Introduction: There is a great variety of orthodontic brackets in the Brazilian market, and constantly evaluating them is critical for professionals to know their properties, so as to be able to choose which product best suits their clinical practice. Objectives:To evaluate the bond strength and the adhesive remnant index (ARI) of different brands of metal brackets. Material and Methods:A total of 105 bovine incisors were used, and brackets of different brands were bonded to teeth. Seven different bracket brands were tested (MorelliTM, American OrthodonticsTM, TP OrthodonticsTM, Abzil-3MTM, OrthometricTM, TecnidentTM and UNIDENTM). Twenty-four hours after bonding, shear bond strength test was performed; and after debonding, the ARI was determined by using an optical microscope at a 10-fold increase. Results: Mean shear bond strength values ranged from 3.845 ± 3.997 (MorelliTM) to 9.871 ± 5.106 MPa (TecnidentTM). The majority of the ARI index scores was 0 and 1. Conclusion:Among the evaluated brackets, the one with the lowest mean shear bond strength values was MorelliTM. General evaluation of groups indicated that a greater number of bond failure occurred at the enamel/adhesive interface.

Aim: The aim of this study was to evaluate the influence of acrylic resin immersion in different mouthwashes on hardness, roughness and color. Methods: Specimens of an orthodontic selfcured acrylic resin (Orto Clas ®) were produced and immersed in five mouthwashes: Plax ® Classic (Colgate ®); Plax ® alcohol-free (Colgate ®); Listerine ® (Johnson & Johnson ®); Periogard ® (Colgate ®) and Periogard ® alcohol-free (Colgate ®). Nine different immersion times were studied:

OBJECTIVE: To evaluate the response of elastomeric ligatures in several colors for a 4 mm traction over time. METHODS: Morelli® elastomeric ligatures, were submitted to traction forces using two rods of circular cross section, until a 4 mm distance was reached, matching the approximate diameter of an upper central incisor bracket of the same manufacturer. The ligatures were kept in artificial saliva immersion at 37 ºC. Forces levels were measured immediately (0 h), 2, 4, 6, 8, 10, 12, 24, 48, 72, 96 hours, 1, 2, 3, 4 weeks and results were submitted to two-way repeated-measures ANOVA statistical analysis. RESULTS: The gray samples showed the higher initial values of tensile strength. The lowest values were presented by purple, light pink, green, black and red groups. The greater tensile strength instability was presented by red, black, silver, green and gray groups. The greater tensile strength stability was presented by deep pink, dark blue, blue, purple and light pink groups. CONCLUSION: Elastomeric ligatures do not present stable behavior when suffering traction forces over time and different colors display different behaviors. Deep pink, dark blue, blue, purple and light pink groups, displayed the most stable forces, suggesting that they should be used during the treatment to obtain constant forces

Purpose: To evaluate the influence of peracetic acid immersion on water sorption, solubility and microhardness of heat and self-cured acrylic resins.Methods: Thirty specimens of each type of acrylic resin were produced for sorption, solubility and microhardness evaluation. Sorption and solubility were evaluated based on ISO1567. For the microhardness test, specimens (20.0×5.0×10.0 mm) were made and evaluated under a 100 g load for 15 s. The test groups were submitted to a peracetic acid 0.2% immersion for 10 minutes. Data of sorption and solubility were analyzed by two way ANOVA and, hardness values, by paired t-test.Results: Values of sorption and solubility were in agreement with ISO1567 requirements to both groups and ranged, in μg/mm 3 , for sorption from 22.28 (±4.40) to 24.25 (±3.27), and from 1.09 (±0.16) to 1.29 (±0.10) for solubility. Solubility showed a statistically significant difference between the two types of resin at test group. There was no statistical significant difference at the microhardness values.Conclusion: In this study, immersion in peracetic acid solution 0.2% showed no alterations at acrylic resin properties tested.Peracetic acid could be recommended to replace the conventional agents for the disinfection of acrylic resin devices.Key words: Acrylic resin; denture cleanser; prosthodontics ResumoObjetivo: Avaliar a influência da imersão em ácido peracético sobre a sorção, solubilidade e microdureza de resinas acrílicas termo e autopolimerizada.Metodologia: Trinta corpos de prova de cada resina acrílica foram confeccionados para avaliação da sorção, solubilidade e microdureza. A sorção e a solubilidade foram avaliadas de acordo com a ISO 1567. Para a determinação da microdureza, os corpos de prova (20×5×10 mm) foram confeccionados e avaliados com uma carga de 100 g por 15 s. Os grupos teste foram imersos em ácido peracético 0,2% por 10 minutos. Os dados de sorção e solubilidade foram analisados com ANOVA de duas vias e de dureza por teste t pareado.Resultados: Os valores de sorção e solubilidade ficaram de acordo com as especificações da ISO 1567 para ambos os grupos e no ensaio de sorção variaram entre 22,28 (±4,40) até 24,25 (±3,27), e de 1,09 (±0,16) até 1,29 (±0,10) para solubilidade, em μg/mm 3 . A solubilidade apresentou diferença estatisticamente significativa entre os dois tipos de resina após imersão em ácido peracético. Os valores de microdureza não apresentaram diferença estatisticamente significativa entre os grupos.Conclusão: A imersão em ácido peracético 0,2% não alterou as propriedades avaliadas das resinas acrílicas.