Light Activation and Thermocycling Methods on the Shear Bond Strength of Brackets Bonded to Porcelain Surfaces

Abstract

The present study was evaluated the effect of different light activation and thermocycling methods on the shear bond strength (SBS) and on the adhesive remnant index (ARI) of metal brackets bonded to feldspathic ceramic. Hundred metal brackets were bonded to 20 porcelain cylinders, divided into four groups (n=25) based on light activation and thermocycling processes. The cylinders were etched with 10% hydrofluoric acid for 60 s and coated with two layers of silane. The brackets were bonded with Transbond XT composite resin. Light activation in Groups 1 and 3 was performed during 3 s using the VALO Ortho Cordless appliance with irradiance 3,200 mW/cm2 and in Groups 2 and 4 for 40 s using Optilight Max appliance with irradiance 1,200 mW/cm². The samples were stored in deionized water at 37°C for 24 h and the samples from Groups 1 and 2 were submitted to the SBS test at a rate of 1 mm/min, whereas the samples from Groups 3 and 4 were submitted to 7,000 thermal cycles (5°/55°C) before to the SBS test. The data were assessed by two-way analysis of variance and by Tukey’s test (a=0.05). No significant difference was observed between SBS means in the different light activation devices used. The samples subjected to thermocycling revealed lower SBS values (p≤0.05). There was predominance of score 0 for ARI in all groups. Therefore, the different light activation methods did not interfere in SBS, but thermocycling reduced SBS.

Orthodontic Attachment Adhesion to Ceramic Surfaces

“…78 When comparing VALO Ortho Cordless appliance with irradiance 3200 mW/cm2 for 3 s and Optilight Max appliance with irradiance 1200 mW/cm2 for 40 s, researchers found no significant difference in SBS. 79…”

What Is the Most Effective Technique for Bonding Brackets on Ceramic—A Systematic Review and Meta-Analysis

“…This can be attributed not only to evergrowing aesthetic concerns [ 2 ] but also to the expeditious evolution of orthodontic techniques [ 1 ]. In this age group, there is a high likelihood that an orthodontist will encounter complex restorative treatments using ceramic structures [ 1 , 2 , 3 ] due to their numerous advantages, namely biocompatibility, excellent aesthetics, reduced bacterial plaque accumulation, low thermal expansion, resistance to abrasion or fracture along with colour stability [ 4 , 5 , 6 , 7 ]. The most used ceramic used in dental practices are feldsphatic, lithium and zirconia [ 4 , 8 ].…”

“…This is evident in the clinical practice as well with some studies having reported bracket adhesion failure rates on ceramic surfaces of around 9.8% after two years [ 7 ]. Consequently, orthodontists may encounter difficulties in achieving an optimal adhesion force on ceramic surfaces that is not only effective but also harmless [ 3 , 7 ], that is, an adhesion force that is resistant to orthodontic and masticatory forces while also retaining the function and aesthetics that are provided by this type of restoration after bracket debonding [ 3 , 7 , 10 , 11 ]. Recurrent bracket debonding reduces the success of orthodontic treatment, as it creates adverse consequences in terms of appliance efficiency, cost, treatment duration and patient’s comfort which can all be avoided by achieving adequate adhesion [ 4 , 10 , 12 ].…”

Mastite Bovina E Avaliação Da Qualidade Do Leite Cru Em Laticínio De Minas Gerais

“…O adesivo autocondicionante Xeno IV foi eficaz na união do bráquete ao substrato. Lopes et al (2020), avaliaram o efeito de diferentes métodos de fotoativação e ciclagem térmica na resistência da união ao cisalhamento (RUC) e no índice de remanescente adesivo (IRA) de bráquetes metálicos colados à cerâmica feldspática. Cem bráquetes metálicos foram colados em 20 cilindros de porcelana, divididos em 4 grupos (n = 25) de acordo com o processo de fotoativação e ciclagem térmica.…”