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AIM: To evaluate the maxillary incisors and canine's immediate movement tendency using three different power arms (PA) height levels during total arch maxillary distalization supported on infrazygomatic crest (IZC) miniscrews according to finite element analysis (FEA). METHODS: Three finite element models of the maxilla were developed based on CBCT imaging of a teenage male patient presenting a Class II Division 1 malocclusion in the early permanent dentition. Maxillary complex, periodontium, orthodontic accessories, IZC miniscrews and an orthodontic wire were digitally created. The PAs were placed between canines and lateral incisors and projected at 4, 7, and 10 mm height distances. After that, distalization forces were simulated between PA and IZC miniscrews. RESULTS: The anterior teeth deformation produced in the FEA models was assessed according to a Von Mises equivalent. The stress was measured, revealing tendencies of initial maxillary teeth movement. No differences were found between the right and left sides. However, there was a significant difference among models in the under-stress areas, especially the apical and cervical root areas of the maxillary anterior teeth. More significant extrusion and lingual tipping of incisors were observed with the 4 mm power arm compared to the 7 mm and 10 mm ones. The 10 mm power arm did not show any tendency for extrusion of maxillary central incisors but a tendency for buccal tipping and intrusion of lateral incisors. CONCLUSION: The maxillary incisors and canines have different immediate movement tendencies according to the height of the anterior point of the en-masse distalization force application. Based on the PA height increase, a change from lingual to buccal tipping and less extrusion tendency was observed for the incisors, while the lingual tipping and extrusion trend for canines increased.

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The objective of present research was to propose a new definition for the midpalatal suture (MPS) maturational stages through reevaluation of intermediate stages B, C and D. The sample was composed by 158 cone-beam computed tomography (CBCT) of individuals between 11 and 20 years of age (±15.4 years, 86 females and 71 males), divided into two groups: 74 individuals aged 11-15 years and 84 individuals aged 16-20 years. The CBCT scans were applied to evaluate midpalatal suture maturation status and comprised stages previously classified as B (29), C (92) and D (37). Each axial image was subdivided into six parts in the anteroposterior direction, and each portion was classified according to MPS maturational evaluation methodology. New definitions of stages were proposed. The reliability of the method was tested by two examiners and the intra- and inter-examiner concordances were defined for each evaluation through weighted kappa coefficients and 95% confidence intervals. The chi-square test was used to compare the groups. In all statistical tests, a significance level of 5% was adopted. Two new maturational stages were defined: sub-stage C- and sub-stage C+, with prevalence of 12% and 8.9%, respectively, in 11 to 20-year-olds. The redefinition and validation of the maturational stages of MPS, considering the sub-stages C- and C+, may allow to elucidate the difference in the prognosis of Rapid Maxillary Expansion among individuals aged 11 to 20 years. This data should be confirmed through a clinical study.(AU)

O objetivo da presente pesquisa foi propor uma nova definição para os estágios maturacionais da sutura palatina média (MPS) por meio da reavaliação dos estágios intermediários B, C e D. A amostra foi composta por 158 tomografias computadorizadas de feixe cônico (TCFC) de indivíduos entre 11 e 20 anos de idade (±15,4 anos, 86 do sexo feminino e 71 do sexo masculino), divididos em dois grupos: 74 indivíduos de 11 a 15 anos e 84 indivíduos de 16 a 20 anos. Os exames de TCFC foram aplicados para avaliar o estado de maturação da sutura palatina média e compreenderam os estágios previamente classificados como B (29), C (92) e D (37). Cada imagem axial foi subdividida em seis partes no sentido anteroposterior, e cada porção foi classificada de acordo com a metodologia de avaliação maturacional MPS. Novas definições de estágios foram propostas. A confiabilidade do método foi testada por dois examinadores e as concordâncias intra e interexaminadores foram definidas para cada avaliação por meio de coeficientes kappa ponderados e intervalos de confiança de 95%. O teste do qui-quadrado foi utilizado para comparar os grupos. Em todos os testes estatísticos adotou-se o nível de significância de 5%. Dois novos estágios maturacionais foram definidos: subestágio C- e subestágio C+, com prevalência de 12% e 8,9%, respectivamente, em jovens de 11 a 20 anos. A redefinição e validação dos estágios maturacionais da MPS, considerando os subestágios C- e C+, podem permitir elucidar a diferença no prognóstico da Expansão Rápida da Maxila entre indivíduos de 11 a 20 anos. Esses dados devem ser confirmados por meio de um estudo clínico.(AU)

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Esse estudo propectivo teve como objetivo realizar a avaliação das alterações dentoalveolares em modelos digitais de pacientes cuja mordida aberta anterior foi tratada seguindo dois protocolos distintos: esporão lingual e mentoneira. A amostra foi composta por 41 pacientes (27 do sexo feminino e 14 do sexo masculino) com idades entre 7-10 anos (média de idade de 8.37 anos), dentição mista com diagnóstico de mordida aberta anterior (média de -3.43mm) e tratados ao longo de um ano. Os pacientes foram aleatoriamente dividiso em dois grupos de acordo com a terapia realizada: Grupo 1 (n=23) tratados com esporão lingual, e Grupo 2 (n=18) tratados com mentoneira pré-fabricada. Os modelos de gesso foram escaneados, gerando uma imagem tridimensionao em qual as medidas foram realizadas em 2 tempos distintos: T1 (imediatamente antes do tratamento) e T2 (um ano após o início do tratamento). Alteraçnoes transversais, comprimento e perímetro dos arcos dentários superior e inferior, trespasse horizontal e vertical, assim como inclinação dos incisivos centrais foram avaliadas. O Coeficiente de Correlação Interclasse (CCI) e o método Bland-Altman foram aplicados para verificar o erro intra examinador. Os resultados foram analisados através do Teste T pareado e independente adotando uma significância de 5%. Após um ano de tratamento, observou-se alerações estatisticamente significantes em todas as variáveis, exceto perímetro e comprimento dos arcos superio e inferior, inclinação do incisivo central superior e trespasse horizontal. As alterações enre os grupos (T2-T1) apresentaram resultados similares. Concluiu-se que ambos os protocolos apresentaram mudanças semelhantes na mordiada aberta anterior após um ano de tratamento.(AU)

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OBJECTIVE: Compare changes in arch form after RME achieved by Expander with Differential Opening (EDO), Hyrax-type and Haas-type expanders. MATERIALS AND METHODS: Dental models were obtained from 61 patients aged 7-11 years before expansion (T1) and 6 months after the active phase when the appliances were removed (T2). The groups were formed according to the expander used: EDO (n = 18, mean age: 9.46 ± 0.82 years), Hyrax-type (n = 22, mean age: 9.62 ± 1.57 years) and Haas-type (n = 21, mean age: 9.29 ± 1.05 years). The expander`s activation protocol consisted of 7 mm, except for EDO`s anterior screw, which was 9 mm. The measurements of upper and lower intercanine distance, inter-first permanent molar, arch perimeter and length, maxillary canine and first-permanent molar inclination, and palatal depth were performed using the OrthoAnalyzer 3D software. Intergroup comparisons of T1 and between changes (T2-T1) were performed using ANOVA followed by Tukey. RESULTS: In the upper intercanine distance EDO provided a greater increase than Haas-type. In the distance between upper fist permanent molars EDO showed higher values than Haas-type and Hyrax-type. In the lower intercanine distance and maxillary arch length, Haas-type promoted higher increase than EDO. CONCLUSIONS: The EDO promoted greater transverse changes in anterior region than Haas-type and greater transverse changes in posterior region of the maxilla than both conventional expanders. The appliance used for RME influences dental arch changes after treatment; therefore, it is recommended to individualize the choice of expander depending on the clinical necessity of each case.

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The objective of this study was to evaluate the tooth crown inclination in maxillary and mandibular arches in Class III malocclusion individuals, to identify the presence and magnitude of compensation. The study was conducted on 46 plaster casts of individuals with Class III malocclusion, of both genders (25 males and 21 females), with mean age 21 years and 1 month, with indication for compensatory orthodontic treatment. The dental casts models were scanned and the tooth crown inclinations were measured and compared with standard values by the independent t test. All tests considered a significance level of 5% (p<0.05). According to the results there was extensive variation in tooth inclination in Class III malocclusions. Values distribution for incisors highlighted the significant concentration of maxillary incisors in the area of positive values, compared with a very expressive concentration of mandibular incisors in the area of negative values. Compared with normal standards, in Class III malocclusions, the maxillary posterior teeth exhibited smaller palatal inclination than normal, while the mandibular incisors and second molars presented greater lingual inclination. It was concluded that the analysis of inclinations of all crowns of both dental arches in Class III malocclusions, compared with normal standards, evidenced the presence of natural compensation for maxillary posterior teeth, with reduced palatal inclination, as well as increased lingual inclination in mandibular incisors. The parameters of compensation naturally present in Class III malocclusions described, especially in lower incisors, would help clinicians when compensatory treatment is considered. (AU)

O objetivo deste estudo foi avaliar a inclinação das coroas dentárias nas arcadas superior e inferior em indivíduos com má oclusão de Classe III, para identificar a presença e a magnitude da compensação. O estudo foi realizado em 46 modelos de gesso de indivíduos com má oclusão de Classe III, de ambos os sexos (25 homens e 21 mulheres), com média de idade de 21 anos e 1 mês, com indicação de tratamento ortodôntico compensatório. Os modelos de gesso foram digitalizados e as inclinações da coroa dos dentes foram medidas e comparadas com os valores de normalidade pelo teste t independente. Todos os testes estatísticos adotaram um nível de significância de 5% (p <0,05). De acordo com os resultados, houve grande variação na inclinação dentária nas más oclusões de Classe III. A distribuição dos valores para os incisivos destacou a concentração significativa de incisivos superiores na área de valores positivos, em comparação com uma concentração muito expressiva de incisivos inferiores na área de valores negativos. Comparados aos padrões de normalidade, nas más oclusões de Classe III, os dentes posteriores superiores exibiram inclinação palatina menor que o normal, enquanto os incisivos e segundos molares inferiores apresentaram inclinação lingual maior. Concluiu-se que a análise das inclinações de todas as coroas de ambas as arcadas dentárias nas más oclusões de Classe III, comparadas aos padrões de normalidade, evidenciou a presença de compensação natural para os dentes posteriores superiores, com diminuição da inclinação palatina, bem como aumento da inclinação lingual dos incisivos inferiores. Os parâmetros de compensação naturalmente presentes nas más oclusões de Classe III descritos, especialmente nos incisivos inferiores, podem auxiliar o clínico quando o tratamento compensatório é considerado. (AU)

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INTRODUCTION: This study aimed to compare the 2 most commonly used methods for assessing facial pleasantness, the Likert scale and the visual analog scale (VAS). METHODS: For assessing facial pleasantness, an album was assembled containing the front and profile view facial photographs of 10 patients (5 females, 5 males) who sought orthodontic treatment representing each of the different sagittal and vertical facial discrepancies (straight profile, convex profile, concave profile, long faces, and short faces). The facial pleasantness of the patients was judged by 3 groups of 90 evaluators (47 females and 43 males): 30 orthodontists (mean age, 32.41 years), 30 oral maxillofacial surgeons (mean age, 36.83 years), and 30 laypeople (mean age, 36.83 years). The evaluators judged the facial pleasantness using VAS and a 5-point Likert scale. At the end of the evaluation, the evaluators completed a questionnaire about their preferred scale. Analysis of variance and Tukey and Kruskal-Wallis tests were used to compare the data from VAS and Likert scale, respectively. The Spearman correlation coefficient was used to estimate the correlation between the 2 scales. Fisher transformation and z-statistic were used to estimate the correlation among the evaluator groups. In all tests, a 5% statistical significance level was adopted. RESULTS: Both scales presented similar answers; only VAS values for the scores of pleasant and very pleasant according to the Likert scale could not be distinct. Most evaluators preferred the Likert scale as they found it easier to convey their opinion than VAS. CONCLUSIONS: Although both scales can be used to assess facial pleasantness, the Likert scale seems more appropriate as the evaluators preferred it because of its simplicity.

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OBJECTIVE: To compare the magnitude of external apical root resorption (EARR) 6 months after starting orthodontic treatment using orthodontic aligners (OAs) and fixed appliances (FAs). METHODS: This parallel randomized clinical trial included 40 patients randomized into two groups: OA group (n = 20, 160 incisors) and FA group (n = 20, 160 incisors). For evaluation of the tooth length, periapical radiographs and standardized linear measurements of the maxillary and mandibular incisors were acquired before (T0) and 6 months after treatment initiation (T1). EARR was calculated through the difference in length between the two time points (T1-T0). Statistical comparisons were performed by means of using t-tests, chi-squared test and covariance analysis (a = 5%). RESULTS: Rounding of the root apex was observed in both groups; the resorption involved 2.88% of the root length, so 97.12% of the tooth length remained intact. Intragroup comparisons between the two time points revealed a significant difference, with (T1-T0) ranging from -0.52 to -0.88 mm in the FA group and from -0.52 to -0.85 mm in the OA group. In the intergroup comparisons, only tooth #21 presented a statistically significant difference (OA: -0.52 ± 0.57 mm, FA: -0.86 ± 0.60 mm); however, the overall differences between groups were not clinically relevant, ranging from 0.03 to 0.35 mm. CONCLUSIONS: OA and FA treatment resulted in a similar degree of EARR in the maxillary and mandibular incisors at 6 months after treatment initiation. However, the amount of resorption was small and does not impair tooth longevity.

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Extrusive tooth movements are an important resource in orthodontic treatment and allow the manipulation of teeth and periodontal tissues. They can be performed quickly or slowly, depending on the patient's need. Rapid extrusion is indicated for cases in need of prosthetic preparation or restoration, where the bone and gingival tissues are intact, such as horizontal and oblique fractures, coronary or external root resorption, iatrogenic perforations (trepanations) and the presence of subgingival caries. The aim of this study is to describe the treatment of a patient who had a coronary fracture of the right upper central incisor, with a limit located 1 mm above the level of the bone crest. Rapid orthodontic extrusion was performed, to restore biologic distances and allow the preparation for prosthesis. It started with partial differentiated bonding of a fixed orthodontic appliance to the upper arch, to allow for a 3mm orthodontic extrusion. At the end of the extrusion, periodontal surgery was performed to increase the clinical crown and endodontic treatment. After these procedures, the case was concluded with the fixed prosthesis installation. The realization of an integrated planning allowed the restoration of aesthetics, with preservation of the functional periodontal limits for the patient.(Au)

Os movimentos dentários extrusivos constituem um recurso importante no tratamento ortodôntico e permitem a manipulação dos dentes e dos tecidos periodontais. Eles podem ser realizados de forma rápida ou lenta, dependendo da necessidade do paciente. A extrusão rápida está indicada para casos com necessidade de preparo protético ou restauração, onde os tecidos ósseo e gengival encontram-se íntegros, tais como fraturas horizontais e oblíquas, reabsorções coronárias ou radiculares externas, perfurações iatrogências (trepanações) e presença de cárie subgengival. O objetivo deste trabalho é descrever o tratamento de uma paciente que apresentava fratura coronária do incisivo central superior direito, com limite localizado 1mm acima do nível da crista óssea. Realizou se extrusão ortodôntica rápida, com a finalidade de restabelecer as distâncias biológicas e permitir o preparo para prótese. Iniciou-se com colagem diferenciada parcial de aparelho ortodôntico fixo no arco superior, para permitir a extrusão ortodôntica de 3mm. Ao término da extrusão, realizou-se cirurgia periodontal para aumento da coroa clínica e tratamento endodôntico. Após esses procedimentos, o caso foi finalizado com a instalação da prótese fixa. A realização de um planejamento integrado permitiu o restabelecimento da estética, com preservação dos limites periodontais funcionais para a paciente. (Au)

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Dentists are healthcare professionals who are at high risk of infection and transmission of the coronavirus disease-19 (COVID-19). The primary objective of the present study was to evaluate the changes in clinical practice made by Brazilian dentists during the COVID-19 pandemic. From June 22 to July 13, 2020, an online questionnaire was sent to dentists using Google Forms. After providing consent, 1,178 dentists answered questions regarding their knowledge and clinical experiences related to COVID-19. Data were analyzed using Chi-square, Fisher's exact, or Kruskal-Wallis tests, with a significance level of 5%. Brazilian dentists significantly changed their routine dental practices. Biosafety measures were added in their offices by 98% of the dentists, increasing operating costs for 88.3% of dentists. Greater discomfort due to the increase in personal protection equipment (PPE) worn during the pandemic was reported by 58.6%. Furthermore, 84.2% reduced heir hours of service. It was found that the dentists decreased their workload, used additional PPE, and took additional biosafety measures.

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OBJECTIVE: This randomized clinical trial aimed to compare the pain intensity in patients treated with orthodontic aligners and conventional fixed appliances. SETTING AND SAMPLE POPULATION: This study was a randomized clinical trial. The sample comprised 39 patients randomly allocated into 2 groups: OA (orthodontic aligners, n = 20) and FA (Fixed Appliance, n = 19). MATERIAL AND METHODS: The pain intensity was measured by the visual analogue scale (VAS) in the following periods: T0 (baseline), T1 (seven days after appliance placement) and seven days after each return on the first (T2), third (T3) and sixth (T4) months. The following variables were also investigated in the baseline: conditioned pain modulation, anxiety levels, hypervigilance and catastrophizing. The VAS measurements between groups were compared by the Mann-Whitney test. Comparisons between periods within each group were performed by the Friedman test. Data regarding catastrophizing and hypervigilance were compared by the t test. All tests were applied at a significance level of 5%, with 95% confidence interval. RESULTS: Both groups presented similar levels of anxiety, hypervigilance, catastrophizing and conditioned pain modulation. Both groups did not differ concerning the pain intensity in all periods. The intragroup evaluation revealed statistical differences between days in the FA group at all moments evaluated, for the OA group, similar findings between days were found for the T1 evaluation; however, at the 6-month period (T4), the pain levels varied over these days without statistical difference. Higher levels of pain were observed in the first seven days after appliance placement. CONCLUSION: The pain intensity, usually mild, was not influenced by the appliance design, although different patterns of reported pain seem to occur between groups.

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