In vitro comparison of the retention capacity of new aesthetic brackets

Abstract

Tensile bond strength and bond failure location were evaluated in vitro for two types of aesthetic brackets (non-silanated ceramic, polycarbonate) and one stainless steel bracket, using bovine teeth as the substrate and diacrylate resin as the adhesive. The results show that metallic bracket had the highest bond strength (13.21 N) followed by the new plastic bracket (12.01 N), which does not require the use of a primer. The non-silanated ceramic bracket produced the lowest bond strength (8.88 N). Bond failures occurred mainly between bracket and cement, although a small percentage occurred between the enamel-cement interface with the metal and plastic brackets and within the cement for the plastic bracket. With the ceramic bracket all the failures occurred at the bracket-cement interface. This suggests that the problems of enamel lesions produced by this type of bracket may have been eliminated. The results also show that the enamel/adhesive bond is stronger than the adhesive/bracket bond in this in vitro study.

Análise in vitro da resistência ao cisalhamento de braquetes metálicos colados em incisivos bovinos e humanos

“…Neste trabalho os resultados encontrados de x= 12,96 MPa, x= 15,05 MPa e 17,03 MPa, respectivamente para os grupos I (incisivos humanos), II (incisivos permanentes bovinos) e III (incisivos decíduos bovinos) foram superiores aos preconizados, confirmando altos valores de adesão alcançados pelo Concise Ortodôntico. Estes resultados são semelhantes aos de vários autores 6,8,18,19,23,29 e superiores aos de outros 4,14,27 .…”

Comparison of Shear Bond Strength of Orthodontic Metal Brackets Adhered to Composite Restorations Pretreated with Er;Cr:YSGG and CO2 Lasers and Phosphoric Acid

“…This type of debonding is clinically more desirable, because the need to clean the debonded enamel (restoration surfaces) is decreased in this case and, consequently, the risk of damage to the enamel or restoration will be reduced (Sinha, Nanda, Duncanson, & Hosier, 1995). The frequency of this type of debonding in clinical conditions is more, because providing a favorable etching on the tooth surface is more difficult in this case, due to the lack of control of the humidity, temperature, time and patient movements (Fernandez & Canut, 1999).…”

Propiedades Físico-Mecánicas Y Tipo De Falla Adhesiva Del Esmalte Humano Y Bovino

“…18 Sin embargo, el tipo de fuerza utilizado en su estudio fue una fuerza tensional, es decir, se traccionaron los brackets, por lo cual se puede asumir que el bracket al ser traccionado necesita menor fuerza para su desprendimiento.…”

“…17 Así mismo, Fernández y colaboradores encontraron fallas de tipo ARI 2 (más de la mitad del adhesivo permanece en el diente) en dientes bovinos, que correspondió a fallas de tipo RR, con lo que se podría pensar que al ser traccionados los brackets se produce una falla cohesiva del material. 18 De otro lado, Sfrondini y colaboradores en su investigación al utilizar la punta de la cruceta paralela a la base del bracket obtuvieron fuerzas de cizallamiento que hicieron que al desprenderse los brackets en los dientes bovinos, se presentara un tipo de falla ARI 3 (superficie del esmalte cubierta completamente por adhesivo), 14 contrario a lo encontrado en la presente investigación.…”