147 resultados para MHC class I


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We report a novel nonclassical class I HLA-E*01:06 allele observed in Brazilian individuals.

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Adhesive restorations have increasingly been used in dentistry, and the adhesive system application technique may determine the success of the restorative procedure. The aim of this study was to evaluate the influence of the application technique of two adhesive systems (Clearfil SE Bond and Adper Scotchbond MultiPurpose) on the bond strength and adhesive layer of composite resin restorations. Eight human third molars were selected and prepared with Class I occlusal cavities. The teeth were restored with composite using various application techniques for both adhesives, according to the following groups (n = 10): group 1 (control), systems were applied and adhesive was immediately light activated for 20 seconds without removing excesses; group 2, excess adhesive was removed with a gentle jet of air for 5 seconds; group 3, excess was removed with a dry microbrush-type device; and group 4, a gentle jet of air was applied after the microbrush and then light activation was performed. After this, the teeth were submitted to microtensile testing. For the two systems tested, no statistical differences were observed between groups 1 and 2. Groups 3 and 4 presented higher bond strength values compared with the other studied groups, allowing the conclusion that excess adhesive removal with a dry micro-brush could improve bond strength in composite restorations. Predominance of adhesive fracture and thicker adhesive layer were observed via scanning electron microscopy (SEM) in groups 1 and 2. For groups 3 and 4, a mixed failure pattern and thinner adhesive layer were verified. Clinicians should be aware that excess adhesive may negatively affect bond strength, whereas a thin, uniform adhesive layer appears to be favorable. (Quintessence Int 2013;44:9-15)

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This research presents the results of a cephalometric radiography study, in frontal norm, that was used to measure the possible linear correlations between several linear dimensions of the face, in a sample of a 140 caucasian brazilians, with an average age of 20 years, who were distributed in 2 groups as follows: Control group - formed of 35 males and 35 females, with no apparent facial deformities and with dental oclusion, not necessarily, in Angle's Class I; Unilateral cleft lip and palate group - formed of 35 males and 35 females with surgical correction of the up in the first year and of the palate until the third year of life, without orthodontic treatment. ln each teleradiography, the following parameters were measured using a computer: - Lateral orbit width or external orbit width (LOe) - Medial orbit width or internal orbit width (LOI) - Zygomatic width or facial width (LZI) - Mastold width (LMa) - Maxilar width (LMx) - Nasal width (LNa) - Condilar width (LCo) - Antigonial width (LGa) The values obtained were treated statistically using quantitative analysis (arithmetic mean, standard deviation, standard mean error, Person's variation factor and Pearson factor linear correlation). Theirs significance was established by Student's t test. The Pearson factor linear correlations determined between transverse linear cephalometric width dimensions of face in frontal norm for individuals of both groups and sex, with an average age of 20 years, were: ...

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O objetivo do presente estudo foi investigar a influência da pressão intrapulpar e da profundidade dentinária sobre o desempenho adesivo de dois agentes de união à dentina, Single Bond (3M ESPE, St. Paul, MN, EUA) e Clearfil SE Bond (Kuraray, Tokyo, Japão), aplicados in vitro e in vivo. Quarenta e oito prémolares superiores hígidos foram selecionados e os pares pertencentes aos mesmos pacientes foram aleatoriamente distribuídos em 4 grupos experimentais de acordo com o sistema adesivo e a pressão intrapulpar, presente ou ausente. Dos dentes pertencentes ao mesmo par, um foi tratado in vivo e o outro in vitro. A ausência ou presença de pressão intra-pulpar foi determinada in vivo pelo uso de anestésicos locais com ou sem vasoconstritor, respectivamente. In vitro, os dentes foram mantidos sob pressão hidrostática de 15 cm de água por 24 horas. Cavidades de classe I foram preparadas e os sistemas adesivos aplicados de acordo com a recomendação dos fabricantes, seguidos da restauração incremental em resina composta. Para os dentes tratados in vitro, os mesmos procedimentos restauradores foram realizados após 6 meses de armazenagem em solução contendo timol 0,1%. Espécimes com área de secção transversal de 1 mm2 foram obtidos e submetidos ao ensaio mecânico de microtração. In vivo, ambos os sistemas adesivos apresentaram desempenho adesivo comparável, enquanto in vitro, o sistema Single Bond foi superior ao sistema Clearfil SE Bond. Esse último não foi influenciado por nenhuma das variáveis estabelecidas no estudo, ou seja, aplicação in vitro ou in vitro, presença de pressão intrapulpar e profundidade em dentina. O sistema Single Bond aplicado sob pressão intrapulpar positiva sofreu variação significante de resistência de união em função da profundidade da dentina, ou seja, em dentina profunda seu desempenho adesivo... (Resumo completo, clicar acesso eletrônico abaixo)

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This case report describes the interdisciplinary treatment of a 19-year-old Brazilian man with a Class I malocclusion, a hyperdivergent profile, an anterior open bite, and signs of temporomandibular joint internal derangement. The treatment plan included evaluation with a temporomandibular joint specialist and a rheumatologist, orthodontic appliances, and maxillomandibular surgical advancement with counterclockwise rotation. Cone-beam computed tomography images were taken before and after surgery at different times and superimposed at the cranial base to assess the changes after orthognathic surgery and to monitor quantitatively the internal derangement of the temporomandibular joints and surgical relapse. Our protocol can improve the orthodontist's understanding of surgical instability, demonstrate the clinical value of cone-beam computed tomography analysis beyond the multiplanar reconstruction, and guide patient management for the best outcome possible.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Objective: To evaluate the velocity of canine retraction, anchorage loss and changes on canine and first molar inclinations using self-ligating and conventional brackets.Materials and Methods: Twenty-five adults with Class I malocclusion and a treatment plan involving extractions of four first premolars were selected for this randomized split-mouth control trial. Patients had either conventional or self-ligating brackets bonded to maxillary canines randomly. Retraction was accomplished using 100-g nickel-titanium closed coil springs, which were reactivated every 4 weeks. Oblique radiographs were taken before and after canine retraction was completed, and the cephalograms were superimposed on stable structures of the maxilla. Cephalometric points were digitized twice by a blinded operator for error control, and the following landmarks were collected: canine cusp and apex horizontal changes, molar cusp and apex horizontal changes, and angulation changes in canines and molars. The blinded data, which were normally distributed, were analyzed through paired t-tests for group differences.Results: No differences were found between the two groups for all variables tested.Conclusions: Both brackets showed the same velocity of canine retraction and loss of anteroposterior anchorage of the molars. No changes were found between brackets regarding the inclination of canines and first molars.

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During the orthodontic correction planning in addition to dental-jaw correction, facial aesthetics is the orthodontist's and patient's major concern. To prevent facial aesthetics damage is really important to take into account the type of craniofacial growth: mesofacial (balanced), dolichofacial (vertical) or brachyfacial (horizontal). We evaluated 152 documentation files from the Department of Orthodontics of Dental University of Sao Jose dos Campos- UNESP in order to analyze what kind of growth occurs in most Class I malocclusions, Class II and Class III Angle of treated individuals from 6 to 12 years old. From the randomly collected samples, 15 of them belonged to Class I Angle malocclusions; 123 belonged to Angle Class II and 14 to Class III malocclusion. The results showed that in Class I, 66.67% were classified as dolicocephalic; in Class II, 64.23% were classified as dolicocephalic and in Class III, 50% were brachycephalic. We conclude that the dolichofacial was the type which ocurred the most, both in females and males and both in malocclusion Class I and Class II. The brachyfacial type most occurred in Class III malocclusion and the mesofacial type occurred in smaller numbers in the three malocclusions studied

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We evaluated the frequency of different HLA-DRB1 alleles in Plasmodium vivax-infected individuals and in healthy blood donors from malaria endemic areas of Brazil. Low-resolution human leukocyte antigen-DRB1 genotyping was performed for 73 malaria patients and 29 healthy blood donors. The most frequent alleles in individuals from northern Brazil were human leukocyte antigen-DRB1*04, *08, *07 and *13. The frequency of human leukocyte antigen-DRB1*07 was higher in malaria-infected individuals than in the control group, which reinforces the theory that this allele plays an important role in susceptibility to malaria. This study offers new information about a potential susceptibility factor for P. vivax malaria in a Brazilian population that is naturally exposed to malaria.