This prospective, in vivo study compared bond failure and enamel decalcification with a cyanoacrylate bracket bonding system (SmartBond, Gestenco International, Gothenburg, Sweden) and a traditional light-cured composite system (Light Bond, Reliance Orthodontic Products, Itasca, Ill). A total of 327 teeth were evaluated after a period of 12 to 14 months; 163 experimental teeth were bonded with the cyanoacrylate bonding system, and 164 control teeth were bonded with the light-cured composite resin. All teeth were evaluated for breakage (bond failure). The average percentage of bracket failures with cyanoacrylate was 55.6% compared with 11.3% with composite resin (P