992 resultados para corrective orthodontics


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Patients with agenesis of maxillary lateral incisor must have in your planning functional and aesthetic considerations, important to the success of the treatment, regardless of whether the choice of treatment is closing or opening and maintenance of space for rehabilitation with prosthesis. This choice will depend on factors such as skeletal and tooth structure and profile. Children and adolescents are the group of individuals most exposed to trauma and fracture of the maxillary lateral incisor due to the activities they perform. Proper diagnosis and good treatment are essential to the success of the treatment. This article aims to report a case of agenesis of the maxillary lateral incisor along with the involvement of a root fracture of the maxillary central incisor. The orthodontic treatment was successfully finished with a favorable prognosis for the fractured incisor to stay in a esthetic and functional position.

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OBJECTIVE: The aim of this study was to assess the time spent for direct (DBB - direct bracket bonding) and indirect (IBB - indirect bracket bonding) bracket bonding techniques. The time length of laboratorial (IBB) and clinical steps (DBB and IBB) as well as the prevalence of loose bracket after a 24-week follow-up were evaluated. METHODS: Seventeen patients (7 men and 10 women) with a mean age of 21 years, requiring orthodontic treatment were selected for this study. A total of 304 brackets were used (151 DBB and 153 IBB). The same bracket type and bonding material were used in both groups. Data were submitted to statistical analysis by Wilcoxon non-parametric test at 5% level of significance. RESULTS: Considering the total time length, the IBB technique was more time-consuming than the DBB (p < 0.001). However, considering only the clinical phase, the IBB took less time than the DBB (p < 0.001). There was no significant difference (p = 0.910) for the time spent during laboratorial positioning of the brackets and clinical session for IBB in comparison to the clinical procedure for DBB. Additionally, no difference was found as for the prevalence of loose bracket between both groups. CONCLUSION: the IBB can be suggested as a valid clinical procedure since the clinical session was faster and the total time spent for laboratorial positioning of the brackets and clinical procedure was similar to that of DBB. In addition, both approaches resulted in similar frequency of loose bracket.

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The purpose of this study was to compare the effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors during leveling phase. Twenty-three subjects with Class I and Class II malocclusion were treated with first premolars extraction using preadjusted appliances (MBT 0.022-inch brackets). The leveling phase was performed with stainless steel archwires only. The sample was divided into 2 groups: 14 subjects received active lacebacks (Group 1) and 9 subjects received passive lacebacks (Group 2). Lacebacks were made from 0.008-inch ligature wire. Lateral cephalometric radiographs were taken pre- and post-leveling phase. Student's t-test was applied to determine the differences between pre- and post-leveling mean values and to determine the mean differences between groups. In Group I, the first molars showed a significant mesial movement, whereas no change was observed in Group 2. In both groups, maxillary central incisor crowns moved to lingual side. In conclusion, active laceback produced anchorage loss of maxillary first molars whereas passive laceback did not affect the position of these teeth. Active and passive lacebacks were effective in preventing central incisor proclination.

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OBJECTIVE: To describe and compare three alternative methods for controlling classical friction: Self-ligating brackets (SLB), special brackets (SB) and special elastomeric ligatures (SEB). METHODS: The study compared Damon MX, Smart Clip, In-Ovation and Easy Clip self-ligating bracket systems, the special Synergy brackets and Morelli's twin bracket with special 8-shaped elastomeric ligatures. New and used Morelli brackets with new and used elastomeric ligatures were used as control. All brackets had 0.022 x 0.028-in slots. 0.014-in nickel-titanium and stainless steel 0.019 x 0.025-in wires were tied to first premolar steel brackets using each archwire ligation method and pulled by an Instron machine at a speed of 0.5 mm/minute. Prior to the mechanical tests the absence of binding in the device was ruled out. Statistical analysis consisted of the Kruskal-Wallis test and multiple non-parametric analyses at a 1% significance level. RESULTS: When a 0.014-in archwire was employed, all ligation methods exhibited classical friction forces close to zero, except Morelli brackets with new and old elastomeric ligatures, which displayed 64 and 44 centiNewtons, respectively. When a 0.019 x 0.025-in archwire was employed, all ligation methods exhibited values close to zero, except the In-Ovation brackets, which yielded 45 cN, and the Morelli brackets with new and old elastomeric ligatures, which displayed 82 and 49 centiNewtons, respectively. CONCLUSIONS: Damon MX, Easy Clip, Smart Clip, Synergy bracket systems and 8-shaped ligatures proved to be equally effective alternatives for controlling classical friction using 0.014-in nickel-titanium archwires and 0.019 x 0.025-in steel archwires, while the In-Ovation was efficient with 0.014-in archwires but with 0.019 x 0.025-in archwires it exhibited friction that was similar to conventional brackets with used elastomeric ligatures.

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OBJECTIVE: To evaluate the stability and the relapse of maxillary anterior crowding treatment on cases with premolar extraction and evaluate the tendency of the teeth to return to their pretreatment position. METHODS: The experimental sample consisted of 70 patients of both sex with an initial Class I and Class II maloclusion and treated with first premolar extractions. The initial mean age was 13,08 years. Dental casts' measurements were obtained at three stages (pretreatment, posttreatment and posttreatment of 9 years on average) and the variables assessed were Little Irregularity Index, maxillary arch length and intercanine. Pearson correlation coefficient was used to know if some studied variable would have influence on the crowding in the three stages (LII1, LII2, LII3) and in each linear displacement of the Little irregularity index (A, B, C, D, E) in the initial and post-retention phases. RESULTS: The maxillary crowding relapse ( LII3-2) is influenced by the initial ( LII1), and the teeth tend to return to their pretreatment position. CONCLUSION: The results underline the attention that the orthodontist should be given to the maxillary anterior relapse, primarily on those teeth that are crowded before the treatment.

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OBJECTIVE: This study aimed to evaluate the cephalometric effects promoted by the orthodontic treatment of Class II malocclusion patients with the use of the 10-Hour Force Theory, that consists in the use of fixed appliances with 8 hours a day using a cervical headgear appliance and 16 hours a day using Class II elastics, 8 hours on the first mandibular molar and 8 hours in the second mandibular molar. METHODS: Sample comprised 31 patients with mean initial age of 14.90 years, final mean age of 17.25 years and mean treatment time of 2.35 years. The lateral cephalograms in pre-treatment and post-treatment stages were evaluated. Evaluation of cephalometric changes between initial and final treatment phases was performed by paired t test. RESULTS: The cases treated with the 10-Hour Force Theory presented a slight restriction of anterior displacement of the maxilla, increase in the effective length of the mandible, significant improvement of the maxillomandibular relationship, significant increase in anterior lower face height, distal tipping of the maxillary premolar crowns, extrusion and distal tipping of the roots of maxillary molars, significant proclination and protrusion of mandibular incisors, significant extrusion and mesialization of mandibular molars, besides a significant correction of the molar relationship, overjet and overbite. CONCLUSION: The use of the 10-Hour Force Theory in treatment of Class II malocclusion provided satisfactory results.

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A presente pesquisa avaliou a angulação mésio-distal e a distalização dos primeiros e dos segundos molares superiores permanentes em pacientes tratados com o aparelho Forsus® em conjunto com o aparelho ortodôntico fixo. A amostra foi composta por 44 teleradiografias, (22 do lado direito e 22 do lado esquerdo), obtidas por meio de 11 tomografias computadorizadas, de 11 pacientes, realizadas em dois tempos: antes (T1) e após (T2) a instalação do aparelho Forsus®, tratados na clínica de Pós-Graduação em Odontologia, área de Ortodontia, da Universidade Metodista de São Paulo. Após a obtenção dos cortes tipo telerradiografia, foi realizada a marcação dos pontos, linhas e planos, e realizada a mensuração das variáveis de interesse. Para avaliação do espaço para os terceiros molares superiores, utilizou-se uma linha referencial (linha PTVR), demarcada a partir do ponto PTV, perpendicular ao plano de Frankfurt. O espaço avaliado compreendeu entre a Linha PTVR, até a face distal do primeiro molar e do segundo superior permanente. Para avaliar o longo eixo dos primeiros e segundos molares superiores, mensurou-se o ângulo formado entre esses dentes e o plano palatino. Para auxílio das mensurações, foi utilizado o software Radiocef Studio 2. Na análise estatística usou-se o teste t pareado. Concluiu-se que houve distalização e aumento da angulação distal dos primeiros e segundos molares superiores, sendo que nos segundos molares a distalização e angulação distal da coroa ocorreram em menor quantidade; os efeitos do lado direito e esquerdo foram semelhantes; pode-se também constatar que ocorreu uma redução na probabilidade de erupção dos terceiros molares superiores.

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O objtivo deste estudo pros

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Under a Services Agreement dated 16th April 2010 the Australian Capital Territory (ACT) engaged Knowledge Consulting Pty Ltd to conduct an independent review of operations at the Alexander Maconochie Centre (AMC) in the ACT. The Review was commissioned following a motion passed in the ACT Legislative Assembly as follows: “That this Assembly: (1) notes: (a) concerns regarding the operation of the AMC; (b) the unanimous findings of the Standing Committee on Justice and Community Safety report, Inquiry into the delay in the commencement of operations at the Alexander Maconochie Centre; and (c) the Government’s intention to have a review into the operation of the AMC after its first year of operation; and (2) calls on the Government to: (a) commission an independent reviewer to conduct the one year review into the AMC; (b) ensure that the review be open and transparent and public, and include input from community and non-government groups with an interest or involvement in the AMC, including on the terms of reference for the review; (c) ensure the review is completed in a timely manner and be tabled in the Legislative Assembly immediately upon completion; and (d) report upon the progress of the review in August 2010;”

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Background: Adolescent idiopathic scoliosis (AIS) is a deformity of the spine, which may 34 require surgical correction by attaching a rod to the patient’s spine using screws 35 implanted in the vertebral bodies. Surgeons achieve an intra-operative reduction in the 36 deformity by applying compressive forces across the intervertebral disc spaces while 37 they secure the rod to the vertebra. We were interested to understand how the 38 deformity correction is influenced by increasing magnitudes of surgical corrective forces 39 and what tissue level stresses are predicted at the vertebral endplates due to the 40 surgical correction. 41 Methods: Patient-specific finite element models of the osseoligamentous spine and 42 ribcage of eight AIS patients who underwent single rod anterior scoliosis surgery were 43 created using pre-operative computed tomography (CT) scans. The surgically altered 44 spine, including titanium rod and vertebral screws, was simulated. The models were 45 analysed using data for intra-operatively measured compressive forces – three load 46 profiles representing the mean and upper and lower standard deviation of this data 47 were analysed. Data for the clinically observed deformity correction (Cobb angle) were 48 compared with the model-predicted correction and the model results investigated to 49 better understand the influence of increased compressive forces on the biomechanics of 50 the instrumented joints. 51 Results: The predicted corrected Cobb angle for seven of the eight FE models were 52 within the 5° clinical Cobb measurement variability for at least one of the force profiles. 53 The largest portion of overall correction was predicted at or near the apical 54 intervertebral disc for all load profiles. Model predictions for four of the eight patients 55 showed endplate-to-endplate contact was occurring on adjacent endplates of one or 56 more intervertebral disc spaces in the instrumented curve following the surgical loading 57 steps. 58 Conclusion: This study demonstrated there is a direct relationship between intra-59 operative joint compressive forces and the degree of deformity correction achieved. The 60 majority of the deformity correction will occur at or in adjacent spinal levels to the apex 61 of the deformity. This study highlighted the importance of the intervertebral disc space 62 anatomy in governing the coronal plane deformity correction and the limit of this 63 correction will be when bone-to-bone contact of the opposing vertebral endplates 64 occurs.

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This paper proposes a novel decision making framework for optimal transmission switching satisfying the AC feasibility, stability and circuit breaker (CB) reliability requirements needed for practical implementation. The proposed framework can be employed as a corrective tool in day to day operation planning scenarios in response to potential contingencies. The switching options are determined using an efficient heuristic algorithm based on DC optimal power flow, and are presented in a multi-branch tree structure. Then, the AC feasibility and stability checks are conducted and the CB condition monitoring data are employed to perform a CB reliability and line availability assessment. Ultimately, the operator will be offered multiple AC feasible and stable switching options with associated benefits. The operator can use this information, other operating conditions not explicitly considered in the optimization, and his/her own experience to implement the best and most reliable switching action(s). The effectiveness of the proposed approach is validated on the IEEE-118 bus test system. (C) 2015 Elsevier B.V. All rights reserved.

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Rabi oscillation of the thin bulk semiconductor GaAs, which takes into account the effect of the local-field correction induced by the interacting excitons, is investigated by numerically solving the semiconductor Bloch equations. It is found, for a 2 pi few-cycle pulse excitation, that two incomplete Rabi-floppings emerge due to the competition between the Rabi frequency of the incident pulse and the internal-field matrices. Furthermore, for a sub-cycle 2 pi pulse excitation a complete Rabi-flopping can occur because of the absolute phase effect. We ascribe these characteristics of the Rabi oscillation to the renormalized Rabi frequency.

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Pacientes portadores de deformidades dentofaciais podem relatar dificuldades de mastigação e fala, desordens temporomandibulares, preocupação com a imagem corporal e baixa autoestima. Frequentemente, buscam tratamento orto-cirúrgico pela motivação de obter melhora notável nos aspectos estético, funcional e psicossocial. A evidência atualmente disponível sobre os benefícios na qualidade de vida relacionada à saúde bucal desta modalidade terapêutica ainda não é conclusiva, devido à diversidade de metodologias adotadas entre os estudos existentes, majoritariamente realizados na América do Norte, Europa, Oriente Médio e Ásia. Logo, é essencial utilizar instrumentos específicos para avaliar os efeitos desta modalidade de tratamento também na vida diária dos pacientes brasileiros. O propósito do presente estudo transversal foi determinar o impacto que o tratamento orto-cirúrgico exerce sobre a percepção de qualidade de vida dos pacientes portadores de deformidades dentofaciais, bem como a influência exercida pelo gênero, idade, renda, escolaridade e características da má oclusão, nas quatro etapas inerentes a esta modalidade de tratamento: (1) Inicial; (2) Preparo ortodôntico para a cirurgia; (3) Pós-cirúrgico; e (4) Contenção (pós-tratamento). Duzentos e cinquenta e quatro pacientes foram entrevistados em três importantes centros de atendimento na cidade do Rio de Janeiro. A qualidade de vida foi avaliada pelos questionários OHIP-14 (Oral Health Impact Profile - Short Version) e pelo OQLQ (Orthognathic Quality of Life Questionnaire) em suas versões traduzidas e validadas para o português. A gravidade da má oclusão e autopercepção estética foram avaliadas com base no Índice de Necessidade de Tratamento Ortodôntico (IOTN) e pelo Índice de Estética Dental (DAI). A análise dos dados foi efetuada pelos testes qui-quadrado, Kruskal-Wallis e modelos de regressão binomial negativa múltipla. Os pacientes dos quatro grupos foram semelhantes em relação ao gênero (p = 0,463), escolaridade (p = 0,276) e renda familiar (p = 0,100). Entre os entrevistados houve o predomínio de mulheres, com ensino médio completo e renda familiar entre 2 e 3 salários mínimos, portadores de má oclusão de Classe III de Angle grave. No modelo de regressão binomial negativa ajustado para os fatores gênero, idade, renda familiar e escolaridade, a qualidade de vida aferida pelo OHIP-14 demonstrou que o grupo Inicial sofreu impactos mais negativos do que os grupos Pós-cirúrgico, Preparo e Contenção; o OQLQ indicou que o grupo Inicial sofreu impactos mais negativos do que os grupos Preparo, Pós-cirúrgico e Contenção, nesta sequência. Não foi detectada influência da idade, renda e escolaridade nestes resultados. Foi observado que o gênero feminino sofreu mais impacto negativo na qualidade de vida, principalmente nas dimensões relativas à função e a aspectos sociais. Concluiu-se que os pacientes que finalizaram o tratamento orto-cirúrgico apresentaram como benefícios menores impactos na qualidade de vida específica e relacionada à saúde bucal, melhor autopercepção estética e menor gravidade da má oclusão, em comparação aos pacientes nas etapas pré e pós-cirúrgica e aos pacientes portadores de deformidades dentofaciais em busca de tratamento.

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BackgroundAnterior open bite occurs when there is a lack of vertical overlap of the upper and lower incisors. the aetiology is multifactorial including: oral habits, unfavourable growth patterns, enlarged lymphatic tissue with mouth breathing. Several treatments have been proposed to correct this malocclusion, but interventions are not supported by strong scientific evidence.ObjectivesThe aim of this systematic review was to evaluate orthodontic and orthopaedic treatments to correct anterior open bite in children.Search methodsThe following databases were searched: the Cochrane Oral Health Group's Trials Register (to 14 February 2014); the Cochrane Central Register of Controlled Trials (CENTRAL)(The Cochrane Library 2014, Issue 1); MEDLINE via OVID (1946 to 14 February 2014); EMBASE via OVID (1980 to 14 February 2014); LILACS via BIREME Virtual Health Library (1982 to 14 February 2014); BBO via BIREME Virtual Health Library (1980 to 14 February 2014); and SciELO (1997 to 14 February 2014). We searched for ongoing trials via ClinicalTrials.gov (to 14 February 2014). Chinese journals were handsearched and the bibliographies of papers were retrieved.Selection criteriaAll randomised or quasi-randomised controlled trials of orthodontic or orthopaedic treatments or both to correct anterior open bite in children.Data collection and analysisTwo review authors independently assessed the eligibility of all reports identified.Risk ratios (RRs) and corresponding 95% confidence intervals (CIs) were calculated for dichotomous data. the continuous data were expressed as described by the author.Main resultsThree randomised controlled trials were included comparing: effects of Frankel's function regulator-4 (FR-4) with lip-seal training versus no treatment; repelling-magnet splints versus bite-blocks; and palatal crib associated with high-pull chincup versus no treatment.The study comparing repelling-magnet splints versus bite-blocks could not be analysed because the authors interrupted the treatment earlier than planned due to side effects in four of ten patients.FR-4 associated with lip-seal training (RR = 0.02 (95% CI 0.00 to 0.38)) and removable palatal crib associated with high-pull chincup (RR = 0.23 (95% CI 0.11 to 0.48)) were able to correct anterior open bite.No study described: randomisation process, sample size calculation, there was not blinding in the cephalometric analysis and the two studies evaluated two interventions at the same time. These results should be therefore viewed with caution.Authors' conclusionsThere is weak evidence that the interventions FR-4 with lip-seal training and palatal crib associated with high-pull chincup are able to correct anterior open bite. Given that the trials included have potential bias, these results must be viewed with caution. Recommendations for clinical practice cannot be made based only on the results of these trials. More randomised controlled trials are needed to elucidate the interventions for treating anterior open bite.