Fabrication of an aesthetic composite orthodontic archwire based on tube-shrinkage

Abstract

Researchers have recognized composite technology as a possible method to develop aesthetic archwire. In other investigations, pultrusion process was commonly used to produce composite archwires. However, the limitation in this process is that only products, which are longitudinally straight with constant cross-sections, can be produced with a rigid die. To produce wires according to the shape of the human dental arch (elliptic), in this study, a new technique based on tube shrinkage was proposed for the fabrication of composite archwires. This technique has a feature to give better resin impregnation into the fiber reinforcement without fiber damage. Moreover, archwires of the desired dental arch for various patients can be provided, without the need for beta-staging. In this study, two prototype composite wires with longitudinally straight portion were fabricated using this technique, namely (a) glass fiber / epoxy and (b) glass fiber / dental resin. Before the clinical assessment of elliptic wires, bending performance of straight composite wires was investigated in the dry and wet states. The results showed that the bending performance of the prototype composite archwires is comparable to that of a clinical Ni-Ti archwire. It was concluded that the suggested fabrication technique may contribute to the production of more practical composite archwires.