553 resultados para Appliances


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OBJECTIVE: To determine if changes in the lower intercanine widths during orthodontic treatment with fixed appliances result in gingival margin changes around the lower canines and incisors. METHOD: Pre- and post-treatment intra-oral photographs and orthodontic study models of 178 Caucasian adolescents (101 female, 77 male) were used. All subjects were treated with fixed appliances. The subjects had mean ages of 11.41 (SD: 1.83) years and 14.91 (SD: 1.78) years on their initial and final records respectively. The latter were taken 28 days or more after the appliances had been removed. The inclusion criteria were: Angle Class I or Class II malocclusion (with or without transverse and/or vertical discrepancies); nonextraction treatment; less than 4 mm crowding or spacing; fully erupted lower incisors and good periodontal health. The intercanine widths and the positions of the gingival margins relative to the maximum curvatures of the labial surfaces of the lower canines and incisors were measured with digital calipers. RESULTS: A significant association was found between unaltered intercanine widths and coronal migration of the gingival margins (p = 0.045). There were no significant associations between either increased or reduced intercanine widths and changes in the gingival margins. CONCLUSIONS: Following orthodontic treatment coronal migration of the gingival margins around the lower incisors and canines is more likely to be associated with an unaltered intercanine width.

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This study aimed to evaluate the effect of surface glazing and polishing of yttrium-stabilized tetragonal zirconia polycrystal ceramic on early dental biofilm formation, as well as the effect of brushing on the removal of adhered bacteria. Two subjects used oral appliances with polished and glazed samples fixed to the right and left sides. After 20 minutes, 1 hour, and 6 hours, the subjects manually brushed the samples on the right side. The samples were analyzed using scanning electron microscopy. Granular material was verified on the samples, especially on irregular surfaces. After 1 hour, there was no significant difference between glazed and polished surfaces in terms of bacterial presence. However, glazed surfaces tended to accumulate more biofilm, and brushing did not completely remove the biofilm. Polished surfaces seem to present a lower tendency for biofilm formation. Int J Prosthodont 2007;20:419-422.

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This in vivo experimental study evaluated the efficacy of fluoride-releasing elastomers in the control of Streptococcus mutans levels in the oral cavity. Forty orthodontic patients were recruited and divided into two groups of 20. Fluoride-releasing elastomeric ligature ties (Fluor-I-Ties, Ortho Arch Co. Inc., USA) were used in the experimental group, and conventional elastomeric ligature ties (D. Morelli, Brazil), in the control group. Two initial samples of saliva were collected at a 14-day interval to determine the number of colony forming units (CFU) of Streptococcus mutans. Immediately after collecting the second sample, fluoride-releasing elastomeric ligature ties were placed in the patients of the experimental group, and conventional ligature ties, in the patients of the control group. Seven, 14 and 28 days after placement of the elastomeric ligature ties, saliva and plaque surrounding the orthodontic appliance were collected for microbiologic analysis. There were no significant differences in the number of Streptococcus mutans CFUs in saliva or plaque in the area surrounding the fluoride-releasing or conventional elastomeric ligature ties. Thus, fluoride-releasing elastomeric ligature ties should not be indicated to reduce the incidence of enamel decalcification in orthodontic patients. Since there was no significant reduction in S. mutans in saliva or plaque, other means of prevention against enamel decalcification should be indicated for these patients.

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The objective of this study was to assess the salivary residual effect of fluoride dentifrice on human enamel subjected to an erosive challenge. This crossover in situ study was performed in two phases (A and B), involving ten volunteers. In each phase, they wore acrylic palatal appliances, each containing 3 human enamel blocks, during 7 days. The blocks were subjected to erosion by immersion of the appliances in a cola drink for 5 minutes, 4 times a day. Dentifrice was used to brush the volunteers' teeth, 4 times a day, during 1 minute, before the appliance was replaced into the mouth. In phases A and B the dentifrices used had the same formulation, except for the absence (PD) or presence (FD) of fluoride, respectively. Enamel alterations were determined using profilometry, microhardness (%SMHC), acid- and alkali-soluble F analysis. The data were tested using ANOVA (p < 0.05). The concentrations (mean ± SD) of alkali- and acid-soluble F (μgF/cm 2) were, respectively, PD: 1.27 a ± 0.70/2.24∧ A ± 0.36 and FD: 1.49 a ± 0.44/2.24∧ ± 0.67 (p > 0.05). The mean wear values (± SD, μm) were PD: 3.63 a ± 1.54 and FD: 3.54 a ± 0.90 (p > 0.05). The mean %SMHC values (± SD) were PD: 89.63 a ± 4.73 and FD: 87.28 a ± 4.01 (p > 0.05). Thus, we concluded that the residual fluoride from the fluoride-containing dentifrice did not protect enamel against erosion.

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Aim: The aim of this study was to evaluate in situ, the early bacterial colonization on feldspar-ceramics submitted to different glazing. Methods and Materials: Fourteen standardized disc specimens (diameter: 5 mm, thickness: 1.5 mm) of each of two micro-particulate feldspathic ceramics (VM7 and VM13, Vita) were produced according to manufacturers' specifications for a total of 28 specimens (24 for the analysis of biofilm and 4 for topographic analysis analyzing the ceramic surfaces). Specimens from each type of ceramic were submitted to two different glazing methods composing four groups: VM7 glazed using glazing liquid Vita Akzent® 25 (G1) and glaze firing (G2), VM13 glazed using glazing liquid (G3) and glaze firing (G4). Six individuals (n=6) wore oral appliances with four ceramic specimens, fixed on the buccal face of the appliances. After 8 hours, each sample was evaluated for the presence (1) or absence (0) of bacterial colonization under a scanning electron microscope (SEM) on five randomly selected fields. The value for each sample was cumulative of the results observed in the fields. One sample from each group was evaluated under a SEM to verify the topographic pattern. Results: There was no difference with regard to bacterial colonization between the feldspar-ceramics and between the glazing types (Kruskal-Wallis non-parametric test). Conclusion: Feldspar-ceramics submitted to firing or glaze firing with Vita Akzent® 25 present a similar condition for in situ bacterial colonization. The similar topographic pattern of the ceramic surfaces seems to have influenced the bacterial colonization.

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Introduction: The snoring is produced by the vibration of the soft palatum and/or other oropharyngeal tissues, during the air passage, in the breathing function. OSAHS is defined as the closing of 30%, at least, of the nasal/ buccal airway for 10 seconds or more, in spite of existing inspiratory effort, accompanied by oxyhemoglobin de- saturation of 4% or more. Objectives: To evaluate the available scientific evidence about the use of mandibular advancement intraoral appliances in the treatment of the snoring and/or OSAHS. Methodology: Electronic search strategy using predefined key-words and criteria was realized including studies published until October of 2008. It was also used the qualitative evaluation of the articles methodology. Results: Although a significant number of articles has studied this subject, only 7 articles showed methodological quality to be included in this systematic review. Conclusions: The intraoral appliances are widely prescribed for the treatment of snoring and OSAHS as primary therapy and as an alternative to patients who are unable to tolerate the positive airway pressure therapy.

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Esthetic orthodontic appliances continue to appeal to more patients, which results in objections to extraction spaces that remain for several months during orthodontic therapy. This has led orthodontists to design temporary pontics that fill extraction sites and that can be reduced as the spaces close. This report describes a simple, efficient, and expeditious technique for making such pontics. © 2010 Quintessence Publishing Co, Inc.

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Objeti vo: Avaliar os efeitos da expansão lenta na maxila e na mandíbula com o aparelho ortodônti co removível superior com torno de expansão simétrico e mediano, nas regiões oclusal, gengival e alveolar de pacientes jovens com atresia maxilar. Método: A amostra compreendeu 18 indivíduos leucodermas (11 meninas e 7 meninos; idade média: 8 anos e 10 meses no início do tratamento) que apresentavam atresia da maxila, acompanhadas ou não de mordida cruzada posterior uni ou bilateral na fase de denti ção mista. Todos os pacientes foram tratados com aparelho ortodônti co removível superior com torno de expansão simétrico e mediano, sendo o tempo médio de tratamento de 15,4 meses (± 7,6). Para avaliar a infl uência do tratamento nas mensurações dos pontos demarcados nas regiões oclusal, gengival e alveolar, foram uti lizados os modelos de gesso dos arcos superior e inferior (36 pares) obti dos em dois tempos: T1: início do tratamento e T2: ao fi nal do tratamento. Para cada paciente em ambos os tempos, foram mensuradas as distâncias transversas na região oclusal entre caninos decíduos, 1o molares decíduos ou 1o pré-molares permanentes e entre 1o molares permanentes, superiores e inferiores. Para verifi car se a movimentação ocorreu por inclinação ou por movimento de corpo, foram uti lizadas também medidas nas regiões gengival e alveolar. Os dados foram avaliados estati sti camente pelo teste “t student para amostras pareadas (5%). Resultados: Observou-se que em T2, todas as distâncias mensuradas para as regiões oclusal, gengival e alveolar apresentaram valores estati sti camente superiores às mesmas medidas em T1 (p<0,05). Conclusão: O aparelho ortodônti co removível superior é efeti vo nos casos de expansão lenta da maxila, agindo também indiretamente nas dimensões transversas do arco inferior.

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This classical way to manage product development processes for massive production seems to be changing: high pressure for cost reduction, higher quality standards, markets reaching for innovation lead to the necessity of new tools for development control. Into this, and learning from the automotive and aerospace industries factories from other segments are starting to understand and apply manufacturing and assembly oriented projects to ease the task of generate goods and from this obtain at least a part of the expected results. This paper is intended to demonstrate the applicability of the concepts of Concurrent Engineering and DFM/DFA (Design for Manufacturing and Assembly) in the development of products and parts for the White Goods industry in Brazil (major appliances as refrigerators, cookers and washing machines), showing one case concerning the development and releasing of a component. Finally is demonstrated in a short term how was reached a solution that could provide cost savings and reduction on the time to delivery using those techniques.

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Aim: To evaluate the influence of construction bite in the dentoskeletal changes induced by Klammt Appliance. Methods: The sample consisted of 17 children, with Class II malocclusion and initial mean age of 8.5 years. The construction bite was obtained using an Exactobite on edge-toedge anteroposterior relationship with 3 mm interincisal clearance. The height of the acrylic was determined by initial overbite associated to interincisal clearance and measured with digital caliper. The amount of advancement was obtained and measured by initial overjet in the lateral radiography. Pearson's correlation, linear regression and ANOVA were used to determine the relationship between dentoskeletal and construction bite variables. Results: The increase in the height of the acrylic promotes a greater inhibition of the forward displacement of the nasal spine and reduction in the facial growth index. The increase in the mandibular advancement induces more downward displacement of nasal spine and pogonion; a counter-clockwise rotation of palatine plane; an increase in mandibular length, maxillary alveolar height and interincisal angle; a decrease in mandibular alveolar height, the intermaxillary discrepancy and overjet; and palatal tipping of upper incisors. Conclusions: The different dimensions of the construction bite influence the dentoskeletal changes induced by the appliance in Class II treatment.

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Objective: The purpose of this study was to evaluate the facial profile changes induced by Balters' bionator appliance in Class II division 1 patients, at mixed dentition stage. Methods: The sample consisted of 28 prepubertal individuals at stages 1 and 2 of skeletal maturation (CVM), which were divided in two groups. The experimental group consisted of 14 individuals (7 boys and 7 girls, initial mean age of 8y12m) which were treated with Balters' bionator appliance for 14.7 months. The effects of treatment were compared to a control group of 14 subjects (7 boys and 7 girls, initial mean age of 8y5m) with Class II malocclusion, division 1, not orthodontically treated, which were followed up for 15.4 months. The statistical analysis was performed using Student's t test, at a significance level of 5%. Results: The results showed that the Balters' bionator appliance promoted a significant increase on the mentolabial angle, in addition to demonstrating a tendency to reduce the facial skeletal convexity, to restrict the maxillary growth and to increase the nasolabial angle and the lower anterior facial height. Conclusion: It can be concluded that the Balters' bionator appliance improved the facial profile of children treated at mixed dentition stage. © 2013 Dental Press Journal of Orthodontics.

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Pós-graduação em Ciência dos Materiais - FEIS

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)