The role of sandblasting on the retention of metallic brackets applied with glass ionomer cement.

A laboratory investigation of the shear bond strength of stainless steel brackets applied with glass ionomer cement (Ketac-Cem) and a conventional adhesive (Right-on) is described. Sandblasting of the bracket base was undertaken in half of the sample bonded with Ketac-Cem and produced a significant reduction in the probability of failure relative to the unsandblasted sample. Brackets with sandblasted and unsandblasted bases, bonded with Ketac-Cem were subjected to mechanical fatigue in a ball mill for a total of 20 hours. Mean survival time (MST) was then calculated for each group and was found to be significantly improved by sandblasting of the bracket base (P < 0.01).