921 resultados para Dent Texture
Resumo:
Spray-dried blood plasma (DBP) (10.9 g/100 g [w/w] nitrogen) was added to medium-protein biscuit flour (1.4 g/100 g N) during pasta manufacture. High-protein durum semolina (2.0 g/100 g N) Was used to produce the control pasta. Sensory data indicated that the addition of DBP produced pasta with significantly better colour intensity and acceptability. aroma intensity, flaN our intensity. textural strength, texture acceptability, aftertaste intensity, aftertaste acceptability. and overall acceptability The DBP/biscuit flour formulation that gave the optimum balance between pasta protein content and organoleptic acceptability contained 2.2 g/100 g DBP. A higher content of DBP resulted in increased protein levels, but these pasta formulations, ere less acceptable organoleptically. (C) 2002 Swiss Society of Food Science and Technology. Published by Elsevier Science Ltd. All rights reserved.
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The assumption in analytical solutions for flow from surface and buried point sources of an average water content, (θ) over bar, behind the wetting front is examined. Some recent work has shown that this assumption fitted some field data well. Here we calculated (θ) over bar using a steady state solution based on the work by Raats [1971] and an exponential dependence of the diffusivity upon the water content. This is compared with a constant value of (θ) over bar calculated from an assumption of a hydraulic conductivity at the wetting front of 1 mm day(-1) and the water content at saturation. This comparison was made for a wide range of soils. The constant (θ) over bar generally underestimated (θ) over bar at small wetted radii and overestimated (θ) over bar at large radii. The crossover point between under and overestimation changed with both soil properties and flow rate. The largest variance occurred for coarser texture soils at low-flow rates. At high-flow rates in finer-textured soils the use of a constant (θ) over bar results in underestimation of the time for the wetting front to reach a particular radius. The value of (θ) over bar is related to the time at which the wetting front reaches a given radius. In coarse-textured soils the use of a constant value of (θ) over bar can result in an error of the time when the wetting front reaches a particular radius, as large as 80% at low-flow rates and large radii.
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The electrochemical performance of carbon fibers (CF) and boron-doped diamond electrodes grown on carbon fiber substrate (BDD/CF) was studied. CF substrates were obtained from polyacrylonitrile precursor heat treated at two different temperatures of 1000 and 2000 degrees C to produce the desirable CF carbon graphitization index. This graphitization process influenced the CF conductivity and its chemical surface, also analyzed from X-ray photoelectron spectroscopy measurements. These three-dimensional CF structures allowed a high incorporation of diamond films compared to other carbon substrates such as glass carbon or HOPG. The electrochemical responses, from these four classes of electrodes, were evaluated focusing their application as electrical double-layer capacitors using cyclic voltammetry and impedance measurements. Cyclic voltammetry results revealed that the electrode formed from BDD grown on CF-2000 presented a typical capacitor behavior with the best rectangular shape, compared to those electrodes of CF or BDD/CF-1000. Furthermore, the BDD/CF-2000 electrode presented the lowest impedance, associated to its significant capacitance value of 1940 mu F/cm(2) taking into account the BDD films. This behavior was attributed to the strong dependence between diamond coating texture and the CF graphitization temperature. The largest surface area of BDD/CF-2000 was promoted by its singular film growth mechanism associated to the substrate chemical surface. (c) 2008 Elsevier B.V. All rights reserved.
Resumo:
This paper describes the construction of Australia-wide soil property predictions from a compiled national soils point database. Those properties considered include pH, organic carbon, total phosphorus, total nitrogen, thickness. texture, and clay content. Many of these soil properties are used directly in environmental process modelling including global climate change models. Models are constructed at the 250-m resolution using decision trees. These relate the soil property to the environment through a suite of environmental predictors at the locations where measurements are observed. These models are then used to extend predictions to the continental extent by applying the rules derived to the exhaustively available environmental predictors. The methodology and performance is described in detail for pH and summarized for other properties. Environmental variables are found to be important predictors, even at the 250-m resolution at which they are available here as they can describe the broad changes in soil property.
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Reconstruction of the nipple-areola complex (NAC) is the last stage of breast reconstruction and represents the search for symmetry in regard to the contralateral breast. The objective of this study was to present an areola reconstruction technique with local skin graft to improve the texture and aspect of the reconstructed areola, searching for a natural look. This technique was performed on 122 patients who in the period from January 2000 to December 2005 were submitted to nipple and areola reconstruction. Once the position of the new nipple was determined, markings were made for the reconstruction of the areola. Then the external limit of the new areola was incised and the skin was centripetally deepidermized up to 85% of its diameter. After this procedure the detached skin was repositioned in its bed as a graft and sutured with 4.0 mononylon thread. Incisions with an 11-blade scalpel were then made in V and C forms associated with the detachment of this skin of the receptor area along the local graft so that at the end of the healing process they would determine alterations in the areolar texture mimicking the texture of a normal areola. All patients underwent tattooing 3 months after reconstruction of the NAC taking into account the different shades of the contralateral areola and nipple colors. The use of a local skin graft associated with C and V incisions allowed alteration in the texture of the reconstructed areola. The use of different ink shades for tattooing helped to give a tridimensional aspect to this areola. These factors determined a good aesthetic result in these patients. This areola reconstruction using a local skin graft allows change in the areola texture and a tridimensional aspect similar to that of a normal areola without the inconvenience of grafting from a distance.
Resumo:
Soil structure is generally defined as the arrangement, orientation, and organization of the primary particles of sand, silt, and clay into compound aggregates, which exhibit properties that are unequal to the properties of a mass of nonaggregated material with a similar texture.6 Therefore the nature of soil structure is that it conveys specific properties to the soil and any alteration, i.e., breakdown or structural development, to the soil structural units will affect the physical properties of the soil. The aggregation and organization of the soil particles tend to form a hierarchical order4, 5 where the lower orders tend to have higher densities and greater internal strength than the higher orders. A schematic diagram of the hierarchical nature of soil structural elements in a clay soil is given in Fig. 1.4 Clay particles tend to form domains (packets of parallel clay sheets, generally consisting of 5-7 sheets), in turn several domains form clusters, followed by several orders of clusters, micro- and macroaggregates. The hierarchical nature implies that the destruction of a lower order will result in the destruction of all higher hierarchical orders. An example is the dispersion of sodic clay domains which results in the destruction of all higher orders, resulting in a dense soil with low hydraulic conductivity. Hence the clay domains are the fundamental building blocks of the soil and its integrity may determine the soil's physical properties and behavior.
Resumo:
Forty-five children (31 boys and 14 girls), aged 6-11 years, were included in the study, 15 with a skeletal anterior open bite (SAOB), 15 with a dentoalveolar anterior open bite (DAOB), and 15 with a normal occlusion (CG), defined by clinical evaluation and lateral cephalograms. EMG recordings of the temporal and masseter muscles were performed under maximal voluntary clenching and during chewing. Analysis of variance was used for inter-group analysis, followed by the Tukey post hoc test. A Student`s t-test for paired data was used for intra-group analysis. There were statistically significant differences among the three groups (P < 0.05), with the mean EMG being highest in the CG and lowest in children with a SAOB. The percentage EMG activity during chewing in relation to that during maximal voluntary clenching was more than 100 per cent in the SAOB group. The CG and DAOB groups presented higher EMG activity during clenching compared with chewing (P < 0.001), as well as a greater difference between tasks. In the SAOB group, the neuromuscular system appeared to have a lower capacity to produce EMG activity according to the task, while that in the DAOB group suggests that their functional capacity during growth should also be carefully observed.
Resumo:
Purpose: To investigate the effects of intrapulpal temperature changes induced by a quartz tungsten halogen (QTH) and a light emitting diode (LED) curing units on the metabolism of odontoblast-like cells. Methods: Thirty-six 0.5 mm-thick dentin discs obtained from sound human teeth were randomly assigned into three groups: QTH, LED and no light (control). After placement of the dentin discs in pulp chamber devices, a thermistor was attached to the pulpal surface of each disc and the light sources were applied on the occlusal surface. After registering the temperature change, odontoblast-like cells MDPC-23 were seeded on the pulpal side of the discs and the curing lights were again applied. Cell metabolism was evaluated by the MTT assay and cell morphology was assessed by SEM. Results: In groups QTH and LED the intrapulpal temperature increased by 6.4 degrees C and 3.4 degrees C, respectively. The difference between both groups was statistically significant (Mann-Whitney; P< 0.05). QTH and LED reduced the cell metabolism by 36.4% and 33.4%, respectively. Regarding the cell metabolism, no statistically significant difference was observed between both groups (Mann-Whitney; P> 0.05). However, when compared to the control, only QTH significantly reduced the cell metabolism (Mann-Whitney; P< 0.05). It was concluded that the irradiance of 0.5 mm-thick human dentin discs with a QTH in comparison to a LED curing unit promoted a higher temperature rise, which propagates through the dentin negatively affecting the metabolism of the underlying cultured pulp cells. (Am J Dent 2009;22:151-156).
Resumo:
For some surgical procedures in veterinary dentistry including exodontia, orthognathic surgery, orthopedic surgery, oncologic surgery, and for the placement of dental implants, it is important to know the accurate location of the neurovascular structures within the mandibular canal. The aim of this research was to determine the course of the mandibular canal in the mandible and its relationship with other anatomical structures in brachycephalic dogs using computerized tomography. Mandibles from 10 brachycephalic cadaver dogs were evaluated. Measurements were taken in relation to the lingual, vestibular alveolar crest, and ventral surfaces. These measurements indicated that the mandibular canal descends slightly from the mandibular foramen to the molar area, decreasing the distance of the mandibular canal from the mandibular ventral border The mandibular canal is slightly closer to the lingual surface than the vestibular surface except in the molar tooth region. The mandibular canal continues in a rostral direction occupying the ventral region of the mandibular body, reaching its maximum distance from the alveolar crest at the level of the first molar and fourth premolar teeth. In the third and fourth premolar tooth region, the mandibular canal maintains a similar distance between the vestibular and lingual borders; then, at the level of the second premolar tooth, the distance of the mandibular canal from the lingual and ventral border increases before its termination at the mental, foramen. The study reported here documents the feasibility of using CT to determine the location of the mandibular canal in relation to bony and dental parameters. Although the difference in mandible size of the group of brachycephalic dogs reported here resulted in broad ranges of measurements, it is clear that the MC course may vary between individual dogs. J Vet Dent 26(3); 156 - 163, 2009
Resumo:
This study aimed to develop a plate to treat fractures of the mandibular body in dogs and to validate the project using finite elements and biomechanical essays. Mandible prototypes were produced with 10 oblique ventrorostral fractures (favorable) and 10 oblique ventrocaudal fractures (unfavorable). Three groups were established for each fracture type. Osteosynthesis with a pure titanium plate of double-arch geometry and blocked monocortical screws offree angulanon were used. The mechanical resistance of the prototype with unfavorable fracture was lower than that of the fcworable fracture. In both fractures, the deflection increased and the relative stiffness decreased proportionally to the diminishing screw number The finite element analysis validated this plate study, since the maximum tension concentration observed on the plate was lower than the resistance limit tension admitted by the titanium. In conclusion, the double-arch geometry plate fixed with blocked monocortical screws has sufficient resistance to stabilize oblique,fractures, without compromising mandibular dental or neurovascular structures. J Vet Dent 24 (7); 212 - 221, 2010
Resumo:
The objective of this research was to evaluate the effects of 2 levels of raw milk somatic cell count (SCC) on the composition of Prato cheese and on the microbiological and sensory changes of Prato cheese throughout ripening. Two groups of dairy cows were selected to obtain low-SCC (<200,000 cells/mL) and high-SCC (>700,000 cells/mL) milks, which were used to manufacture 2 vats of cheese. The pasteurized milk was evaluated according to the pH, total solids, fat, total protein, lactose, standard plate count, coliforms at 45 degrees C, and Salmonella spp. The cheese composition was evaluated 2 d after manufacture. Lactic acid bacteria, psychrotrophic bacteria, and yeast and mold counts were carried out after 3, 9, 16, 32, and 51 d of storage. Salmonella spp., Listeria monocytogenes, and coagulase-positive Staphylococcus counts were carried out after 3, 32, and 51 d of storage. A 2 x 5 factorial design with 4 replications was performed. Sensory evaluation of the cheeses from low- and high-SCC milks was carried out for overall acceptance by using a 9-point hedonic scale after 8, 22, 35, 50, and 63 d of storage. The somatic cell levels used did not affect the total protein and salt: moisture contents of the cheeses. The pH and moisture content were higher and the clotting time was longer for cheeses from high-SCC milk. Both cheeses presented the absence of Salmonella spp. and L. monocytogenes, and the coagulase-positive Staphylococcus count was below 1 x 10(2) cfu/g throughout the storage time. The lactic acid bacteria count decreased significantly during the storage time for the cheeses from both low- and high-SCC milks, but at a faster rate for the cheese from high-SCC milk. Cheeses from high-SCC milk presented lower psychrotrophic bacteria counts and higher yeast and mold counts than cheeses from low- SCC milk. Cheeses from low- SCC milk showed better overall acceptance by the consumers. The lower overall acceptance of the cheeses from high-SCC milk may be associated with texture and flavor defects, probably caused by the higher proteolysis of these cheeses.
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Causes of dental infections can be related to failed dental eruption, malocclusion, abrasion, fractures with or without exposure of the dental pulp, and periodontal disease. Reports of oral myiasis in megavertebrates in captivity air infrequent, perhaps due to the difficulty in observing the oral cavity in such species. This report describes a case of oral myiasis in an adult male hippopotamus in the gingival area and alveolar mucosa of the left mandibular canine tooth. J Vet Dent 26 (3); 168 170,2009
Resumo:
Purpose: To assess the effects of three different dental adhesive systems on the formation of secondary root caries, in vitro, with a standardized interfacial gap in a filled cavity model. Methods: 40 sound human molars were selected and randomly assigned to four experimental groups: Clearfil SE Bond (CSEB), Xeno III (X-III), Scotchbond Multi-Purpose Plus (SBMP) and negative control (NC) without an adhesive system. After the standardized Class V cavity preparations on the buccal and lingual surfaces, restorations were placed with resin composite (Filtek Z250) using a standardized interfacial gap, using a 3 x 2 mm piece of 50 mu m metal matrix. The teeth were sterilized with gamma irradiation and exposed to a cariogenic challenge using a bacterial system with Streptococcus mutans. Depth and extension of wall lesions formed and the depth of outer lesions were measured by software coupled with light microscopy. Results: For wall lesion extension the ANOVA test showed differences between groups except between X-HI and SBMP (P= 0.294). The Tukey`s test of confidence intervals indicated smaller values for the CSEB group than for the others. For wall lesion depth the CSEB group also presented the smallest mean values of wall lesion depth when compared to the others (P< 0.0001) for all comparisons using Tukey`s test. Regarding outer lesion depth, all adhesives showed statistically similar behavior. SEM evaluation of the morphologic appearance of caries lesions confirmed the statistical results showing small caries lesion development for cavities restored with CSEB adhesive system, which may suggest that this adhesive system interdiffusion zone promoted a good interaction with subjacent dentin protecting the dental tissues from recurrent caries. (Am J Dent 2010;23:93-97).
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Background: Newly formed biofilm after implant debridement may challenge the long-term stability of peri-implant therapy. This in vitro study aimed to assess the roughness and adherence of Streptococcus sanguinis after treatment of smooth and rough titanium surfaces with an erbium-doped: yttrium, aluminum, and garnet (Er:YAG) laser, metal and plastic curets, and an air-powder abrasive system. Methods: Forty titanium disks with smooth-machined surfaces and 40 with sand-blasted and acid-etched surfaces were divided into the following treatment groups: Er:YAG laser; plastic curet; metal curet, and air-powder abrasive system. The surface roughness (roughness average [Raj) before and after treatments was determined using a profilometer. S. sanguinis (American Type Culture Collection 10556) was grown on treated and untreated specimens, and the amounts of retained bacteria on the surfaces were measured by the culture method. Rough and smooth surfaces with and without a suspension of S. sanguinis were also analyzed using scanning electron microscopy (SEM). Results: For smooth surfaces, the roughest surfaces were produced by metal curets (repeated - measures analysis of variance [ANOVA] and Tukey test; P<0.05). The rough-surface profile was not altered by any of the treatments (repeated-measures ANOVA; P>0.05). Rough surfaces treated with metal curets and air-powder abrasion showed the lowest level of bacteria] adhesion (two-way ANOVA and Tukey test; P<0.05). SEM analysis revealed distinct surface profiles produced by all devices. Conclusions: Metal curets are not recommended for smooth titanium surface debridement due to severe texture alteration. Rough surfaces treated with a metal curet and the air-powder abrasive system were less susceptible to bacterial adhesion, probably due to texture modification and the presence of abrasive deposits. J Periodontol 2009;80: 1824-1832.
Resumo:
Purpose: To evaluate the qualitative and quantitative differences on dental plaque formation on two different roughness titanium implant surfaces, i.e. machined and titanium plasma sprayed, as well as the amount of plaque removal by regular toothbrushing after 72-hour plaque accumulation. Methods: Eight systemically healthy subjects were recruited from the patient pool of a private dental practice. All patients underwent oral hygiene instruction and full mouth prophylaxis. Subsequently, maxillary casts from all patients were obtained and removable 0.7 mm-thick acetate stents without occlusal contact points were fabricated to support four titanium specimens of 4x2x2 mm divided into two groups (machined and plasma sprayed). Subjects were instructed to wear the stents for 72 hours, full time, removing them only during regular oral hygiene. Subsequently, the appliances were immediately repositioned and then the test side was brushed for 20 seconds. At the end of the 72-hour period, the stents were removed and prepared for microbiological analysis. Results: Both machined and plasma sprayed brushed surfaces presented statistically significant fewer bacteria than non-brushed surfaces. Similarly, regarding surface roughness, machined surfaces presented a total number of bacteria significantly smaller than those presented by plasma sprayed surfaces (P< 0.05). Statistically, the non-brushed machined turned surfaces presented a greater amount of Streptoccocus sp. when compared to the brushed machined surfaces. It was concluded that rough surfaces accumulated more dental plaque than polished surfaces. Both brushed surfaces presented less plaque accumulation, however, implant brushing was more effective on machined surfaces. (Am J Dent 2008;21:318-322).