906 resultados para Orthodontic extrusion
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OBJECTIVE: To determine the prevalence of mesiodens in deciduous and mixed dentitions and its association with other dental anomalies. MATERIAL AND METHODS: Panoramic radiographs of 1,995 orthodontic patients were analyzed retrospectively, obtaining a final sample of 30 patients with mesiodens. The following aspects were analyzed: gender ; number of mesiodens; proportion between erupted and non-erupted mesiodens; initial position of the supernumerary tooth; related complications; treatment plan accomplished; and associated dental anomalies. The frequency of dental anomalies in the sample was compared to reference values for the general population using the chi-square test (c²), with a significance level set at 5%. RESULTS: The prevalence of mesiodens was 1.5% more common among males (1.5:1). Most of the mesiodens were non-erupted (75%) and in a vertical position, facing the oral cavity. Extraction of the mesiodens was the most common treatment. The main complications associated with mesiodens were: delayed eruption of permanent incisors (34.28%) and midline diastema (28.57%). From all the dental anomalies analyzed, only the prevalence of maxillary lateral incisor agenesis was higher in comparison to the general population. CONCLUSION: There was a low prevalence of mesiodens (1.5%) in deciduous and mixed dentition and the condition was not associated with other dental anomalies, except for the maxillary lateral incisor agenesis.
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OBJECTIVE: The aim of this study was to compare by means of McNamara as well as Legan and Burstone's cephalometric analyses, both manual and digitized (by Dentofacial Planner Plus and Dolphin Image software) prediction tracings to post-surgical results. METHODS: Pre and post-surgical teleradiographs (6 months) of 25 long face patients subjected to combined orthognathic surgery were selected. Manual and computerized prediction tracings of each patient were performed and cephalometrically compared to post-surgical outcomes. This protocol was repeated in order to evaluate the method error and statistical evaluation was conducted by means of analysis of variance and Tukey's test. RESULTS: A higher frequency of cephalometric variables, which were not statistically different from the actual post-surgical results for the manual method, was observed. It was followed by DFPlus and Dolphin software; in which similar cephalometric values for most variables were observed. CONCLUSION: It was concluded that the manual method seemed more reliable, although the predictability of the evaluated methods (computerized and manual) proved to be reasonably satisfactory and similar.
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Adhesion and colonization of the oral cavity by Candida albicans is an initial step in candidosis. Orthodontic and other oral appliances seem to favor candidal presence. The aim of this work was to compare the presence of Candida species in saliva, their adherence to oral epithelial cells, and the levels of anti-C. albicans IgA in children with or without orthodontic appliances. This study included 30 children 5 to 12 years old (9.1 ± 1.7 years old) who were users of removable orthodontic devices for at least 6 months and 30 control children of similar ages (7.7 ± 1.5 years old). The presence of yeast species in the saliva was evaluated by microbiological methods. Candida species were identified using phenotypic methods. Anti-C. albicans IgA levels in saliva were analyzed by ELISA. The yeasts adhering to oral epithelial cells were assessed by exfoliative cytology. No statistically significant differences were observed for saliva yeast counts and anti-C. albicans IgA levels between the studied groups. Children with orthodontic devices exhibited more yeast cells adhering to oral epithelial cells and a higher percentage of non-albicans species relative to the control group. In conclusion, orthodontic appliances may favor the adherence of Candida to epithelial cells but do not influence the presence of these yeasts in saliva, and the levels of anti-C. albicans IgA do not correlate with yeast adherence or presence of Candida in the oral cavity
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Introduction: The aim of this study was to assess the influence of curing time and power on the degree of conversion and surface microhardness of 3 orthodontic composites. Methods: One hundred eighty discs, 6 mm in diameter, were divided into 3 groups of 60 samples according to the composite used-Transbond XT (3M Unitek, Monrovia, Calif), Opal Bond MV (Ultradent, South Jordan, Utah), and Transbond Plus Color Change (3M Unitek)-and each group was further divided into 3 subgroups (n = 20). Five samples were used to measure conversion, and 15 were used to measure microhardness. A light-emitting diode curing unit with multiwavelength emission of broad light was used for curing at 3 power levels (530, 760, and 1520 mW) and 3 times (8.5, 6, and 3 seconds), always totaling 4.56 joules. Five specimens from each subgroup were ground and mixed with potassium bromide to produce 8-mm tablets to be compared with 5 others made similarly with the respective noncured composite. These were placed into a spectrometer, and software was used for analysis. A microhardness tester was used to take Knoop hardness (KHN) measurements in 15 discs of each subgroup. The data were analyzed with 2 analysis of variance tests at 2 levels. Results: Differences were found in the conversion degree of the composites cured at different times and powers (P < 0.01). The composites showed similar degrees of conversion when light cured at 8.5 seconds (80.7%) and 6 seconds (79.0%), but not at 3 seconds (75.0%). The conversion degrees of the composites were different, with group 3 (87.2%) higher than group 2 (83.5%), which was higher than group 1 (64.0%). Differences in microhardness were also found (P < 0.01), with lower microhardness at 8.5 seconds (35.2 KHN), but no difference was observed between 6 seconds (41.6 KHN) and 3 seconds (42.8 KHN). Group 3 had the highest surface microhardness (35.9 KHN) compared with group 2 (33.7 KHN) and group 1 (30.0 KHN). Conclusions: Curing time can be reduced up to 6 seconds by increasing the power, with a slight decrease in the degree of conversion at 3 seconds; the decrease has a positive effect on the surface microhardness.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Orthodontic therapy is known to be associated with the development of gingival recession. Several factors may be involved in the causal chain of this outcome, including anatomical and behavioral aspects. Among the anatomical aspects, the dimensions of the mandibular symphysis could play a predisposing role. This study evaluated the relationship between the mandibular symphysis dimensions prior to orthodontic therapy and the development of gingival recessions on the lower incisors and cuspids. Records from 189 orthodontically treated adolescents were evaluated, including radiographs, casts and intra-oral photographs. Symphysis dimensions were assessed by cephalograms. Gingival margin alterations were determined in photographs and cast models. Association between gingival margin alterations and symphysis dimensions was tested by chi-square (α=0.05). Occurrence of gingival recession increased after orthodontic therapy. No association was observed on average of symphysis dimensions and the occurrence of gingival recessions. It may be concluded that pretreatment symphysis dimensions may not be used as predictors of gingival recession after orthodontic therapy.
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The synthetic intermaxillary elastic emerged as an alternative for clinical use in patients with latex sensitivity. However, there are disagreements about this elastic protocol use according to the force degradation. The aim of this study was to evaluate, in vitro, the forces generated by latex and synthetic elastics over time. Material and methods: Sample size of 840 elastics were used (420 latex and 420 synthetic), delivering medium strength (Dental Morelli®) with internal diameter of 1/8", 3/16", 1/4" and 5/16". The elastics were randomly divided into 7 groups according to the time of the force measuring and immersed into distilled water at 37°C. To measure the force in each group, the elastics were stretched in six progressive increases of 100% of its internal diameter with the aid of a testing machine Emic and measured up to 72 hours. Data were analyzed with SPSS 16.0, using one-way analysis of variance (ANOVA). Results: Immediate force level of synthetic elastics was statistically higher than latex elastics in all strains, for the same size. However, the latex elastics mean forceslightly decreased over time, while the synthetic elastics presented an abrupt decrease. Conclusion: In view of these findings, Sudanese homemade alcoholic beverages cause oral epithelial atypical changes, which lead to oral precancerous and cancerous lesions. OEFC is a useful procedure for detection and assessment of oral ET.
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Introduction and Objective: The synthetic intermaxillary elastic emerged as an alternative for clinical use in patients with latex sensitivity. However, there are disagreements about this elastic protocol use according to the force degradation. The aim of this study was to evaluate, in vitro, the forces generated by latex and synthetic elastics over time. Material and methods: Sample size of 840 elastics were used (420 latex and 420 synthetic), delivering medium strength (Dental Morelli®) with internal diameter of 1/8”, 3/16”, 1/4” and 5/16”. The elastics were randomly divided into 7 groups according to the time of the force measuring and immersed into distilled water at 37°C. To measure the force in each group, the elastics were stretched in six progressive increases of 100% of its internal diameter with the aid of a testing machine Emic and measured up to 72 hours. Data were analyzed with SPSS 16.0, using one-way analysis of variance (ANOVA). Results: Immediate force level of synthetic elastics was statistically higher than latex elastics in all strains, for the same size. However, the latex elastics mean force slightly decreased over time, while the synthetic elastics presented an abrupt decrease. Conclusion: The synthetic elastic presented severe force degradation, jeopardizing the cost-benefit ratio, which indicates a higher replacement frequency. The latex elastic showed better mechanical performance in comparison to synthetic ones.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Extensive intraosseous lesions represent a clinical challenge for the periodontist. Sites with bone defects have been shown to be at higher risk of periodontitis progression in patients who had not received periodontal therapy. Thus, the aim of this case report was to describe a novel approach for the treatment of 1-walled intraosseous defect by combining nonsurgical periodontal therapy and orthodontic movement toward the bone defect, avoiding regenerative and surgical procedures. A 47-year-old woman underwent the proposed procedures for the treatment of her left central incisor with 9 mm probing depth and 1-walled intraosseous defect in its mesial aspect. Initially, basic periodontal therapy with scaling and root planning was accomplished. Two months later, an orthodontic treatment was planned to eliminate the intraosseous lesion and to improve the interproximal papillary area. Orthodontic root movement toward the osseous defect was performed for 13 months with light forces. After 6 years postoperative it was concluded that combined basic periodontal therapy and orthodontic movement was capable of eliminating the intraosseous defect and improve the esthetics in the interproximal papillary area between the central incisors.
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The removal of resin debris and/or resin cement from the enamel surface without causing iatrogenic is the main objective when removing the orthodontic brackets. Some factors such as the time required for removal, damage to the tooth structure, are essential factors for the clinician at the time of removal. Various techniques are used for the removal of orthodontic brackets after the treatment; it is known that the use of clinical procedures such as the use of diamond burs and some pliers removers can damage the structure of the enamel, often depending on the bond strength that should be taken into consideration at the time of removal. This literature review aims to gather the most relevant studies that can clarify the clinical technique, which may be more suitable for removal of the brackets.
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Aim: The purpose of this study was to assess chlorhexidine effects on plaque index and salivary levels of mutans streptococci (MS) when used as the immersion solution for removable orthodontic appliances and added to their acrylic resin composition. Methods: Forty-five patients (6 to 12 years old) were randomly assigned into three groups with 15 patients each. Group I (control)—without orthodontic appliances disinfection; Group II—removable orthodontic appliances which had been immersed in 0.12% chlorhexidine digluconate overnight (8 hours), and Group III—orthodontic appliances in which 0.12% chlorhexidine digluconate solution had been incorporated into their resin composition. Saliva was collected for quantification of MS and evaluation of plaque index was performed before and after installation of orthodontic appliance at 0, 2, 4, 6, 8, and 10 weeks. Data were analyzed by using analysis of variance. Results: Number of MS colonies in saliva and plaque index showed no statistically differences among groups at the different periods (p > 0.05). Conclusions: It could be concluded that chlorhexidine incorporation into the acrylic resin of removable orthodontic appliances at 0.12% concentration and immersion of the appliance into 0.12% chlorhexidine solution were not effective in reducing plaque index and the number of MS in saliva.