mainly of dark mudstones and medium-tovery fine-grained sandstones, with minor conglomerates and breccias. The Triunfo Formation, the upper unit, comprises whitish grey, kaolinitic, coarse-grained to conglomeratic, cross stratified sandstones and conglomerates, with interbedded mudstones and fine-grained sandstones. These units were characterized using cores, sidewall and cuttings samples, conventional logs and image log, from three wells drilled by PETROBRAS, and 3D seismic data. The Pilões Formation is interpreted as prodeltaic facies, with lesser associated subaqueous talus, debrite and sandy turbidite lobe facies, distal part of fandelta and braided fluviodeltaic facies of Triunfo Formation. The Santa Helena Group corresponds to the Lower Devonian tectono-sequence deposited in a NW-SE-trending graben during a transgressiveregressive cycle. With 343 meters of thickness (isochore) in well 1-PIL-1-PB (Pilões 1), this sequence has a non-conformity at the lower boundary and its upper boundary is an unconformity with the Lower Cretaceous tectono-sequence (Rio do Peixe Group), that represents a hiatus of about 265 million years. Ignimbrites and coignimbrite breccias (Poço da Jurema volcanic breccia), related to an unknown pyroclastic volcanic event, were recognized at the northern margin of the Sousa halfgraben. Evidence from well data suggests that this event is coeval with the Devonian graben filling. The present study indicates a polyhistorical tectono-volcanosedimentary evolution of the basin. This lithostratigraphic update brings new perspectives for geological research in the Rio do Peixe Basin, as well as in other inland basins of the Northeastern of Brazil. The results of the research also contribute to the kwnoledge of the Borborema Province and western Gondwana paleogeography during the Early Devonian.

Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos

GURGEL, Bruno Cesar de vasconcelos.Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos. 2003.97f. Dissertaçao (Mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba. Piracicaba, 2003. Disponivel em: . Acesso em: 04 out. 2010.

Estudo de estratégias de otimização para poços de petróleo com elevação por bombeio de cavidades progressivas

The progressing cavity pump artificial lift system, PCP, is a main lift system used in oil production industry. As this artificial lift application grows the knowledge of it s dynamics behavior, the application of automatic control and the developing of equipment selection design specialist systems are more useful. This work presents tools for dynamic analysis, control technics and a specialist system for selecting lift equipments for this artificial lift technology. The PCP artificial lift system consists of a progressing cavity pump installed downhole in the production tubing edge. The pump consists of two parts, a stator and a rotor, and is set in motion by the rotation of the rotor transmitted through a rod string installed in the tubing. The surface equipment generates and transmits the rotation to the rod string. First, is presented the developing of a complete mathematical dynamic model of PCP system. This model is simplified for use in several conditions, including steady state for sizing PCP equipments, like pump, rod string and drive head. This model is used to implement a computer simulator able to help in system analysis and to operates as a well with a controller and allows testing and developing of control algorithms. The next developing applies control technics to PCP system to optimize pumping velocity to achieve productivity and durability of downhole components. The mathematical model is linearized to apply conventional control technics including observability and controllability of the system and develop design rules for PI controller. Stability conditions are stated for operation point of the system. A fuzzy rule-based control system are developed from a PI controller using a inference machine based on Mandami operators. The fuzzy logic is applied to develop a specialist system that selects PCP equipments too. The developed technics to simulate and the linearized model was used in an actual well where a control system is installed. This control system consists of a pump intake pressure sensor, an industrial controller and a variable speed drive. The PI control was applied and fuzzy controller was applied to optimize simulated and actual well operation and the results was compared. The simulated and actual open loop response was compared to validate simulation. A case study was accomplished to validate equipment selection specialist system

Obtenção de compósitos cerâmicos baseados em Al2O3/TiC através dos precursores poliméricos

The obtaining of ceramic materials from polymeric precursors is subject of numerous studies due to lower energy costs compared to conventional processing. The aim of this study is to investigate and improve the mechanism for obtaining ceramic matrix composite (CMC) based on SiOC/Al2O3/TiC by pyrolysis of polysiloxane in the presence of an active filler and inert filler in the pyrolysis temperature lower than the usually adopted for this technique, with greater strength. It also investigates the influence of pyrolysis temperature, the content of Alas active filler, the presence of infiltrating agents (Al, glass and polymer) after pyrolysis, temperature and infiltration time on some physical and mechanical properties. Alumina is used as inert filler and Al and Ti as active filler in the pyrolysis. Aluminum, glass and polysiloxane are used as agents infiltrating the post-pyrolysis. The results are analyzed with respect to porosity and bulk density by the Archimedes method, the presence of crystalline phases by X-ray diffraction (XRD) and microstructure by scanning electron microscopy (SEM). The ceramic pyrolyzed between 850 °C 1400 °C contain porosity 15% to 33%, density 2.34 g/cm3 and flexural strength at 4 points from 30 to 42 MPa. The microstructure features are porous, with an array of Al2O3 reinforced by TiC particles and AlTi3. The infiltration post-pyrolysis reveals decrease in porosity and increase density and strength. The composites have potential applications where thermal stability is the main requirement

Obtenção de pós de Nb a partir da redução aluminotérmica com ignição por plasma

The aluminothermic reduction consists in an exothermic reaction between a metallic oxide and aluminum to produce the metal and the scum. The extracted melted metal of that reaction usually comes mixed with particles of Al2O3 resulting of the reduction, needing of subsequent refine to eliminate the residual impure as well as to eliminate porosities. Seeking to obtain a product in powder form with nanometric size or even submicrometric, the conventional heat source of the reaction aluminothermic , where a resistor is used (ignitor) as ignition source was substituted, for the plasma, that acts more efficient way in each particle of the sample. In that work it was used as metallic oxide the niobium pentoxide (Nb2O5) for the exothermal reaction Nb2O5 + Al. Amounts stoichiometric, substoichiometric and superestoichiometric of aluminum were used. The Nb2O5 powder was mixed with aluminum powder and milled in planetarium of high energy for a period of 6 hours. Those powders were immerged in plasm that acts in a punctual way in each particle, transfering heat, so that the reaction can be initiate and spread integrally for the whole volume of the particle. The mixture of Nb2O5 + Al was characterized through the particle size analysis by laser and X-ray diffraction (DRX) and the obtained product of reaction was characterized using the electronic microscopy of sweeping (MEV) and the formed phases were analyzed by DRX. Niobium powders with inferior sizes to 1 mm were obtained by that method. It is noticed, through the analysis of the obtained results, that is possible to accomplish the aluminothermic reduction process by plasma ignition with final particles with inferior sizes to the original oxide

Síntese e caracterização do carbeto de molibdênio nanoestruturado para fins catalíticos na reação de oxidação parcial do metano

The nanostructures materials are characterized to have particle size smaller than 100 nm and could reach 1 nm. Due to the extremely reduced dimensions of the grains, the properties of these materials are significantly modified relatively when compared with the conventional materials. In the present work was accomplished a study and characterization of the molybdenum carbide, seeking obtain it with particles size in the nanometers order and evaluate its potential as catalyst in the reaction of partial methane oxidation. The method used for obtaining the molybdenum carbide was starting from the precursor ammonium heptamolybdate of that was developed in split into two oven, in reactor of fixed bed, with at a heating rate of 5ºC/min, in a flow of methane and hydrogen whose flow was of 15L/h with 5% of methane for all of the samples. The studied temperatures were 350, 500, 600, 650, 660, 675 and 700ºC and were conducted for 0, 60, 120 and 180 minutes, and the percent amount and the crystallite size of the intermediate phases were determined by the Rietveld refinement method. The carbide obtained at 660ºC for 3 hours of reaction showed the best results, 24 nm. Certain the best synthesis condition, a passivating study was accomplished, in these conditions, to verify the stability of the carbide when exposed to the air. The molybdenum carbide was characterized by SEM, TEM, elemental analysis, ICP-AES, TG in atmosphere of hydrogen and TPR. Through the elemental analysis and ICP-AES the presence carbon load was verified. TG in atmosphere of hydrogen proved that is necessary the passivating of the molybdenum carbide, because occur oxidation in room temperature. The catalytic test was accomplished in the plant of Fischer-Tropsch of CTGAS, that is composed of a reactor of fixed bed. Already the catalytic test showed that the carbide presents activity for partial oxidation, but the operational conditions should be adjusted to improve the conversion

Desenvolvimento de um secador spray para obtenção de pós finos de precursores de nióbio

This work presents a spray-dryer designed to oxalate-niobate precursors and suitable for the production of Niobium Carbide. The dryer was intended to produce powders of controlled particle size. First, the precursor is dissolved in water to produce a solution of known concentration and then it is atomized on the spray-dryer to produce the powder. This equipment consists of a 304 stainless steel chamber, 0.48 m x 1.9 m (diameter x length), with a conical shape at the lower portion, which is assembled on a vertical platform. The chamber is heated by three 4 kW electrical resistances. In this process, drying air is heated as it flows inside a serpentine surrounding the chamber, in contrary to more traditional processes in which the hot drying air is used to heat the component. The air enters the chamber at the same temperature of the chamber, thus avoiding adherence of particles on the internal surface. The low speed flow is concurrent, directed from the top to the bottom portion of the chamber. Powders are deposited on a 0.4 m diameter tray, which separates the cylindrical portion from the conical portion of the chamber. The humid air is discharged though a plug placed underneath the collecting tray. A factorial experimental planning was prepared to study the influence of five parameters (concentration, input flow, operation temperature, drying air flow and spray air flow) on the characteristics of the powders produced. Particle size distribution and shape were measured by laser granulometry and scanning electronic microscopy. Then, the powders are submitted to reaction in a CH4 / H2 atmosphere to compare the characteristics of spray-dried powders with powders synthetizided by conventional methods

Novas alternativas de remoção de enxofre do óleo diesel utilizando tensoativos e microemulsões

The diesel combustion form sulfur oxides that can be discharged into the atmosphere as particulates and primary pollutants, SO2and SO3, causing great damage to the environment and to human health. These products can be transformed into acids in the combustion chamber, causing damage to the engines. The worldwide concern with a clean and healthy environment has led to more restrictive laws and regulations regulating the emission levels of pollutants in the air, establishing sulfur levels increasingly low on fuels. The conventional methods for sulfur removal from diesel are expensive and do not produce a zero-level sulfur fuel. This work aims to develop new methods of removing sulfur from commercial diesel using surfactants and microemulsion systems. Its main purpose is to create new technologies and add economic viability to the process. First, a preliminary study using as extracting agent a Winsor I microemulsion system with dodecyl ammonium chloride (DDACl) and nonyl phenol ethoxylated (RNX95) as surfactant was performed to choose the surfactant. The RNX95 was chosen to be used as surfactant in microemulsioned systems for adsorbent surface modification and as an extracting agent in liquid-liquid extraction. Vermiculite was evaluated as adsorbent. The microemulsion systems applied for vermiculite surface modification were composed by RNX95 (surfactant), n-butanol (cosurfactant), n-hexane (oil phase), and different aqueous phases, including: distilled water (aqueous phase),20ppm CaCl2solution, and 1500ppm CaCl2solution. Batch and column adsorption tests were carried out to estimate the ability of vermiculite to adsorb sulfur from diesel. It was used in the experiments a commercial diesel fuel with 1,233ppm initial sulfur concentration. The batch experiments were performed according to a factorial design (23). Two experimental sets were accomplished: the first one applying 1:2 vermiculite to diesel ratio and the second one using 1:5 vermiculite to diesel ratio. It was evaluated the effects of temperature (25°C and 60°C), concentration of CaCl2in the aqueous phase (20ppm and 1500ppm), and vermiculite granule size (65 and 100 mesh). The experimental response was the ability of vermiculite to adsorb sulfur. The best results for both 1:5 and 1:2 ratios were obtained using 60°C, 1500ppm CaCl2solution, and 65 mesh. The best adsorption capacities for 1:5 ratio and for 1:2 ratio were 4.24 mg sulfur/g adsorbent and 2.87 mg sulfur/g adsorbent, respectively. It was verified that the most significant factor was the concentration of the CaCl2 solution. Liquid-liquid extraction experiments were performed in two and six steps using the same surfactant to diesel ratio. It was obtained 46.8% sulfur removal in two-step experiment and 73.15% in six-step one. An alternative study, for comparison purposes, was made using bentonite and diatomite asadsorbents. The batch experiments were done using microemulsion systems with the same aqueous phases evaluated in vermiculite study and also 20ppm and 1500 ppm BaCl2 solutions. For bentonite, the best adsorption capacity was 7.53mg sulfur/g adsorbent with distilled water as aqueous phase of the microemulsion system and for diatomite the best result was 17.04 mg sulfur/g adsorbent using a 20ppm CaCl2solution. The accomplishment of this study allowed us to conclude that, among the alternatives tested, the adsorption process using adsorbents modified by microemulsion systems was considered the best process for sulfur removal from diesel fuel. The optimization and scale upof the process constitutes a viable alternative to achieve the needs of the market

Influência do kinesio taping® no desempenho neuromuscular do quadríceps femoral e na função do membro inferior em sujeitos saudáveis: ensaio clínico, controlado, randomizado, cego

Objective:To analyze the immediate effects of the Kinesio Taping® application on the quadriceps neuromuscular performance, postural balance and lower limb function in healthy subjects. Materials andmethods:This is a randomized, controlled, blinded clinical trial. Sixtyfemale volunteers(age: 23.3±2.5 years old, BMI: 22.2±2.1kg/m2)wererandomly assigned intothreegroups with20memberseach,and performedone of these threeprotocols: control -10 minutesof rest,experimental 1- patch application ontherectusfemoris (RF), vastuslateralis(VL) and vastusmedialis(VM) and experimental 2-KT application on the same muscles. Allunderwent an evaluationfor singleand triple hop distance, postural balance (baropodometry), joint position sense(JPS), peak torque (concentric and eccentricevaluation at 60°/s)and electromyographic activityof VL,before andafter intervention.Results: There wasasignificant increasein the jump distanceof thethreestudied groups,with no differencebetween groups.There were nosignificant changesin postural balance,JPS, concentricpeak torqueand RMSof the VLin none of the groups. There was a reduction ineccentricpeak torquein all groups, without differencesbetween groups.Conclusion:The KT application on the RF, VL and VMmusclesis not able tosignificantly improvelower limbfunction and postural balance, as well as the kneeextensor peaktorque, JPSand the VL muscleactivation amplitudeof healthy women.

Efeitos agudos do alongamento estático antes e após exercício e as características neuromusculares do membro inferior: estudo controlado, randomizado e cego

Objective: To evaluate the acute effects of static stretching before and after isokinetic exercise, neuromuscular and biomechanical properties of muscles Biceps Femoris (BF) and semitendinosus (ST). Methods: Eighty-nine volunteers of both genders, healthy and physically active, with a mean age of 22.52 ± 2.6 years and mean BMI 23.86 ± 3.2 kg/m² were randomized into 4 groups: Control Group (CG) made only one Protocol Exercise (PE) without performing the stretching, the Experimental Group 1 (EG1) did stretching before PE; EG2 did the stretching after PE and EG3 did stretching before and after PE. The volunteers were evaluated on the following variables: Range of motion (ROM), soreness, dynamometric variables concentric and eccentric, Neuromuscular Latency Time (NLT) and electromyographic. In the data analysis was assigned a significance level of 5%. Results: ADM and TLNM reported significant reduction in CG, but remained unchanged in GE with p<0,05 and p<0,01, respectively. As for the soreness, no differences between the groups. The electromyographic activity of the BF and ST, in the concentric phase, showed a significant decrease in all groups (p<0,01). However, in the eccentric phase, ST revealed reduction in all groups (p <0.01), except for the CG, while the BF remained unchanged in all groups. The PT showed significant reduction in both conditions (concentric and eccentric) for all groups, with no difference between them (p<0,01). Conclusion: The results of this study do not favor the use of static stretching, even of short duration, before physical activity. However, after exercise or at times unrelated to the sport, he should be given with the aim of avoiding muscle shortening

Satisfação dos usuários e qualidade dos tratamentos protéticos realizados nos centros de especialidades odontológicas da grande Natal RN

Aim: To evaluate user satisfaction and quality of prosthetic treatments performed in specialized dental clinics (CEOs) of Natal Metropolitan Region - RN. Methods: Cross-sectional study with subjects who underwent prosthetic CEOs in the cities of Natal, Macaíba, Parnamirim and Sao Goncalo do Amarante in the period 2007 to 2009. Data collection was performed by questionnaire, clinical examination of the oral cavity and examination of fabricated denture. This analysis involved the following aspects: retention, stability, aesthetics and prosthesis fixation. The variables are presented by means of absolute numbers and proportions. The determination of the association between the independent and dependent variables was conducted by the association of Chi-square test and Fisher exact test. Results: A total of 149 users, totaling 233 conventional dentures (148 upper and 85 lower). Most patients (56.4%) were rehabilitated with conventional complete dentures. The technical quality of the denture was regarded as satisfactory in the majority (52.7%), whereas the inferior dentures were rated as unsatisfactory in 90.5% of cases. Satisfaction with the prosthesis was 69.1% (N = 103). The average time to begin treatment was 3 months to receive while the prosthesis was 4 months old. The presence of injury from the upper prosthesis occurred in 21.5% of cases (N = 32), candidiasis being the most frequent (N = 18). The technical quality of the upper prosthesis (p=0,041), as well as retention (p=0,002) and stability (p<0,001) were significantly associated with user satisfaction. Conclusions: The specialized Dental clinics has been fulfilling its role of providing treatment of intermediate complexity for low-income population with the majority of satisfield patients, even when their dentures have problems of technical quality

Qualidade de vida, eficiência mastigatória e presença de disfunção temporomandibular em usuários de prótese parcial removível com arco dental curto inferior

Even nowadays there is in Brasil a large number of edentulous and a precarious financial condition of most of the population. In addition, World Health Organization aims for oral health, which consists on the maintenance of a natural dentition, functional and aesthetic composed of at least 20 teeth, without need of prosthetic intervention throughout life. From this and considering the lack of researches about the permanence of edentulous spaces in the oral cavity, and also avoiding overtreatment, this research has been proposed. Thus, the aim was to evaluate the effect of different lengths of the shortened lower dental arch in the presence or absence of a removable partial denture (RPD) on masticatory function, quality of life and occurrence of temporomandibular dysfunction. To achieve this goal, we compared the masticatory efficiency (colorimetric test), the oral comfort through the analysis of the impact of oral health in quality of life (OHIP-14), the presence of temporomandibular dysfunction (RDC/TMD) and the general quality of life (WHOQOL) of patients with shortened dental arches (SDA) (n=60), which is an arch with a reduction of teeth starting posteriorly, and patients with complete dental arch (Complete DA) (n = 34). The group of patients whit SDA was divided among PPR wears (PPD + SDA) (n = 17) and non-wears (n = 43). The population of this study consisted on patients who received or looked for treatment at the clinics of the Department of Dentistry of UFRN, from clinical analysis and records. The sample was chosen by convenience. For statistical analysis, it was a database in SPSS 17.0, followed by descriptive analysis with frequencies, absolute values, tests of central tendency and variability. The statistical tests used were chi-squared and analysis of variance as well as Tukey s post test, when applicable, all with a 95% confidence level. The results shown a prevalence of TMD of 47,1% among patients using PRP and 69,8% among those who didn t, but this result wasn t statistically significant. The mean of the results of masticatory efficiency, WHOQOL and OHIP didn t show association to the presence or absence of PPR and to the lower number of occlusal units of the patients (0, 1, 2 or more occlusal). The association only occurred among the different groups of SDA and the patients with complete dental arch. Taking into account the results, it could be observed that studied patients with low posterior support using lower PRP didn t have better masticatory efficiency, general quality of life, less impacts of their oral conditions in quality of life or not even less temporomandibular dysfunction or better masticatory efficiency when compared to those who didn t use the prosthesis