Investigation of future 3D printed brace design parameters: evaluation of mechanical properties and prototype outcomes

Aim: Spinal brace wear time affects treatment effectiveness of adolescent idiopathic scoliosis but remains challenging with the brace’s bulkiness. This study aims to determine the appropriate material and thickness to improve wear comfort. Materials & methods: Thirty-one specimens were tested with 13 ULTEM1010 and 13 Nylon12 potential materials and 5 standard polypropylene material in 2.5, 3.25 and 4 mm thicknesses to evaluate mechanical properties. Donning tests of ULTEM1010 and Nylon12 printed braces were conducted. Results: Nylon12 with 2.5–3.25 mm thickness had higher flexibility and the closest mechanical characteristics as 4-mm thick polypropylene. ULTEM1010 brace fractured after 615-times and Nylon12 brace handled 2920-times of opening and closing. Conclusion: Nylon12, 2.5–3.25 mm are appropriate design parameters. Further clinical study can validate long term brace effectiveness.