OBJETIVO: determinar as características mecânicas de alças em gota e em gota com helicoide, quando da incorporação de variações na liga metálica (aço inoxidável e beta-titânio), na intensidade de dobras de pré-ativação (0º e 40º) e na secção transversal do fio utilizado para a construção dessas alças (0,017" x 0,025" e 0,019" x 0,025"). MÉTODOS: foram submetidas ao ensaio mecânico 80 alças para fechamento de espaços, sendo quantificadas as magnitudes de força horizontal, proporção momento/força e relação carga/deflexão produzidas pelos corpos de prova. As alças foram submetidas a uma ativação total de 5,0mm, sendo registrados os valores a cada 1,0mm de ativação. No tratamento estatístico dos dados obtidos, foi realizada a análise de variância, sendo essa complementada pelo teste de comparações múltiplas de Tukey, considerando o nível de significância de 5%. RESULTADOS: de maneira geral, as alças em gota com helicoide produziram menores magnitudes de força horizontal e relação carga/deflexão e maiores valores de proporção momento/força do que as alças em gota. Dentre todas as variáveis analisadas, aquela que apresentou uma maior influência na força horizontal e na relação carga/deflexão produzidas pelas alças foi a liga metálica. Já a proporção momento/força mostrou ser influenciada em maior grau pela pré-ativação das alças de fechamento de espaços.

OBJECTIVE: To determine the mechanical characteristics of teardrop loop with and without helix fabricated using different metal alloy compositions (stainless steel and beta-titanium), submitted to different intensities of bends preactivation (0º and 40º), and with different cross-sectional dimension of the wire used to build these loops (0.017 x 0.025-in and 0.019 x 0.025-in). METHODS: Eighty loops used to close spaces were submitted to mechanical tests. The magnitudes of horizontal force, the moment/force ratio, and the load/deflection ratio produced by the specimens were quantified. Loops were submitted to a total activation of 5.0 mm and the values were registered for each 1.0 mm of activation. For statistic data analysis, a analysis of variance was performed and a Tukey's Multiple Comparison test was used as supplement, considering a 5% level of significance. RESULTS: In general, teardrop loops with helix produced lower magnitudes of horizontal force and load/deflection ratio, and higher moment/force ratio than teardrop loops without helix. Among all analyzed variables, metal alloy composition presented greater influence in the horizontal force and in the load/deflection ratio. The moment/force ratio showed to be more influenced by the preactivation of loops for space closure.

The aim of this study was to analyze the association between infantile bruxism and the terminal relationships of the primary second molars. A total of 937 pre-school children (both genders), aged from 2 to 6 years, from municipal schools in São Paulo were evaluated. In this study, a questionnaire considering the bruxism habit and the presence of headaches and/or restless sleep was answered by the parents/guardians. A clinical exam of occlusion in the anteroposterior direction (vertical plane - VP, mesial step - MS and distal step - DS) was performed by the examiners in the school environment. Student's t test, Fisher's test and a logistic regression test were applied for the statistical analysis at a significance level of 5%. The prevalence of the bruxism habit was 29.3% among the total sample. Because there was no significant difference between the sides evaluated, the left side was taken as the standard. Among those children with bruxism, 25.7% presented a mesial step terminal relationship at the primary second molars, 29.1% had DS, and 30.2% had VP. Regarding the association of the parafunctional habit with the type of terminal relationship, no significant results were found. Children who slept restlessly or suffered from headaches were verified to show a higher chance of expressing the habit (OR = 2.4 and 1.6, respectively). The prevalence of bruxism in the studied sample was 29.3%, and its association with the primary second molars' terminal relationship was not statistically significant.

OBJETIVO: o presente estudo avaliou as variações da base craniana anterior (S-N), base craniana posterior (S-Ba), e ângulo de deflexão da base do crânio (SNBa) entre três diferentes padrões faciais (Padrão I, II e III). MÉTODOS: selecionou-se uma amostra de 60 telerradiografias em norma lateral de pacientes brasileiros leucodermas, de ambos os sexos, com idades entre 8 anos e 17 anos. A amostra foi dividida em três grupos (Padrão I, II e III), sendo cada grupo constituído de 20 indivíduos. Os critérios de seleção dos indivíduos para cada grupo basearam-se nos valores de ANB, Wits e ângulo do contorno facial (Gl.Sn.Pg'). Para observar se houve diferença nos valores médios de SNBa, S-N e S-Ba entre os diferentes grupos, utilizou-se a Análise de Variância One Way - ANOVA, seguida de testes post-hoc de Scheffé. RESULTADOS E CONCLUSÕES: não houve diferença estatisticamente significativa na deflexão da base do crânio entre os diferentes padrões faciais (Padrão I, II e III). Também não houve diferença significativa nos valores da base anterior e posterior do crânio entre o Padrão I e o Padrão II. Os valores médios de S-Ba apresentaram-se reduzidos no Padrão III, com diferença estatisticamente significativa. Os valores médios de S-N também se apresentaram reduzidos no Padrão III, embora sem diferença estatisticamente significativa. Essa tendência a valores reduzidos da base do crânio poderia explicar a deficiência maxilar e/ou prognatismo mandibular, características que podem estar presentes no Padrão III.

OBJECTIVE: This study evaluated the variations in the anterior cranial base (S-N), posterior cranial base (S-Ba) and deflection of the cranial base (SNBa) among three different facial patterns (Pattern I, II and III). METHOD: A sample of 60 lateral cephalometric radiographs of Brazilian Caucasian patients, both genders, between 8 and 17 years of age was selected. The sample was divided into 3 groups (Pattern I, II and III) of 20 individuals each. The inclusion criteria for each group were the ANB angle, Wits appraisal and the facial profile angle (G'.Sn.Pg'). To compare the mean values obtained from (SNBa, S-N, S-Ba) each group measures, the ANOVA test and Scheffé's Post-Hoc test were applied. RESULTS AND CONCLUSIONS: There was no statistically significant difference for the deflection angle of the cranial base among the different facial patterns (Patterns I, II and III). There was no significant difference for the measures of the anterior and posterior cranial base between the facial Patterns I and II. The mean values for S-Ba were lower in facial Pattern III with statistically significant difference. The mean values of S-N in the facial Pattern III were also reduced, but without showing statistically significant difference. This trend of lower values in the cranial base measurements would explain the maxillary deficiency and/or mandibular prognathism features that characterize the facial Pattern III.

OBJETIVO: avaliar comparativamente a prevalência das características de espaçamento anterior em nipo-brasileiros e leucodermas, na dentição decídua. MÉTODOS: duas amostras de crianças com 2 a 6 anos de idade foram selecionadas: 405 nipo-brasileiros de 36 escolas do estado de São Paulo e 510 leucodermas de 11 instituições públicas da cidade de São Paulo. As variantes oclusais foram classificadas em quatro categorias, nas arcadas superior e inferior: espaçamento generalizado; somente espaços primatas; ausência de espaços; e apinhamento. Foi aplicada regressão logística para análise do efeito dos fatores idade, sexo e grupo étnico sobre a prevalência das características oclusais (α = 0,05). RESULTADOS: em nipo-brasileiros, o espaçamento generalizado foi a característica mais prevalente nas arcadas superior (46,2%) e inferior (53,3%). A frequência dos espaços primatas foi maior na arcada superior (28,2% versus 15,3%). Para a ausência de espaços (21,7-26,4%) e o apinhamento (4,0-4,9%), a variação entre as arcadas foi relativamente pequena. Em leucodermas, a ausência de espaços e a presença exclusiva dos primatas evidenciaram distribuição similar à observada nos nipo-brasileiros. O espaçamento generalizado foi diagnosticado em aproximadamente 50% das arcadas. A prevalência de apinhamento foi maior na arcada inferior (12,8% versus 3,9%). O único modelo de regressão logística que apresentou algum fator significativo foi o ajustado para a prevalência de apinhamento. Apenas o fator racial foi significativo (p < 0,001). CONCLUSÃO: sugere-se que as características de espaçamento anterior, na dentição decídua, não estariam condicionadas à idade ou ao sexo. Contudo, leucodermas teriam chances 2,8 vezes maiores de apresentar apinhamento na arcada inferior, em comparação aos nipo-brasileiros.

OBJECTIVE: To carry out a comparative evaluation of the prevalence of anterior spacing characteristics in Japanese-Brazilian and white children in primary dentition. METHODS: Two selected samples of children aged 2-6 years were: 405 Japanese-Brazilians from 36 schools in the State of São Paulo and 510 white children from 11 public institutions in São Paulo city. The spacing features in the maxillary and mandibular arches were assigned to four categories: generalized spacing; only primate spaces; no spacing; and crowding. Logistic regression was used to analyze the effect of age, gender and ethnic group on the prevalence of the occlusal characteristics (α=0.05). RESULTS: In Japanese-Brazilians, generalized spacing was the most prevalent trait in the maxillary (46.2%) and mandibular (53.3%) arches. The frequency of primate spaces was higher in the maxillary arch (28.2% versus 15.3%). Concerning no spacing (21.7-26.4%) and crowding (4.0-4.9%), the variation between arches was relatively small. In white children, no spacing and exclusive presence of primate spaces showed distributions similar to that observed in Japanese-Brazilians. Generalized spacing was diagnosed in approximately 50% of the arches. Crowding prevalence was higher in the mandibular arch (12.8% versus 3.9%). The regression model adjusted for crowding prevalence was the only significant one. Only racial factor was significant (p<0.001). CONCLUSION: It may be suggested that anterior spacing features in primary dentition would not be influenced by age or gender. Nevertheless, white children would have 2.8 times more chances of presenting crowding in the mandibular arch, in comparison with Japanese-Brazilians.

The aim of this study was to evaluate the shear bond strength of brackets bonded with different restorative systems and compare it with that afforded by an established orthodontic bonding system. Seventy human bicuspids were used, divided into five different groups with 14 teeth each. Whereas a specific orthodontic bonding resin (TransbondTM XT) was used in the control group, the restorative systems Charisma, Tetric Ceram, TPH Spectrum and Z100 were used in the other four groups. Seven days after bonding the brackets to the samples, shear forces were applied under pressure in a universal testing machine. The data collected was evaluated using the ANOVA test and, when a difference was identified, the Tukey test was applied. A 5% level of significance was adopted. The mean results of the shear bond strength tests were as follows: Group 1 (Charisma), 14.98 MPa; Group 2 (Tetric Ceram), 15.16 MPa; Group 3 (TPH), 17.70 MPa; Group 4 (Z100), 13.91 MPa; and Group 5 or control group (TransbondTM XT), 17.15 MPa. No statistically significant difference was found among the groups. It was concluded that all tested resins have sufficient bond strength to be recommended for bonding orthodontic brackets.

OBJETIVO: este artigo tem como objetivo abordar as características do tratamento ortodôntico associado a uma atuação odontogeriátrica, pois devido a um aumento da expectativa de vida, um maior número de pacientes idosos tem procurado tratamento odontológico para uma reabilitação estética e/ou funcional. METODOLOGIA: através de uma avaliação de dados presentes na literatura são abordados fatores como enfermidades sistêmicas, uso de medicamentos, condição da saúde bucal, quantidade de osso alveolar, motivação do paciente e estabilidade oclusal após a terapia ortodôntica. Para exemplificar o tratamento ortodôntico no paciente idoso são apresentados dois casos clínicos. CONCLUSÕES: o tratamento ortodôntico representa uma intervenção viável na atuação odontogeriátrica, desde que realizado com forças suaves, considerando as limitações de cada caso e respeitando as características inerentes a esta atuação.

OBJECTIVE: to approach the characteristics of the orthodontic treatment in aged patients, because the increase of life expectancy resulted in a bigger number of these kind of patients looking for orthodontic treatment. METHODS: an evaluation of the literature show a series of factors as: systemic disease, medicine utilization, condition of the buccal health, amount of alveolar bone, patients’ motivations and occlusal stability after the orthodontic therapy. To demonstrate the orthodontic treatment in the aged patient two clinical cases are presented. CONCLUSIONS: the orthodontic treatment represents a viable intervention in the aged patients, since that carried through with soft forces, considering the limitations of each case and respecting the inherent characteristics to these patients.