Clinical and laboratory evaluation of metallic brackets bonded with orthodontic composites / Avaliação clinica e laboratorial da colagem de braquetes metalicos com compositos ortodonticos
AUTOR(ES)
Fabio Lourenço Romano
DATA DE PUBLICAÇÃO
2009
RESUMO
The aim of this study was to assess clinically and laboratory the bracket failure rate and shear bond strength of metallic brackets bonded with orthodontic composites. The in vivo study consisted of 20 patients aged between 10.5 to 15.1 years old who had sought corrective orthodontic treatment. Brackets were bonded of the second premolar - second premolar to their upper and lower arches using the adhesive systems: Orthodontic Concise, conventional Transbond XT, Transbond XT without primer, and Transbond XT applied to enamel etched with Transbond Plus Self-etching Primer (TPSEP). All the adhesive systems were used in all patients on a quadrant-rotation basis by repeating the same bonding sequence in every 5 patients. Initial archwires were inserted a week after the brackets bonding. The patients were evaluated during six months in order to quantify the number of brackets failure regarding each adhesive system. At the end of the observation period, 8 brackets failure rates were observed for Orthodontic Concise, 2 for conventional Transbond XT, 9 for Transbond XT without primer, and 1 with Transbond XT + TPSEP. By using the Kaplan-Meier methods, statistically significant differences were found between the materials (p=.0198), and the Logrank test identified these differences. It was observed that conventional Transbond XT and Transbond XT + TPSEP were statistically superior (fewer debonded brackets) compared to Orthodontic Concise and Transbond XT without primer (P<.05). However, no statistically significant differences were found between conventional Transbond XT and TPSEP + Transbond XT as well as between Orthodontic Concise and Transbond XT without primer (P>.05). The in vitro study aimed at assessing the shear bond strength of metallic brackets bonded to different enamel surfaces using the Transbond Plus Color Change composite (TPCC, 3M Unitek) as well as to analyse the Adhesive Remnant Index (ARI). Seventy-two human premolars were used for study, with all samples being divided into six groups (n =12). In Group 1 (control), Transbond XT composite was conventionally used. In other groups (2-6), TPCC was used under the following enamel conditions: phosphoric acid and XT primer; TPSEP; phosphoric acid only; phosphoric acid, XT primer and saliva; and TPSEP and saliva, respectively. After bracket bonding and photo-activation, the samples were stored in distilled water for 24 hours at 37°C in a stove. Next, the brackets were debonded by using an Instron machine at crosshead speed of 0.5 mm/min, and the ARI were evaluated by using a stereoscopic magnifying glass. The mean shear strength values (MPa) were the following: Group 1, 24.6; Group 2, 18.7; Group 3, 17.5; Group 4, 19.7; Group 5, 17.5; and Group 6, 14.8. Data were submitted to both ANOVA and Tukey s test (5%). Group 1 was found to be statistically superior to Groups 3, 5, and 6 (P<.05), with no statistically significant difference compared to Groups 2 and 4 (P>.05). No statistically significant differences were found between Groups 2, 3, 4, 5 and 6 (P>.05). The bracket bonding using TPCC composite showed values comparable to the conventional Transbond XT, and the type of enamel preparation had no influence
ASSUNTO(S)
resinas compostas resistencia ao cisalhamento orthodontics ortodontia composite resins braquetes ortodonticos shear strenght orthodontic brackets
ACESSO AO ARTIGO
http://libdigi.unicamp.br/document/?code=000448096Documentos Relacionados
- Clinical evaluation of the failure rate of metallic brackets bonded with orthodontic composites
- Evaluation of dental enamel before and after fixing and removal of orthodontic brackets ortodônticos
- Avaliação do uso do Self Etching Primer na colagem de braquetes ortodônticos metálicos
- Avaliação da resistência ao Cisalhamento de braquetes novos recolocados com diferentes resinas ortodônticas
- In vitro shear bond strenght evaluation of lingual brackets bonding with different resin thicknesses.