Evaluation of bracket failure in relation to different factors in patients experiencing comprehensive orthodontic treatment: a retrospective cohort study / Evaluación de la falla del bracket en relación con diferentes factores en pacientes que reciben tratamiento ortodóntico integral: un estudio de cohorte retrospectivo

Objective: The aim of this study was to investigate loose brackets in relation to various related factors in orthodontic patients who had completed orthodontic treatment. Material and Methods: In this retrospective study, 738 medical records of patients who had undergone comprehensive orthodontic treatment and matched specific inclusion criteria were selected. Paired t-tests and ANOVA, along with the Mann-Whitney test and Kruskal­Wallis analyses were performed to compare the means of variables between selected subgroups. Results: Loose brackets were found most frequently on premolars, followed by incisors and then canines (p<0.01). Male and young patients were found to have a higher incidence of loose brackets compared to female and adult patients (p=0.044 and p<0.01, respectively). The highest correlation coefficient value was found between treatment duration and total number of loose brackets (0.393), which was statistically significant. Conclusions: The frequency of total number of loose brackets increased with younger age group. Premolar teeth were found to be the most commonly affected teeth, followed by incisors and canines. Mandibular teeth presented more loose brackets than maxillary.

Objetivo: Fue investigar brackets sueltos en relación con varios factores relacionados en pacientes ortodónticos que habían completado el tratamiento de ortodoncia. Material y Métodos: En este estudio retrospectivo, se seleccionaron 738 registros médicos de pacientes que se habían sometido a un tratamiento ortodóntico integral y criterios de inclusión específicos coincidentes. Se realizaron pruebas t pareadas y ANOVA, junto con la prueba de Mann-Whitney y los análisis de Kruskal-Wallis para comparar las medias de las variables entre los subgrupos seleccionados. Resultados: Se encontraron corchetes sueltos con mayor frecuencia en los premolares, seguidos de incisivos y luego caninos (p<0.01). Se encontró que los pacientes masculinos y jóvenes tenían una mayor incidencia de corchetes sueltos en comparación con los pacientes femeninos y adultos (p=0.044 y p<0.01, respectivamente). El valor del coeficiente de correlación más alto se encontró entre la duración del tratamiento y el número total de corchetes sueltos (0.393), que fue estadísticamente significativo. Conclusiones: La frecuencia del número total de corchetes sueltos aumentó con el grupo de edad más joven. Los dientes premolares fueron los dientes más afectados, seguidos de los incisivos y los caninos. Los dientes mandibulares presentan más brackets sueltos que los maxilares.

Efeito de diferentes sistemas de obturação na resistência à fratura de raízes tratadas endodonticamente / The Influence of different obturation systems on the fracture resistance of endodontically treated roots

Objective: This study aimed to compare the fracture resistance of endodontically treated roots filled by different obturation systems. Material and methods: Ninety-six maxillary central incisors were used and decoronated, retaining 12 mm of the roots. On the basis of obturation systems, the roots were randomly divided into 4 groups (n=24): Group1 (COGR): control group (unprepared, unfilled), Group 2 (AVGR): ActiV GP points/ActiV GP sealer, Group 3 (GPGR): Gutta percha points / AH plus sealer, and Group4 (GAGR): Gutta percha points/ActiV GP sealer. The last three groups were obturated with the single cone technique. The roots were then stored in 100% relative humidity at 37 °C for 2 weeks. A vertical compressive force was exerted in a universal testing machine until fracture occurred. Data were statistically analyzed using one-way ANOVA. Results: Mean (SD) failure loads for groups ranged from 920.51 ± 210.37 to 1113.44 ± 489.42 N. The fracture resistance between the different study groups indicated no statistical difference (p>0.05). Conclusions: ActiV GP system did not exert a significant effect on the fracture resistance of endodontically treated teeth.(AU)

Objective: Comparar a resistência à fratura de raízes tratadas endodonticamente obturadas através de diferentes sistemas. Materiais e Métodos: Noventa e seis incisivos centrais superiores foram utilizados, tiveram as coroas removidas, restando 12 mm de raíz. De acordo com o sistema de obturação, as raízes foram divididas em 4 grupos (n=24): Grupo1 (COGR): grupo controle (sem preparo, sem preenchimento), Grupo2 (AVGR): cones ActiV GP / cimento ActiV GP, Grupo3 (GPGR): cones de guta percha / cimento AH plus, e Grupo4 (GAGR): cones de guta percha / cimento ActiV GP. Os últimos três grupos foram obturados através da técnica de cone único. As raízes foram armazenadas em 100% de umidade relativa a 37 °C durante 2 semanas. Uma força compressiva vertical foi aplicada através de uma máquina de ensaio universal até ocorrer fratura. Os dados foram analisados estatisticamente através de ANOVA ­ 1 fator. Resultados: A carga média (SD) obtida no momento da falha variou entre 920.51 ± 210.37 até 1113.44 ± 489.42 N. A resistência à fratura entre os diferentes grupos estudados não indicaram diferença estatística. Conclusão: O sistema ActiV GP não exerceu um efeito significante na resistência à fratura em dentes tratados endodonticamente.(AU)