94 resultados para Scalling and root planning


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The main goal of this study was to identify and analyse environmental problems related to human occupation at the south part of the city of Paranagua PR, Brazil, aiming the diagnosis and conceptual evaluation of landscape use. For landscape use assessments and degradation diagnosis purposes, the environment was classified considering mainly geological and geomorphologic characteristics, such as declivity and sediment origin. The identification of potential environmental impacts was made by aerial photographs, Landsat-TM images, photographic records, surface sediment samples, water-column samples, and mainly observation visits to each classified unit. Surface sediment samples were taken with a Petit-Ponar sampler, in 13 station located in Paranagua Bay. In order to characterize the contamination level on sediments, the concentration of the following elements were analysed: arsenic (As), copper (Cu), cadmium (Cd), nickel (Ni), lead (Ph) e zinc (Zn). For the extraction of these elements, samples were treated with HCl 0.1N for 12 hours. This method has the advantage of determining contaminants which are weakly bind to the sediment, thus more available to the system. Analysis were performed by atomic absorption spectroscopy. According to the adopted criteria, sectors were classified as hills, mangroves, continental sediments and beach ridges urban and port industrial. Water quality and concentrations of metallic elements were determined at three sectors one control and two with the influence of urban and port/industrial activities, respectively the major upland impacts found were: deforestation due to disordered occupation, and solid waste emission through domestic and industrial sewage. The diagnosis of the actual situation was used as a basis for a management plan, once it allows the identification of impacts, and consequent environmental irregularities. Based on this considerations, suggestions for land use and management were presented, which offers a better approach for recuperation and protection of the studied ecosystem.

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Starches from six different species (cassava, arrowroot, sweet potato, yam, canna and ginger) were isolated and some structural and physicochemical characteristics analysed and correlated. Phosphorous and amylose contents were determined using a colorimetric method and measuring iodine affinity, respectively. Molecular weight distributions of starches were analysed by Sepharose CL 2B. Granular shape and size distribution were performed using an image analyser system attached to a light microscope. Swelling power was determined at 60, 70, 80 and 90 degrees C. Pasting and thermal properties were measured using a rapid viscoanalyser, and a differential scanning calorimeter, respectively. Phosphorous content varied from 0.007 to 0.031% for cassava and canna starches, respectively. Yam, canna and ginger starches displayed higher amylose contents (32.6, 31.7 and 26.5%, respectively) than cassava, arrowroot and sweet potato starches (19.8, 20.8 and 22.6%, respectively). These last three starches displayed amylose molecules of higher molecular weight than those shown for yam, canna and ginger starches. Canna starch showed higher proportions of longer branch chains of amylopectin than others starches. The size and shape of granules were quite variable among all starches and the average size of granules varied from 13.9 to 42.3 mu m for sweet potato and canna, respectively. Swelling power, pasting, and thermal properties were affected by structural characteristics of the starches.

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The usefulness of the application of heuristic algorithms in the transportation model, first proposed by Garver, is analysed in relation to planning for the expansion of transmission systems. The formulation of the mathematical model and the solution techniques proposed in the specialised literature are analysed in detail. Starting with the constructive heuristic algorithm proposed by Garver, an extension is made to the problem of multistage planning for transmission systems. The quality of the solutions found by heuristic algorithms for the transportation model is analysed, as are applications in problems of planning transmission systems.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Report some of the changes in production and consumption occurring in the state of São Paulo. through the restructuring in motion systems, logistics and standards and taxation, as well as the impacts on urban spaces through new economic dynamics, imposed by the demands of corporate, is the purpose of this article. The decentralization of production and consumption towards the interior was made possible by the combination of hierarchical and ordered some basic elements such as technological innovations (ways and means of transport) and organizational (logistics, standards and taxation) which optimized the flow territorial state São Paulo. It is noteworthy, therefore: 1) the improvement of logistics as a strategy, planning and management of transport, storage and communications (including the granting of public services to private), 2) the technological improvement and expansion of motion systems (infrastructure, means of transport) and 3) the systems of rules and regulations through taxation and deregulation affect the circulatory system of a given space. Thus, both systems aims to disentangle the economic flows (goods, services, information, capital and people) and provide a more fluid territorial. The impacts on the State of São Paulo, mainly through its economic dynamics, revert positively and negatively, by changing the way one thinks and performs planning.

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A case report of the treatment of permanent incisors with crown and root fractures is presented. A radiolucent lesion at the fracture lines was treated with calcium hydroxide in the coronal fragments for 18 months. Clinically, the teeth became firm and the radiographic results after 2 years showed healing of the lesion and hard tissue filling in the space at the fracture lines. © Munksgaard, 2001.

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The aim of this study was to analyze, under scanning electron microscopy (SEM), the morphologic characteristics of root surfaces after application of CarisolvTM gel in association with scaling and root planing (SRP). Sixty periodontally compromised extracted human teeth were randomly assigned to 6 groups: 1) SRP alone; 2) passive topical application of CarisolvTM + SRP; 3) active topical application of CarisolvTM + SRP; 4) multiple applications of CarisolvTM + SRP; 5) SRP + 24% EDTA; 6) topical application of CarisolvTM + SRP + 24% EDTA. CarisolvTM gel was applied to root surfaces for 30 s, followed by scaling and root planing, consisting of 50 strokes with Gracey curettes in an apical-coronal direction, parallel to the long axis of the tooth. The only exception was group 4, in which the roots were instrumented until a smooth, hard and glass-like surface was achieved. All specimens were further analyzed by SEM. The results showed that the treatment with CarisolvTM caused significant changes in root surface morphology of periodontally compromised teeth only when the chemical agent was actively applied (burnishing technique). CarisolvTM failed to remove the smear layer completely, especially with a single application, independently of the method of application. Multiple applications of CarisolvTM were necessary to achieve a smear layer reduction comparable to that obtained with 24% EDTA conditioning.

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The purpose of this study was to evaluate the effectiveness of subgingival application of Carisolv™ gel as an adjunctive therapy to scaling and root planing (SRP) on calculus removal compared to conventional instrumentation. Forty-five teeth requiring extraction due to severe periodontal disease were randomized to the following treatments: 1) SRP alone; 2) placebo gel + SRP; 3) Carisolv™ gel + SRP. Either test or placebo gel was applied subgingivally for 1 min and then the root were instrumented until a smooth and calculus-free surface was achieved. Instrumentation time and the number of strokes required were recorded. After extraction, the efficacy of root surface instrumentation was measured by percentage of remaining calculus. There was no statistically significant difference (p>0.05) between the treatment groups regarding either time required for instrumentation or the percentage of residual calculus. The subgingival application of Carisolv™ gel prior to SRP did not provide any additional benefit to root instrumentation compared to scaling and root planing alone.

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Negative effects of soil compaction have been recognized as one of the problems restricting the root system and consequently impairing yields, especially in the Southern Coastal Plain of the USA. Simulations of the root restricting layers in green house studies are necessary for the development of mechanism which alleviates soil compaction problems in these soils. The selection of three distinct bulk densities based on the standard proctor test is also an important factor to determine which bulk density restricts the root layer. The experiment was conducted to assess the root length density and root diameter of the corn (Zea mays L.) crop as a function of bulk density and water stress, characterized by the soil density (1.2; 1.4, and 1.6 g cm -3), and two levels of the water content, approximately (70 and 90% field capacity). The statistical design adopted was completely randomized design, with four replicates in a factorial pattern of (3 × 2). The PVC tubes were superimposed with an internal diameter of 20 cm with a height of 40 cm (the upper tube 20 cm, compacted and inferior tube 10 cm), the hardpan with different levels of soil compaction were located between 20 and 30 cm of the depth of the pot. Results showed that: the main effects of subsoil mechanical impedance were observed on the top layer indicating that the plants had to penetrate beyond the favorable soil conditions before root growth was affected from 3.16; 2.41 to 1.37 cm cm -3 (P<0.005). There was a significant difference at the hardpan layer for the two levels of water and 90% field capacity reduced the root growth from 0.91 to 0.60 cm cm -3 (P<0.005). The root length density and root diameter were affected by increasing soil bulk density from 1.2 to 1.6 g cm -3 which caused penetration resistance to increase to 1.4 MPa. Soil water content of 70% field capacity furnished better root growth in all the layers studied. The increase in root length density resulted in increased root volume. It can also be concluded that the effect of soil compaction impaired the root diameter mostly at the hardpan layer. Soil temperature had detrimental effect on the root growth mostly with higher bulk densities.

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The purpose of this study was to evaluate the influence of coronal leakage on the healing of dogs' periapical tissues after root canal filling, post space preparation and protection or not with a temporary sealer plug. Forty root canals of dogs' teeth were instrumented and filled by the lateral condensation technique with gutta-percha points and Endomethasone or CRCS sealers. After post space preparation, the remaining filling material was protected or not with a plug of temporary Coltosol sealer and exposed to the oral environment for 90 days. Thereafter, the animals were sacrificed and the specimens were removed and prepared for histomorphological and histobacteriological analysis. The findings revealed 35% of microbial leakage in the groups without plugs and 15% of leakage in the groups with plugs. Statistical analysis showed that the use of a Coltosol plug improved significantly the histomorphological results regardless of the type of root canal sealer (p=0.05) and that CRCS and Endomethasone sealers showed similar results (p>0.05).

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Aim: Smear layer removal and collagen fiber exposure may improve periodontal treatment and regeneration. This in vitro study assessed smear layer removal and collagen fiber exposure after tetracycline hydrochloride (TTC) application on root surfaces using scanning electron microscopy (SEM). Methods and Materials: Root cementum was removed with diamond burs followed by scaling and root planning. Four hundred fifty samples were divided into ten groups: a control (saline application) and nine different TTC concentrations were applied at doses of 10, 25, 50, 75, 100, 125, 150, 200, and 250 mg/ml. The TTC application was performed in all groups in three different ways (passive, brushing, and burnishing) and at three different periods of conditioning (1, 2, and 3 minutes). A previously trained, calibrated, and blind examiner evaluated photomicrographs of the samples using Sampaio's index (2005). Statistical analysis was performed using the Kruskal-Wallis' and Dunn's tests. Results: The concentrations of 50 mg/mL and 75 mg/mL applied by burnishing were the most effective in smear layer removal and collagen fiber exposure. Both the passive mode of application (p=0.0001) and 1 minute period of application (p=0.002) were the least effective. Conclusions: The concentrations of 50 mg/mL and 75 mg/mL applied by burnishing during 2 or 3 minutes were the most effective. Clinical Significance: These parameters may be applied in periodontal procedures involving TTC root conditioning to optimize results.

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Soil compaction reduces root growth, affecting the yield, especially in the Southern Coastal Plain of the USA. Simulations of the root restricting layers in greenhouses are necessary to develop mechanisms which alleviate soil compaction problems. The selection of three distinct bulk densities based on the Standard Proctor Test is also an important factor to determine which bulk density restricts root penetration. This experiment was conducted to evaluate cotton (Gossypium hirsutum L.) root volume and root dry matter as a function of soil bulk density and water stress. Three levels of soil density (1.2, 1.4, and 1.6 g cm-3), and two levels of water content (70 and 90% of field capacity) were used. A completely randomized design with four replicates in a 3×2 factorial pattern was used. The results showed that mechanical impedance affected root volume positively with soil bulk density of 1.2 and 1.6 g cm-3, enhancing root growth (P>0.0064). Soil water content reduced root growth as root and shoot growth was higher at 70% field capacity than that at 90% field capacity. Shoot growth was not affected by the increase in soil bulk density and this result suggests that soil bulk density is not a good indicator for measuring mechanical impedance in some soils.

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Lumiracoxib is a selective inhibitor of cyclooxygenase-2 (COX-2) approved for the relief of symptoms of chronic inflammatory conditions. The aim of this study was to evaluate the effects of this specific inhibitor of COX-2 as adjunctive treatment on induced periodontitis in rats. Periodontal disease was induced at the first mandibular molar of 60 rats. After 7 days, the ligature was removed and all animals were submitted to scaling and root planing (SRP) along with local irrigation with saline solution and were divided into 2 groups: SRP (n = 30)-received subcutaneous injections of 1 mg/kg of body weight/day of saline solution for 3 days and; SRP + L (n = 30)-received subcutaneous injections of 1 mg/kg of body weight/day of Lumiracoxib for 3 days. Ten animals in each group were killed at 7, 15, and 30 days. The histological description was performed and the histometric values were statistically analyzed. In Group SRP + L, the histometric analysis (0.58 ± 0.08, 0.64 ± 0.06, and 0.56 ± 0.10 mm 2) showed less bone loss (p < 0.05) than Group SRP (1.52 ± 0.08, 1.55 ± 0.09, and 1.49 ± 0.24 mm 2) at 7, 15, and 30 days, respectively. Within the limits of this study it can be concluded that subcutaneous application of specific inhibitor of COX-2 was a beneficial adjunctive treatment for periodontal diseases induced in rats. © 2010 Springer Basel AG.

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The aim of this paper was to evaluate two surface conditioning methods associated with the application of adhesive on the post surface for improving the bond to resin cement. Sixty single-rooted bovine teeth were sectioned at 16 mm in length, prepared (9 mm depth), embedded in a PVC cylinder using acrylic resin, and allocated into 3 groups (N.=20) according to post surface treatment: cleaning with ethanol (control group); etching with hydrogen peroxide; etching with hydrofluoric acid. Ten posts for each group were silanized and other 10 posts were silanized and received an adhesive agent. The posts were cemented with self-adhesive resin cement (RelyX U100 resin cement). All teeth were sectioned perpendicularly to the long axis (2 mm thickness per slice), submitted to push out bond strength testing and the type of failure was recorded. The obtained data were submitted to two-way ANOVA and Turkey's test, with the level of significance set at 5%. Neither the hydrofluoric acid or hydrogen peroxide post surface treatment, nor the adhesive application, had an influence on bond strength values. The main type of failure was adhesive between cement and dentin. Etching and the application of an adhesive on the post surface did not presented a significant influence on the bond strength results for the fiber post resin cement-root dentin assembly. The cement appears to adhere very well to the fiber post surface rather than the dentin surface.