Contact force controlled orthoses made of nitinol shape memory alloy wire for the treatment of malformed ears

Malformed ears of neonates can be effectively treated by employing a suitably shaped orthosis Orthoses made of nitinol shape memory alloy wire and a computer-assisted design system to manufacture the orthosis have been developed. By adding the detour part to the shape of the orthosis, contact force between the orthosis and auricle can be relaxed. The results of insertion experiment and simulation using urethane rubber plate and six orthoses with different detour distances showed that the larger the distance, the contact force becomes smaller when the detour distance was more than 16 mm. Also finite element analysis result using auricular model showed that the contact force can be controlled by the detour dis tance. As for the evaluated case, the longer the distance, the contact force becomes smaller when the detour distance was more than 8 mm. The detoured type orthoses were applied to the treatment of cryptotia, and treated effectively within a year.