Effect of silica coating on bond strength between a gold alloy and metal bracket bonded with chemically cured resin / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to evaluate the effects of three different surface conditioning methods on the shear bond strength (SBS) of metal brackets bonded directly to gold alloy with chemically cured resin. METHODS: Two hundred ten type III gold alloy specimens were randomly divided into six groups according to the combination of three different surface conditioning methods (aluminum oxide sandblasting only, application of a metal primer after aluminum oxide sandblasting, silica coating and silanation) and thermocycling (with thermocycling, without thermocycling). After performing surface conditioning of specimens in accordance with each experimental condition, metal brackets were bonded to all specimens using a chemically cured resin. The SBS was measured at the moment of bracket debonding, and the resin remnants on the specimen surface were evaluated using the adhesive remnant index. RESULTS: Application of metal primer after aluminum oxide sandblasting yielded a higher bond strength than that with aluminum oxide sandblasting alone (p < 0.001), and silica coating and silanation yielded a higher bond strength than that with metal primer after aluminum oxide sandblasting (p < 0.001). There was no significant change in SBS after thermocycling in all groups. CONCLUSIONS: With silica coating and silanation, clinically satisfactory bond strength can be attained when metal brackets are directly bonded to gold alloys using a chemically cured resin.

Effects of chemically cured resin and light cured resin on shear bond strength of metal bracket and ceramic bracket / 대한치과교정학회지

This study was designed for comparison of shear bond strengths and failure patterns of four experimental groups which combinated mesh-backed metal brackets and texture based ceramic brackets (Transcend series 2000((TM))) with chemically cured resin (Mono Lok2((TM))) and visible light cured resin (Transbond((TM))). Brackets were bonded on the extracted human bicuspids, after etching them by manufacturer's recommand, and the shear bond strengths were measured on the Instron machine after 24 hrs passed in the 37degrees C water bath. The results were as follows. 1. Ceramic brackets, transcend series 2000((TM)), bonded with MonoLok2((TM)) showed statistically higher shear bond strength than mesh-backed metal brackets bonded with MonoLok2((TM)). 2. There was no significant difference in shear bond strengths between metal and ceramic brackets bonded with Transbond((TM)). 3. Ceramic brackets bonded with both Transbond((TM)) and MonoLok2((TM)) showed primarily fractures bet?ween brackets adhesive interface. 4. Enamel crack was not found in anyone specimen.