Application of shape memory polyurethane in orthodontic.
A shape memory polymer wire for orthodontic application was prepared by melt-spinning of polyurethane block copolymer (PU) which was synthesized in a two-step process from a reaction of 4,4'-methylene bis(phenylisocyanate), poly(ε-caprolactone)diol (PCL), and 1,4-butanediol. An orthodontic test using the PU wire was carried out in an orthodontic model with a metal bracket. High shape recovery force of 70 gf for PU wire at 40 wt% hard segment content could be preserved for even 1 month after a shape recovery force test at a constant temperature of 50°C. The shape recovery force decreased exponentially during the initial 2 h, but reached an equilibrium shape recovery force of 50 gf after about 20 days. It was found that this shape recovery force was sufficient to correct misaligned teeth in the orthodontic test. The shape memory PU wire possesses strong potential as a novel orthodontic appliance with esthetically appealing appearance.
Jung
Yong Chae
YC
Department of Textile Engineering, Konkuk University, Seoul, Korea.
Cho
Jae Whan
JW
D003764:Dental Materials / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D008310:Malocclusion / Q000628:therapy; D008422:Materials Testing; D016382:Orthodontic Appliance Design; D009969:Orthodontic Wires; D011140:Polyurethanes / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013314:Stress, Mechanical
D003764:Dental Materials; D011140:Polyurethanes