Effect of resin modified glass ionomer adhesive at different temperatures on the shear bond strength of orthodontic brackets

Abstract

Aim: to compare and evaluate the effect of different temperatures of resin modified glass ionomer adhesive on the shear bond strength of orthodontic brackets. Methods: orthodontic brackets were bonded using resin modified glass ionomer cement on extracted premolar at four different temperature (4°C, 20°C, 37°C and 55°C). A universal measuring device was used to assess the shear bond strength with a crosshead speed of 0.5mm/min. Mode of bond failure was assessed using adhesive remnant index. One-way ANOVA, post hoc Tukey tests, and an independent t-test were used to analyse the data. Result: The shear bond strength of resin modified glass ionomer cement when heated at 37°C showed its highest strength and lowest when refrigerated at 4°C (p˂0.001). Conclusion: The bond strength of orthodontic brackets was improved by preheating resin modified glass ionomer cement to body temperature before bonding the brackets.

Keywords: Shear bond strength, Orthodontic brackets, resin modified glass ionomer adhesive, extracted premolars and adhesive remnant index.