Avaliação da resistência adesiva e do padrão de descolagem de diferentes sistemas de colagem de braquetes associados à clorexidina

Abstract

OBJETIVOS: o objetivo deste estudo in vitro foi avaliar a resistência adesiva e o padrão de descolagem de diferentes sistemas de colagem de braquetes (Sistema Transbond XT / 3M-Unitek e Sistema Enlight / Ormco) cujos respectivos adesivos foram pré-misturados ao verniz de clorexidina (Cervitec / Ivoclar-Vivadent). METODOLOGIA: a amostra utilizada foi constituída por 60 pré-molares humanos, extraídos por indicações ortodônticas, incluídos em cilindros de PVC e divididos aleatoriamente em quatro grupos: grupo 1 - Sistema Transbond XT conforme prescrito pelo fabricante; grupo 2 - Sistema Transbond XT associado a verniz de clorexidina; grupo 3 - Sistema Enlight conforme prescrito pelo fabricante; grupo 4 - Sistema Enlight associado a verniz de clorexidina. A resistência adesiva foi avaliada pelo teste de cisalhamento na máquina de ensaios universal EMIC (0,5mm/min); o padrão de descolagem foi avaliado, através da lupa estereoscópica STEMI 2000-C / Zeiss (20x), pela observação do Índice de Adesivo Remanescente (IAR) na superfície do esmalte dentário, após a descolagem dos braquetes. RESULTADOS: não houve diferença estatisticamente significante (p < 0,05) entre os grupos experimentais (grupos 2 e 4) e os respectivos grupos controles (grupos 1 e 3). CONCLUSÕES: a resistência adesiva e o padrão de descolagem não foram alterados pela associação do verniz de clorexidina aos respectivos adesivos dos sistemas de colagem testados.

Avaliação da atividade antimicrobiana de adesivo ortodôntico associado a verniz de clorexidina e timol na colagem de braquetes

“…Similarly to Ribeiro's 23 findings, it appears that given the formation of a zone of inhibition the combination of chlorhexidine varnish and orthodontic bonding material enabled antimicrobial activity by releasing the antimicrobial substance into the culture medium, thereby inhibiting in vitro bacterial growth in areas surrounding the bracket. It is likely that a small amount of chlorhexidine was released from the portion below the bracket since only a thin layer of adhesive associated with varnish was exposed to the culture medium.…”

“…19 Cervitec varnish was used because it is a compound widely used as a source of chlorhexidine in many studies. 1,7,18,23 This study further disclosed the antimicrobial action of chlorhexidine, whose effectiveness is well established in dentistry, 5 where it is associated with bonding resins used in orthodontics. However, further in vitro and in vivo studies are needed to determine the clinical significance and duration of antimicrobial properties on a variety of oral cavity microorganisms involved in the pathogenicity of bacterial biofilms and caries.…”

“…Karaman and Uysal 15 agreed that shear strength becomes clinically acceptable when the varnish has been mixed with the adhesive in a 2:1 ratio, respectively. Ribeiro 23 and Martinez, 18 after evaluating the bond strength of bonding systems whose adhesives had been pre-mixed with Cervitec chlorhexidine varnish, concluded that there was no statistically significant change in bond strength compared with adhesive alone. Further studies are needed to evaluate mechanical strength after the release of chlorhexidine, color stability, local and systemic cell and tissue compatibility, before the use of an adhesive/varnish combination in daily clinical practice is fully warranted.…”

“…In this research, a modified version of the culture technique described by Ribeiro 23 for verification of growth inhibition was used.…”

Evaluation of the anti-cariogenic potential and bond strength to enamel of different fluoridated materials used for bracket bonding

“…Nowadays, the prevention of dental caries is a primary objective in all areas of Dentistry. In Orthodontics, white spot lesions must be avoided, so new materials are being evaluated for this purpose 1,2 .…”