Abstract Pain is common in orthodontic treatment, is subject to individual variation, and is associated with anxiety and stress, which can potentially become catastrophizing. The aim of the present study was to determine the variability of pain response after the insertion of orthodontic separators and to assess the association of pain levels with dental anxiety, catastrophizing, tooth sensitivity, and genetic expression of cytokines. To this end, 70 patients of both genders were divided into two equal groups according to the elastomeric separator used: G1 (Dentaurum) and G2 (Orthometric). Two separators were inserted in the mesial and distal sides of the lower right first molar. Participants were instructed to rate the level of pain at T0 (before insertion), T1 (just after insertion), and T2 (24 hours after insertion) on a visual analog scale. The gingival crevicular fluid was collected at T0 and T2. The levels of anxiety, catastrophizing, tooth sensitivity, and cytokine expression were also assessed. Statistical analysis was performed with the Fisher-Freeman-Halton, chi-squared, Spearman’s correlation, and dependent and independent t tests (α=5%). Pain intensity was higher at T2 than at T1, in both groups (P<.05). An association was established (P<.05) between pain intensity at T1 and catastrophizing, and at T2 with anxiety and catastrophizing. Within-group differences in cytokine expression were found between T0 and T2. There was no correlation between cytokine expression and pain levels, anxiety, catastrophizing, and sensitivity at T2. Tooth separation produced variable pain levels, which were influenced by anxiety and catastrophizing, however, pain level was not correlated with increased cytokine expression.

ABSTRACT Objective: The aim of this study was to test the null hypothesis that there is no difference at the midpalatal suture opening after rapid maxillary expansion (RME) using Expander with Differential Opening (EDO), Hyrax-type and Haas-type expanders. Methods: Occlusal radiographs of 52 patients (19 males and 33 females; average age= 9.46?1.20 years) treated with RME were divided into three groups, according to the expander used: EDO (n=17), Hyrax-type (n=21) and Haas-type (n=14). The evaluated variables were: A) Distance between the maxillary central incisors at the incisal edge; B) Distance between the alveolar ridges at the midpalatal suture; C) Suture opening at 10-mm distance from the crest to posterior, at the midpalatal suture; D) Suture opening at 20-mm distance from the crest to posterior, at the midpalatal suture; and E) Suture opening at 30-mm distance from the crest to posterior, at the midpalatal suture. To assess the normality of variables, the Shapiro-Wilk test was performed. For intergroup comparison, ANOVA with a significance level of 5% was used. Results: At the region A, Hyrax-type (4.66 mm) and EDO (4.87 mm) groups presented larger openings than the Haas-type group (3.43 mm). In regions B and C, EDO showed a statistically significant greater opening than the Haas-type group. In region D, a smaller opening of the midpalatal suture was observed in the Haas-type group, compared to the Hyrax-type and EDO groups. Conclusions: EDO and Hyrax-type produced greater immediate skeletal effects, compared with Haas-type, but these differences were about 1 mm and might not be clinically significant.

RESUMO Objetivo: O objetivo do presente estudo foi testar a hipótese nula de que não existe diferença na abertura da sutura palatina mediana após a expansão rápida da maxila (ERM) usando os expansores Diferencial, tipo Hyrax e tipo Haas. Métodos: Radiografias oclusais de 52 pacientes (19 do sexo masculino e 33 do sexo feminino; idade média: 9,46 ? 1,20 anos) tratados com ERM foram divididas em três grupos, de acordo com o tipo de expansor usado: Diferencial (n = 17), tipo Hyrax (n = 21) e tipo Haas (n = 14). As variáveis avaliadas foram: A) distância entre os incisivos centrais superiores na borda incisal; B) distância entre os rebordos alveolares na sutura palatina mediana; C) abertura da sutura a 10 mm de distância da crista para posterior, na sutura palatina mediana; D) abertura da sutura a 20 mm da crista para posterior, na sutura palatina mediana; e E) abertura da sutura a 30 mm da crista para posterior, na sutura palatina mediana. Para verificar a normalidade das variáveis, utilizou-se o teste de Shapiro-Wilk. Para comparação intergrupos, usou-se a ANOVA com nível de significância de 5%. Resultados: Na região A, os grupos tipo Hyrax (4,66 mm) e Diferencial (4,87 mm) apresentaram uma abertura maior do que o grupo tipo Haas (3,43 mm). Nas regiões B e C, o Diferencial mostrou abertura significativamente maior do que o grupo tipo Haas. Na região D, uma abertura menor da sutura palatina mediana foi observada no grupo tipo Haas, comparado aos grupos tipo Hyrax e Diferencial. Conclusões: Os expansores Diferencial e tipo Hyrax produziram maiores efeitos esqueléticos imediatos, comparados ao tipo Haas, mas essas diferenças foram de aproximadamente 1 mm e podem não ser clinicamente significativas.

Resumo Os objetivos do presente estudo foram comparar e avaliar a estabilidade do tratamento precoce da mordida aberta anterior (MAA) com diferentes dispositivos. A amostra inicial foi composta por 99 pacientes randomizados em quatro grupos experimentais: BS - esporões colados; CC - mentoneira; FPC - grade palatina fixa; RPC - grade palatina removível. Análise cefalométrica foi realizada para avaliar os dados do período inicial (T1), final do tratamento (T2) e 2 anos após tratamento (T3), sendo a variável overbite o desfecho principal. Em T3, após perdas de seguimento, haviam 63 indivíduos, sendo BS (n=15; overbite 0.19 mm; 11.54 anos; 10 Feminino (F)/5 Masculino (M)); CC (n=11; overbite -0.19 mm; 11.41 anos; 8 F/3 M); FPC (n=21; overbite 1.23 mm; 11.44 anos; 15 F/6 M) e; RPC (n=16; overbite 0.73 mm; 11.67 anos; 6 F/10 M). Comparações das alterações nas variáveis dentoesqueléticas e abandono de hábitos bucais deletérios durante o tempo de acompanhamento foram estatisticamente analisados com p<.05. Medidas esqueléticas lineares mandibulares e componentes verticais aumentaram gradualmente com a idade, principalmente com o surto de crescimento puberal e estabelecimento da dentição permanente no pós-tratamento. O overbite foi significantemente melhorado durante o tratamento, permanecendo estável com alterações positivas. A extrusão dos incisivos impactou na correção da MAA e estabilidade nos 4 grupos, que registraram uma melhora de 1.15 mm no pós-tratamento (T3-T2). Com suas limitações, todos dispositivos experimentais foram efetivos e mostraram resultados estáveis no tratamento precoce da MAA, sendo que a FPC apresentou a maior correção da MAA e o menor índice de desistência.

Abstract This 2-year-follow up study compared and evaluated the stability of early anterior open bite (AOB) treatment based on different appliances. Children from 7 to 10 years with Angle Class I, AOB larger than 1.0 mm and fully erupted maxillary and mandibular permanent central incisors were eligible. The initial sample was 99 patients distributed, by simple randomization, into four groups: BS (bonded spurs), CC (chincup), FPC (fixed palatal crib) and RPC (removable palatal crib). Cephalometric analysis was performed at baseline (T1), final (T2) and 2-year post-treatment (T3) by taking the overbite measurements as the main outcome. Blinding was possible to cephalometric analysis. At T3, with dropouts, there were 63 individuals, being BS (n=15; overbite 0.19 mm; 11.54 years; 10 female (F)/5 male (M)); CC (n=11; overbite -0.19 mm; 11.41 years; 8 F/3 M); FPC (n=21; overbite 1.23 mm; 11.44 years; 15 F/6 M) and; RPC (n=16; overbite 0.73 mm; 11.67 years; 6 F/10 M). Changes in dentoskeletal variables and breaking deleterious oral habits during the follow up were statically analyzed with p<.05. Mandibular skeletal linear measurements and vertical dental components have gradually increased with age, manly at pubertal growth spurt and at the establishment of permanent dentition after treatment. Incisor teeth extrusion had impact on AOB correction and stability in 4 groups, which recorded a 1.15 mm-improvement of overbite after treatment (T3-T2). The experimental appliances were effective with stable results, being FPC the device recorded the highest AOB correction and the lowest patient withdrawal rate.

RESUMO Objetivo: Realizar uma simulação numérica, por meio do Método dos Elementos Finitos (MEF), para obter as tensões de von Mises em arcos Mushroom. Métodos: Foram usados arcos com geometria Mushroom de titânio-molibdênio, com secção transversal 0,017” x 0,025”. Adotou-se valores de tensão de escoamento (σesc) de 1.240 MPa e módulo de elasticidade (E) de 69 GPa. O arco foi modelado por meio do software Autodesk Inventor, e seu desempenho foi simulado utilizando-se o software de elementos finitos Ansys Workbench (Swanson Analysis System, Houston, Pennsylvania, EUA). Para a simulação, foi considerada a análise para grandes deslocamentos. O arco foi conformado em suas extremidades considerando-se planos de 0° e 45°, pré-ativado em 2,5mm e ativado por meio de suas extremidades verticais, separadas 4,0 mm ou 5,0 mm. Resultados: As tensões revelaram um valor máximo de 1.158 MPa na maior parte da alça, aos 5,0 mm de ativação, com exceção de uma área muito pequena, com valor de 1.324 MPa, situada no topo da alça. Conclusões: Os arcos Mushroom são capazes de produzir níveis de tensão situados dentro da região elástica e poderiam ser ativados com segurança até os 5,0 mm de ativação.

ABSTRACT Objective: To perform a numerical simulation using FEM to study the von Mises stresses on Mushroom archwires. Methods: Mushroom archwires made of titanium-molybdenum alloy with 0.017 x 0.025-in cross-section were used in this study. A YS of 1240 MPa and a Young’s modulus of 69 GPa were adopted. The archwire was modeled in Autodesk Inventor software and its behavior was simulated using the finite element code Ansys Workbench (Swanson Analysis Systems, Houston, Pennsylvania, USA). A large displacement simulation was used for non-linear analysis. The archwires were deformed in their extremities with 0° and 45°, and activated by their vertical extremities separated at 4.0 or 5.0 mm. Results: Tensions revealed a maximum of 1158 MPa at the whole part of the loop at 5.0mm of activation, except in a very small area situated at the top of the loop, in which a maximum of 1324 Mpa was found. Conclusions: Mushroom loops are capable to produce tension levels in an elastic range and could be safely activated up to 5.0mm.

RESUMO Objetivo: o presente estudo in vitro avaliou, por meio da técnica de fotoelasticidade, os efeitos produzidos pelo Arco de Intrusão de Connecticut (CIA) com dobra de 90o na face distal dos tubos molares e usando um aparelho 4 x 2 nas regiões anterior e posterior da arcada dentária superior. Métodos: foram confeccionados cinco modelos, aos quais foram correlacionadas duas situações clínicas diferentes: 1) uso do arco de intrusão sem dobra distal, mas com barra transpalatina para ancoragem (G1); 2) uso do arco de intrusão com dobra distal e barra transpalatina para ancoragem (G2). Avaliou-se as tensões geradas nos terços apical e médio das raízes dos dentes anterossuperiores e primeiros molares superiores. Resultados: considerando-se um valor de referência de 1,0 MPa = 100%, foi realizada uma análise descritiva qualitativa, a qual demonstrou uniformidade entre os valores de tensão na região apical dos dentes anteriores nos dois grupos (G1 e G2). Na região posterior dos modelos com arcos com dobra distal (G2), a tensão foi mantida em 100%. Já nos modelos do G1 (arco sem dobra distal), foram observadas variações na face mesial dos primeiros molares, com um aumento de 20% na tensão gerada. A região apical não sofreu qualquer alteração, ao passo que, na região distal dos molares, houve uma diminuição de 20% na tensão. Conclusão: os resultados laboratoriais revelaram diferenças, entre os grupos 1 e 2, para a tensão gerada na região dos molares, indicando que houve uma tendência de mesialização da raiz dos primeiros molares quando não foi realizada a dobra na extremidade distal do CIA.

ABSTRACT Objective: The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Methods: Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Results: Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Conclusion: Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back.

Objetivo: avaliar a estabilidade da inclinação mesiodistal dos molares superiores cinco anos após o tratamento realizado com o aparelho Pendulum seguido de aparelho ortodôntico fixo. As mudanças na angulação foram comparadas com uma amostra não tratada. Métodos: a amostra consistiu de 20 pacientes (14 do sexo feminino e 6 do masculino) com má oclusão de Classe II, divisão 1 tratados por meio da distalização dos molares com o aparelho Pendulum seguido de ancoragem extrabucal cervical e aparelho fixo. A inclinação dos molares superiores foi avaliada por meio de radiografias panorâmicas. A média da idade ao início do tratamento foi de 14,3 ± 1,6 anos; ao final do tratamento, de 18,6 ± 1,8 anos e, no longo tempo pós-tratamento, de 23,8 ± 2,0 anos. Para comparação, foi usado um grupo controle com 16 indivíduos não tratados e com oclusão normal, apresentando idades entre 12 e 17 anos. Os dados foram analisados estatisticamente pelo teste t independente e ANOVA, seguido do teste de Tukey. Resultados: os primeiros molares superiores apresentaram diferenças estatisticamente significativas entre T1 (94,5o) e T2 (98,8o), bem como entre T2 e T3 (94,7o). Os segundos molares superiores não apresentaram alterações estatisticamente significativas no seu posicionamento durante os períodos avaliados, T1 (107,5o), T2 (109,3o) e T3 (106,9o). Conclusões: apesar de os primeiros molares superiores apresentarem inclinação distal da coroa imediatamente após o tratamento, aproximadamente cinco anos depois suas raízes tendem a ocupar posições próximas às do início do tratamento.

Objective: To evaluate the stability of mesiodistal inclination of maxillary molars produced by a pendulum appliance, five years after completion of orthodontic treatment. Angulation changes were compared to an untreated sample. Methods: The sample consisted of 20 patients (14 females and 6 males) with Class II, Division 1 malocclusion that was treated through molar distalization with a pendulum appliance followed by cervical headgear and full fixed appliances. Maxillary molar inclination was evaluated through panoramic radiograph. The mean age at pretreatment was 14.3 ± 1.6 years, whereas at immediate post-treatment it was 18.6 ± 1.8 years, and at long-term post-treatment it was 23.8 ± 2.0 years. A control group of 16 untreated individuals with untreated normocclusion ranging in age from 12 to 17 years old were used as comparison group. Data were statistically analyzed with independent t-tests and ANOVA test followed by Tukey post-hoc tests. Results: Statistically significant differences were found between T1 (94.50) and T2 (98.80) as well as between T2 and T3 (94.70) for maxillary first molars. Maxillary second molars did not show any statistically significant positional changes during the evaluated time periods T1 (107.50), T2 (109.30) and T3 (106.90). Conclusion: Although maxillary first molars underwent distal crown inclination immediately after treatment, approximately five years thereafter their roots tended to upright close to the pretreatment positions.

Abstract The aim of this study was to investigate condyle concentricity and morphology, and their association with Class I and II malocclusions (Angle). The sample consisted of 49 individuals of both genders, between 11 and 35 years old, divided into two groups, G1: 26 patients with Class I malocclusion, and G2: 23 patients with Class II malocclusion, selected for orthodontic treatment. Evaluation of the condyle morphology and position was performed by the same previously calibrated examiner using cone-beam computed tomography (CBCT) images of the subjects. The CBCT scans were analyzed by means of a 3D program (Dolphin 11.5, Dolphin Imaging & Management Solutions, Chatsworth, CA, USA), with a 25% level of sensitivity. The images obtained from the coronal slices were employed for the condyle morphology analysis, which classified the condyle form as rounded, as flat or convex, and as triangular or angled. The sagittal slices were used to classify further the condyles as concentric and displaced anteriorly or posteriorly. A clinical examination was also performed, including TMJ and muscle palpation. The kappa test was used to evaluate investigator calibration; the Chi-square and paired t-tests were used for analysis. The convex and anteriorly positioned condyles were found most frequently, regardless of the type of malocclusion. No association was observed between the groups regarding condylar characteristics.

OBJETIVO: o objetivo do presente estudo foi comparar as alterações dentoalveolares transversais e a espessura óssea da arcada inferior em pacientes submetidos ao tratamento ortodôntico utilizando sistemas de braquetes autoligáveis ou convencionais. MÉTODOS: uma amostra de 25 pacientes requerendo tratamento ortodôntico foi recrutada com base no tipo de braquete. No Grupo 1, 13 pacientes foram tratados com braquetes autoligáveis (SLB, slot 0,022"); o Grupo 2 incluiu 12 pacientes, nos quais foram colados braquetes convencionais (CLB, slot 0,022"). Utilizou-se tomografia computadorizada de feixe cônico e um programa 3D (Dolphin) para avaliar as alterações pré-tratamento (T1) e 7 meses após o início desse (T2). As medições em modelos de gesso foram realizadas com o auxílio de um paquímetro digital. As diferenças intergrupos, bem como intragrupo, foram analisadas por meio de teste t de Student. Além disso, o coeficiente de correlação de Pearson foi utilizado. RESULTADOS: alterações dentoalveolares significativas foram observadas em ambos os grupos. Entretanto, não houve diferenças significativas entre os grupos. Houve uma diminuição da espessura óssea na região posterior e das medidas transversais em ambos os grupos. Não houve uma correlação significativa entre a espessura óssea posterior e a expansão da arcada dentária, em nenhum dos dois sistemas de braquetes utilizados. CONCLUSÕES: comparando-se o uso dos aparelhos autoligáveis e convencionais, concluiu-se que não houve diferenças dentoalveolares significativas quanto à expansão da arcada inferior e quanto à espessura óssea posterior.

OBJECTIVE: The aim of the present study was to compare dentoalveolar changes in mandibular arch, regarding transversal measures and buccal bone thickness, in patients undergoing the initial phase of orthodontic treatment with self-ligating or conventional bracket systems. METHODS: A sample of 25 patients requiring orthodontic treatment was assessed based on the bracket type. Group 1 comprised 13 patients bonded with 0.022-in self-ligating brackets (SLB). Group 2 included 12 patients bonded with 0.022-in conventional brackets (CLB). Cone-beam computed tomography (CBCT) scans and a 3D program (Dolphin) assessed changes in transversal width of buccal bone (TWBB) and buccal bone thickness (BBT) before (T1) and 7 months after treatment onset (T2). Measurements on dental casts were performed using a digital caliper. Differences between and within groups were analyzed by Student's t-test; Pearson correlation coefficient was also calculated. RESULTS: Significant mandibular expansion was observed for both groups; however, no significant differences were found between groups. There was significant decrease in mandibular buccal bone thickness and transversal width of buccal bone in both groups. There was no significant correlation between buccal bone thickness and dental arch expansion. CONCLUSIONS: There were no significant differences between self-ligating brackets and conventional brackets systems regarding mandibular arch expansion and changes in buccal bone thickness or transversal width of buccal bone.

The facial growth of Class III malocclusion worsens with age, in this case, the early orthopedic treatment, providing facial balance, modifying the maxillofacial growth and development. A 7.6-year old boy presented with Class III malocclusion associated with anterior crossbite; the mandible was shifted to the right and the maxilla had a transversal deficiency. Rapid maxillary expansion followed by facemask therapy was performed, to correct the anteroposterior relationship and improve the facial profile. The patient was followed for a 15-year period, after completion of the treatment, and stability was observed. Growing patients should be monitored following their treatment, so as to prevent malocclusion relapse.

This cross-sectional study aimed at assessing the cephalometric characteristics in the elderly, taking into account differences between genders, age ranges, ethnic groups and dental aspects. The sample consisted of 250 elderly subjects of both genders (163 female, mean age: 68 yr.; 87 male: 70.4 yr.). Conventional lateral cephalograms for cephalometric analysis were scanned and analyzed by Dolphin Imaging software 11.5. The statistical treatment of the data evaluated the influence of gender and age range variables (independent ttest), as well as ethnic group, facial profile, and dental characteristics (one-way ANOVA), on cephalometric measurements. A confidence interval of 95% and level of significance of 5% were considered for all the tests performed. The results revealed: 1) The cephalometric measurements evaluated showed significantly lower values for the female gender; 2) a significant decrease in the cephalometric values was observed in relation to the growth pattern, with the advancement of age; 3) significant cephalometric differences were observed between the ethnic groups and the facial profiles; 3) dentulous patients had greater absolute values for all the components evaluated, followed by the individuals with partial dental losses and by those who were edentulous. It may be concluded that the cephalometric alterations observed in this study are inherent to facial maturity, and that they represent specific characteristics regarding each of the variables evaluated. These modifications must be taken into account when planning the treatment for younger patients, to minimize the modifications arising from the natural aging process.

Absence of the maxillary lateral incisor creates an aesthetic problem which can be managed in various ways. The condition requires careful treatment planning and consideration of the options and outcomes following either space closure or prosthetic replacement. Recent developments in restorative dentistry have warranted a re-evaluation of the approach to this clinical situation. Factors relating both to the patient and the teeth, including the presentation of malocclusion and the effect on the occlusion must be considered. The objective of this study was to describe the etiology, prevalence and alternative treatment modalities for dental agenesis and to present a clinical case of agenesis of the maxillary lateral incisors treated by the closure of excessive spaces and canine re-anatomization. A clinical case is presented to illustrate the interdisciplinary approach between orthodontics and restorative dentistry for improved esthetic results. In this report, the treatment of a girl with a Class II malocclusion of molars and canines with missing maxillary lateral incisors and convex facial profile is shown. Treatment was successfully achieved and included the space closure of the areas corresponding to the missing upper lateral incisors, through movement of the canines and the posterior teeth to mesial by fixed appliances as well as the canines transformation in the maxillary lateral incisors. This is a 14-year follow-up case report involving orthodontics and restorative dentistry in which pretreatment, posttreatment, and long-term follow-up records for the patient are presented.

OBJETIVO: comparar a resistência ao atrito entre braquetes autoligáveis e braquetes convencionais, variando o tipo de fio. MÉTODOS: foram usados braquetes incisivos Abzil Kirium Capelozza e Easy Clip. Uma ligadura elastomérica ou um fio ligável de 0,010" foi usado para ligação do fio no braquete Abzil. Três tipos de ligas de fio ortodôntico foram avaliadas: fio de NiTi de 0,016"; fio de NiTi de 0,016" x 0,022"; e fio de aço de 0,019" x 0,025". Dez observações foram feitas para cada combinação "braquete-fio-inclinação". Os braquetes foram montados em um aparelho especial, posicionados a 90° em relação ao fio, e testados em duas inclinações. O teste de atrito foi realizado na máquina universal de ensaios, a 5mm/min e com 10mm de deslocamento. As médias (em MPa) foram submetidas aos testes ANOVA e de Tukey, a 5% de significância. As superfícies dos fios e dos braquetes foram observadas no MEV. RESULTADOS: o braquete com amarrilhos metálicos (16,48 ± 8,31MPa) apresentou médias mais altas que o braquete com ligaduras elastoméricas (4,29 ± 2,16MPa) e o braquete autoligável (1,66 ± 1,57) (p < 0,05), os quais também diferiram entre si (p < 0,05). Quanto ao tipo do fio, o fio de aço de 0,019" x 0,025" (5,67 ± 3,97MPa) apresentou médias mais baixas (p < 0,05) que os fios de NiTi de 0,016" (8,26 ± 10,92MPa) e de 0,016" x 0,022" (8,51 ± 7,95), os quais não diferiram entre si (p > 0,05). Nenhuma diferença estatística (p > 0,05) foi encontrada entre inclinações de zero (7,76 ± 8,46) e cinco (7,19 ± 7,93) graus. Concluão: o atrito foi influenciado pelo tipo de braquete e sistemas de ligaduras. Diferentes aspectos morfológicos foram observados para os braquetes e fios estudados.

OBJECTIVE: To compare the frictional resistance between self-ligating and conventional brackets tied to different types of wire. MATERIAL AND METHODS : Abzil Kirium Capelozza (Pattern I) and Easy Clip (Roth prescription) incisor brackets were used. An elastomeric ligature or a ligating wire 0.10-in was used to ligate the wire to the Abzil bracket. Three types of orthodontic archwire alloys were assessed: 0.016-in NiTi wire, 0.016 x 0.021-in NiTi wire and 0.019 x 0.025-in steel wire. Ten observations were carried out for each bracket-archwire angulation combination. Brackets were mounted in a special appliance, positioned at 90 degrees in relation to the wire and tested in two angulations. Frictional test was performed in a Universal Testing Machine at 5 mm/min and 10 mm of displacement. The means (MPa) were submitted to ANOVA and Tukey's test set at 5% of significance. The surfaces of wires and brackets were observed at SEM. RESULTS: Steel-tied brackets (16.48 ± 8.31) showed higher means of frictional resistance than elastomeric-tied brackets (4.29 ± 2.16 ) and self-ligating brackets (1.66 ± 1.57) (P < 0.05), which also differed from each other (P < 0.05). As for the type of wire, 0.019 x 0.025-in steel wire (5.67 ± 3.97) showed lower means (P < 0.05) than 0.16-in NiTi wire (8.26 ± 10.92) and 0.016 x 0.021-in NiTi wire (8.51 ± 7.95), which did not differ from each other (P > 0.05). No statistical differences (P > 0.05) were found between zero (7.76 ± 8.46) and five-degree (7.19 ± 7.93) angulations. CONCLUSIONS: Friction was influenced not only by the type of bracket, but also by the ligating systems. Different morphological aspects were observed for the brackets and wires studied

Resumo A má oclusão de Classe III esquelética, com sua imprevisibilidade e natureza potencialmente desfavoráveis, caracteriza um padrão de crescimento com duvidoso prognóstico à mecânica ortodôntica, ainda que esta seja realizada precocemente. Durante muito tempo, a Classe III foi considerada sinônimo de prognatismo mandibular, independente das estruturas esqueléticas comprometidas. O crescimento mandibular, determinado essencialmente por fatores genéticos, dificilmente seria controlado pela intervenção ortodôntica precoce. Assim, optava-se por aguardar o crescimento e então realizar a intervenção ortodôntica associada à cirurgia ortognática. A constatação de envolvimento da maxila como etiologia primária na má oclusão de Classe III foi decisiva para a mudança da terapêutica. O crescimento maxilar, de origem intramembranoso, responderia melhor ao tratamento por meio do controle e direcionamento do crescimento, contribuindo para o sucesso da intervenção precoce. Em muitos casos, excelentes resultados são obtidos com a expansão rápida e protração da maxila. O presente trabalho objetiva descrever e discutir o tratamento de uma paciente com má oclusão de Classe III, cujo plano de tratamento consistiu de duas fases: interceptora, realizada com aparelhos ortopédicos mecânicos e corretiva, com aparelho ortodôntico fixo. Os resultados deste caso clínico demonstraram que a má oclusão de Classe III deve ser interceptada o mais precoce possível, com vistas a redirecionar o crescimento. Esta abordagem deve acontecer, especialmente, quando a maxila é o fator etiológico primário ou quando fatores dentários e/ou funcionais estiverem envolvidos na determinação desta má oclusão. O diagnóstico, o plano de tratamento e o prognóstico dependem da idade do paciente, do potencial de crescimento e da severidade da má oclusão. A intervenção precoce, a indicação de aparelhos adequados e a colaboração do paciente constituem fatores determinantes para a obtenção do sucesso desejado.

Skeletal Class III malocclusion, with its unpredictable and unfavorable nature, has been characterized by a growth pattern with doubtful prognosis regarding orthodontic mechanics, even when performed early. For a long time, Class III malocclusion was regarded as a synonym of mandibular prognathism, regardless of the affected skeletal structures. Mandibular growth, essentially determined by genetic factors, could barely be controlled by early orthodontic interventions. Therefore, the treatment choice was to wait for the patient to grow, and then make an orthodontic intervention associated with an orthognathic surgery. Maxillary involvement in the etiology of Class III malocclusion was conclusive to change orthodontic therapeutics. Maxillary intramembranous growth has a better response to orthopedic treatment, based on growth control and redirection, thus contributing for early intervention success. In several cases, excellent results have been achieved with rapid maxillary expansion and protraction. The aim of this study was to describe and discuss the treatment of a patient with Class III malocclusion, whose treatment planning comprised two phases: interceptive (mechanical orthopedic appliances) and comprehensive (fixed orthodontic appliance). The results of this case showed that Class III malocclusion should be intercepted as early as possible to permit growth redirection, mainly when the maxilla is the primary etiologic factor or dental and/or functional factors are involved. Diagnosis, treatment planning and prognosis depend on patient age, growth potential and severity of malocclusion. Early intervention, adequate indication of appliances, and patient compliance are key factors for good outcomes.

Objective: The aim of this study was to compare the reliability of three different methods of cephalometric analysis. Material and Methods: Conventional pretreatment lateral cephalograms and cone beam computed tomography (CBCT) scans from 50 subjects from a radiological clinic were selected in order to test the three methods: manual tracings (MT), digitized lateral cephalograms (DLC), and lateral cephalograms from CBCT (LC-CBCT). The lateral cephalograms were manually analyzed through the Dolphin Imaging 11.0™ software. Twenty measurements were performed under the same conditions, and retraced after a 30-day period. Paired t tests and the Dahlberg formula were used to evaluate the intra-examiner errors. The Pearson's correlation coefficient and one-way analysis of variance (ANOVA) tests were used to compare the differences between the methods. Results: Intra-examiner reliability occurred for all methods for most of the measurements. Only six measurements were different between the methods and an agreement was observed in the analyses among the 3 methods. Conclusions: The results demonstrated that all evaluated methodologies are reliable and valid for scientific research, however, the method used in the lateral cephalograms from the CBCT proved the most reliable.

The aim of this study was to assess the reliability of a method to measure the following upper airway dimensions: total volume (TV), the nasopharyngeal narrowest areas (NNA), and the oropharyngeal narrowest areas (ONA). The sample consisted of 60 cone-beam computed tomography (CBCT) scans, evaluated by two observers twice, using the Dolphin 3D software (Dolphin Imaging & Management solutions, Chatsworth, California, USA), which afforded image reconstruction, and measurement of the aforementioned dimensions. The data was submitted to reliability tests, by the intraclass correlation coefficient (ICC), and the Bland & Altman agreement tests, with their respective confidence intervals (CI) set at 95%. Excellent intra- and interobserver reliability values were found for all variables assessed (TV, NNA and ONA), with ICC values ranging from 0.88 to 0.99. The data demonstrated an agreement between the two assessments of each observer and between the first evaluations of both observers, thus confirming the reliability of this methodology. The results suggest that this methodology can be used in further studies to investigate upper airway dimensions (TV, NNA, and ONA), thereby contributing to the diagnosis of upper airway obstructions.