Aim: To evaluate the effects of three adhesion boosters—All-Bond 2, Enhance LC, and Ortho Solo—on the shear bond strength of new and rebonded (previously debonded) brackets. Methods: One hundred new and 100 sandblasted debonded brackets were bonded to 200 extracted human premolars and divided into eight groups. Results: The new brackets/Ortho Solo group yielded the highest bond strength, followed by the new brackets/All-Bond 2 and the new brackets/Enhance LC groups. During rebonding, Ortho Solo improved the bond strength significantly; however, All-Bond 2 and Enhance LC did not. Conclusion: (1) Bond strength is significantly improved when new brackets are bonded with an adhesion booster; (2) without any adhesion booster, sandblasted rebonded brackets yield a significantly lower bond strength than new brackets; (3) Enhance LC failed to improve the bond strength of rebonded brackets; (4) Ortho Solo increased the bond strength of rebonded brackets significantly; and (5) brackets rebonded with Ortho Solo yielded comparable bond strength as new brackets without any adhesion booster. World J Orthod 2010;11:123–128.