409 resultados para Autogenous grinding
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Objectives: the aim of this work was to define the range of possible values for each isotope of carbon-13 and nitrogen-15 for cocaine and marijuana seized in Botucatu-SP, with the intention of distinguishing the geographical origin of the drug. Materials and Methods: samples of marijuana and cocaine were collected at the time of incineration. Then, at the Stable Isotope Center from São Paulo State University in Botucatu, São Paulo, Brazil, samples of marijuana were subjected to the drying process and subsequent grinding. Samples of cocaine were not submitted to the processes of drying and grinding because they were already in adequate granulometry. Subsequently, the samples of both drugs were weighed in accordance with the standards for carbon-13 and nitrogen-15. Lastly, CO2 and N2 gases were obtained from the samples through the elemental analyzer. They were then analyzed in a mass spectrometer to obtain values of δ13C and δ15N in ‰. Results and Discussion: the results of marijuana allowed for comparison with regions of Queensland, Australia, according to the range of δ13C between -29.9 ‰ and -29.3 ‰ and δ15N range from 4.1 ‰ to 5.8 ‰. The results were also consistent with those of the state of Pará, Brazil, where the values of δ13C and δ15N were -30.3 ± 0.7 ‰ and 5.0 ± 1.3 ‰, respectively. Also the results were in accordance with those from the state of Mato Grosso do Sul, Brazil, in which δ13C values varied by -28.7 ± 1.3 ‰, and δ15N values varied by 6.6 ± 1.1 ‰, respectively. In both regions, the samples identified as being from Pará and Mato Grosso do Sul showed an overlap. In addition, the results fitted with data from the state of Maranhão, in which the values of δ13C and δ15 N were -28.8 ± 1.6 ‰ and 2.9 ± 2.5 ‰, respectively. In the case of cocaine, the present study could not be related to the results from the literature. One possible explanation may be related to the non-purification of ...
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Pós-graduação em Engenharia Civil - FEIS
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The early tooth loss and periodontal disease often leave inadequate bone volume for installation of osseointegrated implants. The autogenous bone graft is considered the gold standard for reconstruction of residual bone defects. Some surgical techniques can be performed, including extra or intraoral donor sites depending on the degree of bone loss, depending on surgical-prosthetic planning and general condition of the patient. The intraoral bone grafts offer a safe option to rebuilt bone volume in smaller rehabilitations, with low morbidity and minimal postoperative discomfort. Among the possible donor sites, the mandibular ramus and body, which offer predominantly cortical bone, and the chin area, which offers corticomedullary bone tissue, can be harvested. The graft will be suitable both in quantity and quality, preserving the capacity of osteogenesis, osteoinduction and osteoconduction, which differentiate autogenous grafts from other biomaterials. The aim of this study was to report a clinical case in which the mandibular ramus graft was used for total reconstruction of an edentulous maxilla, showing that even large areas can be reconstructed with grafts from intraoral origin. All the steps that allowed the complete reconstruction of the maxilla done by an intraoral donor area are listed in the text, culminating in an extremely satisfactory clinical result.
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The bone resorption in the anterior maxilla, due to its aesthetic importance, can be considered one of the challenges in implant dentistry. Autogenous bone graft is the most indicated bone augmentation procedure, aiming an implant supported rehabilitation.. Alternatively, some other graft procedures can be done with homogenous and xenogenous bone graft, biomaterials and different associations. Additionally to the mentioned biomaterials, the bone morphogenetic protein (BMP), specially the rhBMP-2, which was characterized as a bone osteoinductor, and consecutively, a potential autogenous graft substitute, with previsibility and no necessity of association to other biomaterial. The objective of this study is to present a single case using the rhBMP-2 for bone augmentation.
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Purpose: The aim of this systematic review was to evaluate clinical and safety data for recombinant human bone morpho-genetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier when used for alveolar ridge/maxillary sinusaugmentation in humans.Materials and Methods: Clinical studies/case ser ies published 1980 through June 2012 using rhBMP-2/ACS were searched.Studies meeting the following criteria were considered eligible for inclusion: >10 subjects at baseline and maxillary sinus oralveolar ridge augmentation not concomitant with implant placement.Results: Seven of 69 publications were eligible for review. rhBMP-2/ACS yielded clinically meaningful bone formationfor maxillary sinus augmentation that would allow placement of regular dental implants without consistent differencesbetween rhBMP-2 concentrations. Never theless, the statistical analysis showed that sinus augmentation following autog-enous bone graft was significantly greater (mean bone height: 1.6 mm, 95% CI: 0.5–2.7 mm) than for rhBMP-2/ACS(rhBMP-2 at 1.5 mg/mL). In extraction sockets, rhBMP-2/ACS maintained alveolar ridge height while enhancing alve olarridge width. Safety reports did not represent concerns for the proposed indications.Conclusions: rhBMP-2/ACS appears a promising alternative to autogenous bone grafts for alveolar ridge/maxillary sinusaugmentation; dose and carrier optimization may expand its efficacy, use, and clinical application.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This study evaluated postoperative results of 8 cases of frontal sinus fractures treated by frontal sinus obliteration with autogenous bone from the anterior iliac crest. Patients and methods: The medical charts of patients sequentially treated for frontal sinus fractures by obliteration with autogenous cancellous iliac crest bone in the Oral and Maxillofacial Surgery Division of this institution were reviewed. From those, eight had complete records and adequately described long-term follow-up. All were operated by the same surgical team. Those patients were recalled and independently evaluated by 2 examiners. Radiographs and/or CT scans were available for this evaluation. Associated fractures and complications were noted. The average postoperative follow-up was 7 years, ranging from 3 to 16 years. The main complication was infection. Four patients (50%) had uneventful long-term follow-ups and four (50%) experienced complications requiring reoperation. Based on the studied sample studied the authors conclude that the obliteration with autogenous bone presented a high percentage of complications in this series.
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The correction of bone defects is the restoration of lost structures which can be replaced by alloplastic implants or bone grafts. Due to the known disadvantages of removal of autogenous grafts, most researches in dentistry aim to develop alloplastic or non-alloplastic materials able to replace bone without these limitations. Beta-Tricalcium Phosphate (β-TCP) is a synthetic granular bone substitute, biocompatible, osteoconductive, which can be used in the alveolar reconstruction. In this work, we perform a literature review on the β-TCP characteristics and discuss its application in dentistry.
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This study evaluated postoperative results of 8 cases of frontal sinus fractures treated by frontal sinus obliteration with autogenous bone from the anterior iliac crest.
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Objective The objective of this article is to present options of rehabilitation with dental implants in two cases of severely atrophic mandibles (<10 mm) after rigid internal fixation of fractures. Patients and method Two patients who sustained fractures in severely atrophic mandibles with less than 10 mm of bone height were treated by open reduction and internal fixation through a transcervical access. Internal fixation was obtained with 2.4-mm locking reconstruction plates. The first patient presented satisfactory bone height at the area between the mental foramens and after 2 years, received flapless guided implants in the anterior mandible and an immediate protocol prosthesis. The second patient received a tent pole iliac crest autogenous graft after 2 years of fracture treatment and immediate implants. After 5 months, a protocol prosthesis was installed in the second patient. Results In both cases, the internal fixation followed AO principles for load-bearing osteosynthesis. Both prosthetic devices were Branemark protocol prosthesis. The mandibular reconstruction plates were not removed. Both patients are rehabilitated without complications and satisfied with esthetic and functional results. Conclusion With the current techniques of internal fixation, grafting, and guided implants, the treatment of atrophic mandible fractures can achieve very good results, which were previously not possible.
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Bone defects at interdental osteotomy sites are as a complication of surgi-cally assisted rapid palatal expansion (SARPE). The replacement of osseoustissue by fibrous connective tissue impairs the spontaneous closure of adiastema between central incisors, and orthodontic tooth movementthrough the defect area may lead to root resorption. Treatment of such asituation requires an orthodontic-surgical approach. In this report, wedescribe the lack of bone healing at the midline osteotomy site after SARPE,which was treated by autogenous bone grafting as assessed by cone beamcomputed tomography. In addition, we discuss factors related to the aetiol-ogy and treatment of a bone defect after SARPE.
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Destruction of bone and periodontal ligament as a result of periodontal disease can lead to anatomical defects in the furcation area. Treatment of these lesions is a major challenge to the clinician. Periodontal instruments have limited access to this area and plaque and calculus removal from root surfaces are extremely difficult. For proper treatment planning a number of factors must be taken into consideration to achieve immediate and long term success. Surgical therapy associated with bone grafts may be a viable option in the treatment of class II furcation defects, aiming to restore lost tissues. The aim of this paper is to report a clinical case where a simplified surgical approach with the use of autogenous graft was used to treat a class II furcation defect Twelve months after the surgery, an increase in clinical attachment level and pocket depth reduction resulted in a complete closure of the furcation lesion.
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Introduction: The study of graft donor sites, whether from the anatomical, physiological or morphological point of view, has become a topic of current interest, due to the increasing number of patients needing facial bone reconstruction for various reasons. Purpose: In view of the need to constantly improve surgical techniques for autogenous bone graft harvesting, still considered the best choice for facial bone reconstruction, this paper describes an anatomical study on dry skulls in order to evaluate the average thickness of the parietal bone. Material and Methods: Measurements of this bone were taken with a goniometer, at four previously defined points, in the region that is often used as a donor site, in 49 dry skulls (98 parietal bones). The results were evaluated using the T test. Results: Thickness was measured at four predetermined points. The mean values (Point A = 4898mm, B = 4517mm, C = 6185mm, D = 4280mm) show that the bone can be even thinner than previously reported in the literature in other studies of the same nature. The largest bone thickness is in the medial and posterior region. Conclusion: A knowledge of these anatomical characteristics is helpful in preventing possible surgical complications, as well as making it safer for the surgeon to remove this graft and providing more information on whether or not to indicate this region as a bone graft donor site.