Rapid bonding and easy debonding of orthodontic appliances with 4-META/MMA-TBB resin using thermal heating

Abstract

4-Methacryloyloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butylborane (4-META/MMA-TBB) resin is widely used as a direct bonding adhesive for orthodontic appliances because of its strong bonding ability. However, its clinical disadvantages include long setting times and difficult debonding with subsequent residual adhesive left on the enamel surface. To resolve these problems, thermal heating was applied to orthodontic appliances. The setting time was dramatically reduced by thermal heating (160°C for 5 s), with the shear bond strength remaining the same as that stated in the manufacturer's instructions. Debonding of appliances following thermal heating (160°C for 20 s) could be easily performed, decreasing the amount of adhesive left on enamel. These conditions were not accompanied by an increase in the heat pain threshold of pulpal dentin. These results suggest that the use of thermal heating in the bonding/debonding of 4-META/MMA-TBB resin may resolve its clinical weaknesses, making its ease of use similar to light-cured resin.

Development of New Method to Reposition Orthodontic Brackets Without Debonding by Using an Ultrasonic Device: An In Vitro Study

“…This adhesive is thought to be slightly softened by heat at the glass transition temperature (Tg). 8, 9 In this study, utilizing these characteristics, metal brackets bonded to extracted bovine anterior teeth by this orthodontic adhesive were assessed to determine the repositioning time and shear bond strengths before and after the procedure. Furthermore, the thermal effects of the repositioning procedure at the enamel surface and the pulpal cavity of extracted human lower premolars were analyzed to determine the safety of this procedure in vitro study.…”