Comparison of Shear Bond Strength of Different Wire-Composite Combinations for Lingual Retention: An in Vitro Study

Abstract

Context: As lingual bonded retainers are required for long-term retention in the oral cavity, the wire-composite combination of choice may be the determining factor for the success of lingual bonded retainers. Aim: We compared the shear bond strength of different wire-composite combinations used for lingual bonded retainers and identified the combination of choice for lingual retention in terms of the shear bond strength. Materials and Methods: A total of 108 extracted human maxillary premolars in pairs were divided into 6 groups of 9 samples each. Three different types of retainer wires (namely, Respond [Ormco Corp., Orange, CA, USA], Leone Ligature Wire [Leone S.p.a., Firenze, Italy], and SRW™ Stranded Retention Wire [Ortho Classic Inc., USA]) were bonded to the teeth with the composites (G-aenial™ Universal Flo and Tetric N-Flow). The shear bond strength was measured on debonding using universal testing machine INSTRON. Results: The maximum shear bond strength (58.28 N) was observed in group IV (Respond wire with Tetric N-Flow), whereas the minimum (25.28 N) was observed in group VI (SRW™ Stranded Retention Wire with Tetric N-Flow). A highly significant difference was observed when the shear bond strength of group IV was compared with all the other groups. Conclusions: The maximum shear bond strength was observed in the wire-composite combination of Respond dead-soft wire with Tetric N-Flow composite. Therefore, it could be the wire-composite combination of choice for bonded lingual retainer.