Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

Abstract

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.

Emergence of 3D Printed Dosage Forms: Opportunities and Challenges

“…It has established roots in engineering and many non-medical practices, especially in the automobile industries. Recently its applications in medical devices (31,32), implants (33) 3D printing in its essence is repeated and co-ordinated two-dimensional printing. The main focus in this review is on multi-layer 3D printing whilst single layer printing of flat object is considered less relevant.…”

A Lower Temperature FDM 3D Printing for the Manufacture of Patient-Specific Immediate Release Tablets

“…3D printing established roots in various disciplines from arts and engineering to implants and regenerative medicine (1,2). As yet the exploitation of 3D printing for pharmaceutical applications is still at its infancy.…”

The role of 3D printing in anatomy education and surgical training: A narrative review

“…Life-size 3Dp plastic skulls and brains have a material cost of below $15 Naftulin et al, 2015), with a spinal model containing multiple vertebrae and fractures costing $20 (Zhenzhu Li et al, 2015). The costs of printing softer, silicon models can be greater depending on the functionality required, but using 3Dp plastic moulds and injecting medical-grade silicon can reduce the costs involved significantly (Chung et al, 2014;He et al, 2014). This method has been used to produce silicon ear prosthetics for $30, and further savings can be made when moulds can be re-used.…”

“…For soft-tissue replacement, a model of the lesion can be printed and used as a mould for further processing (Chung et al, 2014;He et al, 2014). This has been used to successfully close nasal septal perforations (Onerci Altunay et al, 2016), with an improved retention rate of the implant.…”