Comparison of Mean Shear Bond Strength of Light Cure, Self-Cure Composite Resins, Self-Etching and Moisture-Insensitive Primers: An in vitro Study

Abstract

Objectives: This study was aimed to compare the mean shear bond strength of four orthodontic bonding materials used for bonding orthodontic brackets. Self-cure composite adhesive (Reliance orthodontics), light cure composite adhesive (Transbond XT, 3M Unitek), light cure with self-etching primer (SEP), Transbond XT and Transbond Plus, 3M Unitek and light cure with moisture-insensitive primer (MIP) (Transbond XT and Transbond MIP) were used. Materials and methods: One hundred and twenty maxillary premolar teeth were collected and divided into four groups. Thirty separate maxillary premolar brackets were bonded to the teeth for each of the bonding agents. Debonding were carried out by using Instron universal testing machine. Results: Light cure composite adhesive (Transbond XT, 3M Unitek) had the highest shear bond strength followed by light cure and SEP (Transbond Plus and Transbond XT, 3M Unitek) followed by light cure and MIP (Transbond MIP and Transbond XT, 3M Unitek) and the lowest was self-cure composite adhesive (Rely-a-bond, Reliance orthodontics). Conclusion: All the materials had the minimal shear bond strength required for orthodontic bonding as proposed by Reynolds and they can be used clinically.