Effect of two-step and one-step surface conditioning of glass ceramic on adhesion strength of orthodontic bracket and effect of thermo-cycling on adhesion strength

Bond strength of metal brackets to feldspathic ceramic treated with different surface conditioning methods: an in vitro study

“…Together with the trimethoxpropyl methacrylate incorporated in its primer for silanization, it is possible that the anticipated effect of weak acid was overcome. This finding of our also agrees with Lyann et al 's study (26) who reported comparable and occasionally higher values using MEP between FC restorations and composites, unlike Asiry et al 's study (18). SEM images of Group 2 demonstrated less roughness and shallower etching pattern than HF group with erosions and randomly appearing superficial and shallow pits which could, again be associated with ammonium polyfluoride which is incorporated in the MEP having a milder acidity but still causing dissolution of the glass phase from the ceramic material.…”

“…The mean SBS values acquired with air-abrasion was followed by values obtained using MEP application. Although treatment with MEP was expected to provide lower SBS values compared to HF treatment due its lower acidic concentration (18), the opposite was true for the current study. MEP contains polyflouoride for etching, and it has been indicated that the bond between silica and fluoride is extremely strong (25).…”

Orthodontic Bonding: Review of the Literature

“…Perhaps, the surface area is not the main mechanical factor affecting bond strength, but rather surface architecture. Asiry et al expressed the importance of exposing the hydroxyl ions within the ceramic surface, which are necessary for chemical bonding to the silane coupling agent [86]. Perhaps, the adequacy of conditioning methods relies on the said method's ability to expose the hydroxyl ions.…”

“…However, a large number of studies showed that AA using 30 μm aluminium oxide with silane coupling and tribochemical coating (CoJet-Sand, 3M ESPE, Seefeld, Germany) produced very strong bonds for brackets to ceramic surfaces [54,76,77,79,80,84]. [85][86][87][88]. It is a one-step conditioning agent that combines ammonium polyfluoride to etch ceramic surfaces along with silane.…”

“…It is a one-step conditioning agent that combines ammonium polyfluoride to etch ceramic surfaces along with silane. It was found to achieve bond strengths that are lower than conventional etching with HF and silane, but still clinically acceptable [85][86][87][88]. Even though it is a perfectly feasible option for prosthodontic use, it is highly questionable whether it should be used for orthodontic bonding of brackets, since it has been contraindicated for intraoral use by the manufacturer due to its toxicity.…”