40 resultados para Periodonto - Regeneração
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
heterogeneous catalyst such as a silicoaluminophosphate, molecular sieve with AEL (Aluminophosphate eleven) structure such as SAPO-11, was synthesized through the hydrothermal method starting from silica, pseudoboehmite, orthophosphoric acid (85%) and water, in the presence of a di-isopropylamine organic template. For the preparation of SAPO-11 in a dry basis it was used as reactants: DIPA; H3PO4; SiO4; Pseudoboehmite and distilled water. The crystallization process occurred when the reactive hydrogel was charged into a vessel and autoclaved at 200ºC for a period of 72 hours under autogeneous pressure. The obtained material was washed, dried and calcined to remove the molecular sieves of DIPA. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), nitrogen adsorption (BET) and thermal analysis (TG/DTG). The acidic properties were determined using adsorption of nbutylamine followed by programmed thermodessorption. This method revealed that SAPO-11 shows an acidity that ranges from weak to moderate. However, a small quantity of strong acid sites could be detected there. The deactivation of the catalysts was conducted by artificial coking followed by the cracking of the n-hexane in a fixed bed with a continuous flow micro-reactor coupled on line to a gas chromatograph. The main products obtained were: ethane, propane, isobutene, n-butane, n-pentane and isopentane. The Vyazovkin (model-free) kinetics method was used to determine the regeneration and removal of the coke
Resumo:
Different types of heterogeneous catalysts of the silicoaluminophosphate type, (SAPO-5, SAPO-11, SAPO-31, SAPO-34 and SAPO-41), molecular sieves with a: AFI, AEL, ATO, CHA and AFO structure, respectively, were synthesized through the hydrothermal method. Using sources such as hydrated alumina (pseudobohemita), phosphoric acid, silica gel, water, as well as, different types of organic structural templates, such as: cetyltrimethylammonium bromide (CTMABr), di-isopropylamine (DIPA), di-n- propylamine (DNPA) and tetraethylammonium hydroxide (TEOS), for the respective samples. During the preparation of the silicoaluminophosphates, the crystallization process of the samples occurred at a temperature of approximately 200 ° C, ranging through periods of 18-72 h, when it was possible to obtain pure phases for the SAPOs. The materials were furthermore washed with deionized water, dried and calcined to remove the molecules of the templates. Subsequently the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectroscopy in the infrared region (FT-IR), specific surface area and thermal analysis via TG/DTG. The acidic properties were determined using adsorption of n-butylamine followed by programmed termodessorption. These methods revealed that the SAPO samples showed a typically weak to moderate acidity. However, a small amount of strong acid sites was also detected. The deactivation of the catalysts was conducted by artificially coking the samples, followed by n-hexane cracking reactions in a fixed bed with a continuous flow micro-reactor coupled on line to a gas chromatograph. The main products obtained were: ethane, propane, isobutene, n-butane, n-pentane and isopentane. The Vyazovkin (model-free) kinetics method was used to determine the catalysts regeneration and removal of the coke
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Resumo:
In the late 1970s, the semi-arid region of Rio Grande do Norte was the setting of Projeto Baixo-Açu whose highlight was the building of the dam Eng. Armando Ribeiro Gonçalves, designed to collect 2.4 billion cubic meters of water. Presumably, such an initiative would bring economic and social development for thousands of potiguares who suffered the hardships of drought. However, the dam would reach several cities in the region, reaching to cover one of them: São Rafael. As a result, the early years of the 1980s, nearby, a new town was built by DNOCS. This thesis aims to discuss how the population of São Rafael recalls this fact and reconstructs its history by speaking, writing and computing, after three decades. Based on the prospect moriniana method as a strategy, visits were made to the city of São Rafael and open interviews (individual and collective) with two groups of subjects: one composed of those who lived in their ancient homeland, and another, with young people who were born in the new city. Besides the reports of these subjects, they were observed the visual narratives presented by images, mostly photographic, available on a profile created for the city in the orkut social network. As sources for this study, they were also considered the dialogues between rafaelenses accessing the above profile. Having as a central observation by Edgar Morin about what does not regenerate, degenerates . This study is the central argument that the idea of orkut has performed, today, a dual and interdependent role: being a tool that promotes a collective intelligence through cooperation, exchange of ideas and reconstitution of visual and written narratives. Far from a frozen conception in a historical perspective, it has defended the thesis that orkut has regenerated, repaired, reproduced, restored, reorganized and renewed the memory and history of a city that has succumbed to the immensity of the waters of a dam for almost thirty years
Resumo:
This study clinically evaluated the relationship of gingival recessions with the periodontal index of gingival and plaque, dental alignment, keratinized mocous, type of periodontal, and occlusal disorders. Study participants were individuals aged between 19 and 33 years. The evaluations were performed by using questionnaires and clinical examinations. In subjects examined, the teeth were assessed and divided into groups (Molars, premolars, canines and incisors). The gingival recession were measured in the central region of the teeth and individuals were subject to disclosure to the plate and observing the poll of plaque and gingival index, respectively. 558 teeth were examined, with 24.1%, 135 had gingival recession greater than or equal to 1mm. Through the combination of tests used to evaluate the average of the recession and its relationship with the variables studied, we observed that the degree of recession of the elements assessed dental showed, almost for the most part, when higher values associated with the index plaque (p = 0.101), Gingival Index (p = 0.053), dental alignment (p = 0.962), width of keratinized mocous (p = 0.004) and type of periodontium (p = 0.033), however statistically significant difference could only be considered when related the recessions in the keratinized mocous and the type of the periodontium. Although we identify, when we evaluate the whole set of teeth that occlusal disturbances (p = 0.002) were more strongly associated with cases of gum recession that the gingival index (p = 0.006), however, these two conditions were correlated with the cases of recession, contributing to its occurrence
Resumo:
The neurovascular system of the pulp and of the periodontium is interconnected and among the possible intercommunications between these two tissues, there is the cavo inter-radicular canal. It is a small canal that goes through any inter-radicular dentine and arises in the furca region of the multi-radicular teeth. Its predominance has been studied in the literature, by several methodologies, with divergent results. The objective of this work was to establish, in vitro, the predominance of the cavo inter-radicular canal, in human lower molars, through the diaphanization technique and dye leakage. For this research, 140 teeth (100 first and second 40 lower molars) were selected, extracted due to different reasons, belonging to a teeth bank of the Endodontics discipline of the Dentistry College at Federal University of Rio Grande do Norte. The teeth were preserved in formol until the moment of use and immersed in physiological solution. Had the endodontic access fulfilled and the whole external surface, except for the furcation, sealed with two layers of nail enamel. The cleaning of the pulpar chamber floor was carried out with sodium hypochlorite solution 5%, being this solution renewed every 5 minutes, during 1 hour. The teeth were immersed in Indian dye and, after drying of the dye, they had their crowns split up in the amelo-cemental junction. Then, they were examined in a stereomicroscope, where marks of the coloring were observed in the furcation and on the pulpar floor. After this recording, the sample was diaphanized and with the transparent teeth, it was possible to observe in the stereomicroscope, the true inter-radicular canals. As a result of this experiment, the presence of these canals was observed in 13 % of the first and 7, 5 % of the second evaluated molars. The study showed that both the presence of the cavo inter-radicular canal is real and the diaphanization and dye leakage is an efficient method for this type of research
Resumo:
The literature has shown a relation between periodontics and the removable partial denture (RPD), with progressive destruction observed in the support structures. The aim of this study was to clinically assess periodontal condition in users of removal partial denture (RPD), and compare right abutments teeth, indirect abutments and controls before installation and after 1 year, in addition to comparing tooth-supported and tooth mucosa-supported abutments. A total of 50 patients, 32 women and 18 men, mean age of 45 years, took part in the study. The patients were examined by a single examiner at prosthesis installation and after 3, 6, 9 and 12 months. The following were verified at each examination: Probe Depth (PD), Plaque Index (PI), Gingival Index (GI), the amount of Keratinized Mucosa (KM), Gingival Recession (GR) and Dental Mobility (DM); in addition patients received oral hygiene orientation, accompanied by prophylaxis, periodontal scaling and root planing (PSRP), when necessary. Analysis of Variance (ANOVA) with Tukey-Kramer post test was used to assess the dependent variables (PD, PI, KM, GR) of the three groups over time while Friedman s test was used for GI. To assess the outcomes of prosthesis type in the right abutment group, a confidence interval-based analysis was performed. The results showed that the control group was the least compromised in all the variables studied. With respect to development of the groups over time, it was verified that the measures for GR, PD, GI and KM increased from initial examination to 1 year of use in all the groups, but only PI showed a significant increase. There was a non-discriminatory low prevalence of dental mobility. The tooth mucosa-supported prosthesis had significantly higher values for GR, GI and PI and significantly lower ones for KM when compared to tooth-supported. Over time, both types of prostheses showed no significant differences from initial to final examination for the variables GR, PD, KM and GI, with PI significant only for tooth-supported. The results showed that the teeth most involved in RPD design had greater potential of periodontal damage, probably because of greater dental biofilm accumulation. Abutments elements adjacent to the free extremities had less favorable periodontal condition than those adjacent to interpolated spaces, but the use of RPD did not worsen the initial condition
Resumo:
Heterogeneous catalysts such as aluminophosphate and silicoaluminophosphate, molecular sieves with AEL of ALPO-11 and SAPO-11, were synthesized by the hydrothermal method with the following molar composition: 2.9 Al +3.2 P + 3.5 DIPA +32.5 H20 (ALPO-11); 2.9 Al +3.2 P + 0.5 Si + 3.5 DIPA +32.5 H20 (SAPO-11) starting from silica (only in the SAPO-11), pseudoboehmite, orthophosphoric acid (85%) and water, in the presence of a di-isopropylamine organic template. The crystallization process occurred when the reactive hydrogel was charged into a vessel and autoclaved at 170ºC for a period of 48 hours under autogeneous pressure. The obtained materials were washed, dried and calcined to remove the molecular sieves of DIPA. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), thermo gravimetric differential thermal analysis (TG/DTA) and nitrogen adsorption (BET). The acidic properties were determined using adsorption of n-butylamine followed by programmed thermodessorption. This method revealed that ALPO-11 has weaker acid sites due to structural defects, while SAPO-11 shows an acidity that ranges from weak to moderate. However, a small quantity of strong acid sites could be detected there. The deactivation of the catalysts was conducted by the cracking of the n-hexane in a fixed bed continuous flow microrreator coupled on line to a gas chromatograph. The main products obtained were: ethane, propane, isobutene, n-butane, n-pentane and isopentane. The Vyazovkin (model-free) kinetics method was used to determine the regeneration and removal of the organic template
Resumo:
heterogeneous catalyst such as a silicoaluminophosphate, molecular sieve with AEL (Aluminophosphate eleven) structure such as SAPO-11, was synthesized through the hydrothermal method starting from silica, pseudoboehmite, orthophosphoric acid (85%) and water, in the presence of a di-isopropylamine organic template. For the preparation of SAPO-11 in a dry basis it was used as reactants: DIPA; H3PO4; SiO4; Pseudoboehmite and distilled water. The crystallization process occurred when the reactive hydrogel was charged into a vessel and autoclaved at 200ºC for a period of 72 hours under autogeneous pressure. The obtained material was washed, dried and calcined to remove the molecular sieves of DIPA. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), nitrogen adsorption (BET) and thermal analysis (TG/DTG). The acidic properties were determined using adsorption of nbutylamine followed by programmed thermodessorption. This method revealed that SAPO-11 shows an acidity that ranges from weak to moderate. However, a small quantity of strong acid sites could be detected there. The deactivation of the catalysts was conducted by artificial coking followed by the cracking of the n-hexane in a fixed bed with a continuous flow micro-reactor coupled on line to a gas chromatograph. The main products obtained were: ethane, propane, isobutene, n-butane, n-pentane and isopentane. The Vyazovkin (model-free) kinetics method was used to determine the regeneration and removal of the coke
Resumo:
Different types of heterogeneous catalysts of the silicoaluminophosphate type, (SAPO-5, SAPO-11, SAPO-31, SAPO-34 and SAPO-41), molecular sieves with a: AFI, AEL, ATO, CHA and AFO structure, respectively, were synthesized through the hydrothermal method. Using sources such as hydrated alumina (pseudobohemita), phosphoric acid, silica gel, water, as well as, different types of organic structural templates, such as: cetyltrimethylammonium bromide (CTMABr), di-isopropylamine (DIPA), di-n- propylamine (DNPA) and tetraethylammonium hydroxide (TEOS), for the respective samples. During the preparation of the silicoaluminophosphates, the crystallization process of the samples occurred at a temperature of approximately 200 ° C, ranging through periods of 18-72 h, when it was possible to obtain pure phases for the SAPOs. The materials were furthermore washed with deionized water, dried and calcined to remove the molecules of the templates. Subsequently the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectroscopy in the infrared region (FT-IR), specific surface area and thermal analysis via TG/DTG. The acidic properties were determined using adsorption of n-butylamine followed by programmed termodessorption. These methods revealed that the SAPO samples showed a typically weak to moderate acidity. However, a small amount of strong acid sites was also detected. The deactivation of the catalysts was conducted by artificially coking the samples, followed by n-hexane cracking reactions in a fixed bed with a continuous flow micro-reactor coupled on line to a gas chromatograph. The main products obtained were: ethane, propane, isobutene, n-butane, n-pentane and isopentane. The Vyazovkin (model-free) kinetics method was used to determine the catalysts regeneration and removal of the coke
Resumo:
Human multipotent mesenchymal stromal cells (MSCs), also known as mesenchymal stem cells, have become an important and attractive therapeutic tool since they are easily isolated and cultured, have in vitro expansion potential, substantial plasticity and secrete bioactive molecules that exert trophic effects. The human umbilical cord as a cell source for cell therapy will help to avoid several ethical, political, religious and technical issues. One of the main issues with SC lines from different sources, mainly those of embryonic origin, is the possibility of chromosomal alterations and genomic instability during in vitro expansion. Cells isolated from one umbilical cord exhibited a rare balanced paracentric inversion, likely a cytogenetic constitutional alteration, karyotype: 46,XY,inv(3)(p13p25~26). Important genes related to cancer predisposition and others involved in DNA repair are located in 3p25~26. Titanium is an excellent biomaterial for bone-implant integration; however, the use can result in the generation of particulate debris that can accumulate in the tissues adjacent to the prosthesis, in the local bone marrow, in the lymph nodes, liver and spleen. Subsequently may elicit important biological responses that aren´t well studied. In this work, we have studied the genetic stability of MSC isolated from the umbilical cord vein during in vitro expansion, after the cryopreservation, and under different concentrations and time of exposition to titanium microparticles. Cells were isolated, in vitro expanded, demonstrated capacity for osteogenic, adipogenic and chondrogenic differentiation and were evaluated using flow cytometry, so they met the minimum requirements for characterization as MSCs. The cells were expanded under different concentrations and time of exposition to titanium microparticles. The genetic stability of MSCs was assessed by cytogenetic analysis, fluorescence in situ hybridization (FISH) and analysis of micronucleus and other nuclear alterations (CBMN). The cells were able to internalize the titanium microparticles, but MSCs preserve their morphology, differentiation capacity and surface marker expression profiles. Furthermore, there was an increase in the genomic instability after long time of in vitro expansion, and this instability was greater when cells were exposed to high doses of titanium microparticles that induced oxidative stress. It is necessary always assess the risks/ benefits of using titanium in tissue therapy involving MSCs, considering the biosafety of the use of bone regeneration using titanium and MSCs. Even without using titanium, it is important that the therapeutic use of such cells is based on analyzes that ensure quality, security and cellular stability, with the standardization of quality control programs appropriate. In conclusion, it is suggested that cytogenetic analysis, FISH analysis and the micronucleus and other nuclear alterations are carried out in CTMH before implanting in a patient
Resumo:
The destructive impact of improper disposal of heavy metals in the environment increases as a direct result of population explosion, urbanization and industrial expansion and technological developments. Argil are potential materials for adsorption of inorganic and the pelletization of it is required for use in adsorptive columns of fixed bed. The low cost and the possibility of regeneration makes these materials attractive for use in the purification process, capable of removing inorganic compounds in contaminated aquatic environments. In this work was made pellets of a mixture of dolomite and montmorillonite by wet agglomeration, in different percentages. The removal of Pb (II) was investigated through experimental studies, and was modeled by kinetic models and isotherms of adsorption. The materials were characterized using the techniques of XRD, TG / DTA, FT-IR, and surface area by BET method. The results showed the adsorption efficiency of the contaminant by the composite material studied in synthetic solution. The study found that the adsorption follows the Langmuir model, and the kinetics of adsorption follows the model of pseudosecond order
Resumo:
O processamento térmico de materiais cerâmicos via energia de microondas, no estágio atual, vem ganhando cada dia mais importância, tendo em vista suas inúmeras aplicações, como por exemplo: aplicação de microondas na área de processamento mineral (aquecimento de minérios antes da moagem, secagem, redução carbotérmica de óxidos minerais, lixiviação, fusão, pré-tratamento de minérios e concentrados de ouro refratário, regeneração de carvão, etc. de acordo com Kigman & Rowson, 1998). Em virtude de uma série de vantagens em potencial, frente aos métodos convencionais de aquecimento, como redução no tempo de processamento; economia de energia; diminuição do diâmetro médio das partículas e melhoramento nas propriedades tecnológicas em geral, esta tecnologia vem se destacando. Neste contexto, o objetivo geral deste trabalho, é desenvolver uma pesquisa visando identificar e caracterizar novas opções de matérias-primas cerâmicas como argilas, feldspatos e caulins que sejam eficazes para definir a formulação de uma ou mais massas para produção de componentes de cerâmica estrutural com propriedades físicas, mecânicas e estéticas adequadas após passarem por sinterização convencional e por energia de microondas destacando as vantagens desta última. Além dos requisitos técnicos e de processo, as formulações apresentadas deverão atender às expectativas de preço e de logística de fornecimento. No estudo foram conformados corpos-de-prova por extrusão e prensagem, sinterizados em fornos microondas e convencional, sob ciclos de queima mais rápidos que os atualmente praticados. As matérias-primas foram caracterizadas e analisadas, utilizando as técnicas de fluorescência por raios X (FRX), difração por raios X (DRX), análise térmica diferencial (DTA), análise térmica gravimétrica (DTG), análise granulométrica (AG), microscopia eletrônica de varredura (MEV), absorção d agua (AA), massa especifica aparente (MEA), porosidade aparente (PA), retração linear (RL) e tensão de ruptura e flexão (TRF). Os resultados obtidos indicaram que as propriedades tecnológicas de Absorção de água (AA) e Tensão de Ruptura e flexão (TRF), proposto no trabalho foram adquiridos com sucesso e estão bem além do limite exigido pelas especificações das normas da ABNT NBR 15.270/05 e 15.310/09
Resumo:
Objective- Convinced that periodontium, many times, can show alterations in human health, the aim of these studies was to investigate the periodontal situation in patients with endocrine-metabolic disorders such as, Berardinelli-Seip Syndrome, hyperthyroidism, hypothyroidism and acromegaly. Methods- Eight patients with Berardinelli-Seip Syndrome, 16 acromegalics, 30 hypothyroids, 30 hyperthyroids, and a control group with 35 patients were evaluated. Clinical attachment loss, probing depth, gingival bleeding index, gingival overgrowth and Index of Decayed, Missing and Filled Teeth were measured in each patient. All ethical aspects were rigidly observed, being the study conducted after its approval by the University of Fortaleza Research Ethics Committee. Results- The presence of periodontitis was marked in hyperthyroids and in patients with Berardinelli-Seip Syndrome. Hypothyroids showed not much presence of periodontitis, while all acromegalics presented absence of periodontitis. Conclusions- The protective effect of periodontitis in acromegalic patients is a new finding, whose mechanisms are not yet clear, but may be related to the anabolic effects of growth hormone. The presence of periodontitis in Berardinelli-Seip Syndrome may occur due the early onset of diabetes. In hyperthyroids, the high prevalence of periodontitis could be linked to thyroid hormones effects on bone, explaining also the minor prevalence in hypothyroids
Resumo:
The thesis has its largest array in the reorganization of science that is built from the middle of the last century and its horizon reconnection between scientific culture and humanistic culture, and the dialogue between science, art and literature. This epistemological regeneration view of the scientific paradigm incorporates the poetic language and sociological analysis, and brings out a complex, open and transdisciplinary narrative. To undertake this exercise as interlocutors we have thinkers like Nietzsche, Lévi-Strauss, Edgar Morin and Bruno Latour, to name a few, and as a reference for analyzing the entire artistic production of one of the icons of Brazilian music, Clara Nunes. It is problematized up in this work, through the singer s discography, lyrics and fragments of her biography, the construction of a social character that politicized culture, increased the mestizo consciousness of popular imagery, and exceeded the excessively prosaic narratives of the academic and scientific culture. The central argument of the thesis recognizes a Hybrid Subject Clara Nunes, as indeed is what is expected of the politically engaged intellectual in the 21st century