Abstract
The bonding materials used in orthodontics must resist to masticatory and active orthodontic forces. The aim of this study is to evaluate and compare the tensile bond strength of three orthodontic bonding procedures: acid etching and chemically cured macrofilled composite (Evicrol, SpofaDental, Jièin, Cehia), glass ionomer cement Ketac Cem (3M ESPE AG, Seefeld, Germany) and self-etching primer with light cure adhesive bond material (Transbond Plus Self Etching Primer + Transbond Plus Color Changer Adhesive, 3M Unitek, Monrovia, California). Moreover, after removing the brackets, the Adhesive Remnant Index (ARI) has also been measured. For this purpose 30 recently extracted human premolars were used, grouped randomly in three groups, 10 teeth for each tested material. After bonding the brackets, these were torn off from the teeth surfaces with a tensile testing machine (Instron 1195). The ultimate tensile strenght (UTS) and the ARI has been measured. Our conclusion was that glass ionomer cement fails first to the tractioning forces, while light cured composite has proven to resist best to streching and traction. Although light-cured composite has failed to lower forces than the chemically cured one, the frequency of ARI score 3 has been the highest, which means that its adhesion is the best. Key words: tensile bond strength, bonding material, adhesive remnant index