Resistência ao Cisalhamento de Braquetes Colados com Dois Tipos de Agentes de União e Expostos à Ação de Bebidas Ácidas

Abstract

RESUMO Objetivos: Avaliar a influência de bebidas ácidas na resistência de união de braquetes ortodônticos colados com os agentes resinosos Transbond™ PLUS Color Change (TPCC) e Ortholink™ e quantificar o Índice de Remanescente Adesivo (IRA) após a descolagem do braquete, a fim de constatar qual compósito apresenta maior resistência à tensão cisalhante e o local onde ocorreu a falha adesiva, respectivamente. Materiais e Métodos: Noventa e seis incisivos bovinos tiveram braquetes colados em sua superfície vestibular e foram divididos em dois grupos (n=48), de acordo com o agente de união utilizado: I) TPCC e II)Ortholink. Em seguida, cada grupo foi separado em quatro subgrupos (n=12), de acordo com a substância na qual as amostras seriam imersas: S1) Coca-cola®, S2) Suco de laranja Del Valle®, S3) Gatorade® e S4) saliva artificial (controle). As amostras dos subgrupos S1, S2 e S3 foram submetidas a três ciclos corrosivos diários de 5 minutos, com intervalos de 2 horas, durante 30 dias, sendo sempre recolocadas em saliva artificial até que um novo ciclo fosse iniciado. Ao fim deste período, foram submetidas ao ensaio mecânico de cisalhamento e à avaliação do IRA. Resultados: Não foram encontradas diferenças estatisticamente significantes para as resinas entre si e entre os subgrupos, nos dois parâmetros testados (p>0,05). Conclusão: Não houve influência das substâncias ácidas testadas sobre a força de adesão dos compósitos utilizados, possuindo ambos resistências semelhantes, e que tanto a interface resina/ braquete quanto braquete/dente apresentaram falhas adesivas. DESCRITORESBraquetes Ortodônticos. Resistência ao Cisalhamento. Ortodontia. ABSTRACT Objective:To evaluate the influence of acidic beverageson the bond strength of orthodontic brackets bonded with the resinous agents Transbond ™ PLUS Color Change (TPCC) and Ortholink ™.The Adhesive Remnant Index (ARI) after bracket removal was further quantified, in order to determine which composite has a higher resistance to shear stress and where there was adhesive failure. Material and Methods: Ninety-six bovine incisors had brackets bonded on their vestibular surfaces and were divided into two groups (n = 48), according to the bonding agent used: I) TPCC and II) Ortholink. Then, each group was divided into four subgroups (n = 12) in accordance with the substance inwhich the samples would be immersed: S1) Coca-Cola®, S2) Orange juice Del Valle®, S3) Gatorade® and S4) artificial saliva (control). Samples of subgroups S1, S2 and S3 were subjected to three corrosive cycles daily for 5 minutes with 2 hours intervals for 30 days, each being replaced in artificial saliva until a new cycle was started. At the end of this period, sampleswere subjected to mechanical shear test and the ARI assessment. Results: No statistically significant differences were found betweenthe compositesand between the subgroups for the two parameters tested (P>0.05). Conclusion: There was no influence of acidic beverageson the bond strength of the composites, asboth showedsimilar resistance, an...

Influência Da Modificação Da Base De Colagem E Da Contaminação Salivar Na Resistência De União De Tubos Ortodônticos Colados Ao Esmalte Humano

“…It is known that the ideal adhesive material should have adequate bond strength to the tooth, and during debonding, should be removed without damaging the dental enamel by keeping its initial condition as much as possible (LAMPER et al, 2014). The shear bond strength test is the method of choice to assess the efficacy of orthodontic adhesive systems (RIBEIRO et al, 2008;MELGAÇO et al, 2011;CÂMARA et al, 2017). The scientific literature points out that the minimum value of shear bond strength for clinical use ranges from 5.9 to 7.8 MPa (REYNOLDS, 1975;REYNOLDS;VON FRAUNHOFER, 1977).…”

“…Transbond XT composite, which has been used by the majority of the studies for comparative assessment with other ones, was also used here as an adhesive agent (RIBEIRO et al, 2008;MELGAÇO et al, 2011;BERTOZ et al, 2012). This composite is the gold standard material in several in vitro studies as it has bond strength values ranging from 7 to 19 MPa (RIBEIRO et al, 2008;MELGAÇO et al, 2011;CÂMARA et al, 2017). By comparing the results of the present study with the reference values reported by Reynolds and von Fraunhofer (1977), as well as with previous studies using the same composite and orthodontic tubes modified by welding a metal mesh to their base (RIBEIRO et al, 2008;MELGAÇO et al, 2011;BERTOZ et al, 2012), it was found that the bond strength values were very close to the minimum value set by Reynolds (1975), but lower than to those of more recent studies (RIBEIRO et al, 2008;MELGAÇO et al, 2011;CÂMARA et al, 2017).…”

Experimental composite containing silicon dioxide-coated silver nanoparticles for orthodontic bonding: Antimicrobial activity and shear bond strength

“…31 The SBS test represents the method of choice to evaluate the efficiency of orthodontic bonding systems. 32,33 The scientific literature points out that the minimum value of SBS for clinical use varies between 5.9 and 7.8 MPa. 34 would ideally occur at the adhesive-bracket interface, resulting in a large amount of remaining adhesive bonded to the enamel (score 3) and a lower risk of enamel fracture.…”

“…31 The SBS test represents the method of choice to evaluate the efficiency of orthodontic bonding systems. 32 , 33 The scientific literature points out that the minimum value of SBS for clinical use varies between 5.9 and 7.8 MPa. 34 Despite a very classic reference, this study presents important limitations.…”

Resistência Ao Cisalhamento E Avaliação Da Superfície De Esmalte Após Remoção De Braquetes Cerâmicos Monocristalinos Colados Com Diferentes Adesivos Ortodônticos

“…As resinas compostas tornaram-se o principal material de colagem devido às suas propriedades adesivas e são materiais que promovem uma adequada colagem direta, e em conjunto aos adesivos ortodônticos tem demonstrado maior resistência de união ao cisalhamento na colagem dos acessórios ortodônticos (CÂMARA et al, 2017).…”