Why is 3D printing important in medical device manufacturing?

The first prototyping device entered the market in the 1980s, making large-scale 3D printing feasible. This revolutionised many industries, particularly manufacturing models that were not required or could not be processed in bulk. One such application of 3D printing is in the healthcare industry, where high-end customised devices are always in need. Jasleen Kaur explains the importance of 3D printing in healthcare.

3D printing has been widely used and publicised in the production of medical devices. This is due to the advancements in healthcare that enabled the development of prosthetics, single-use implants, and a wide range of other highly customisable products. With no standard design to follow, the production of these types of devices is demand-based. These products or machines may have fewer components, but their customisation is vast. 

Prosthetics, dental implants, and other medical devices now don’t need to be adjusted via surgery and can be produced for each individual in the correct measurement and size, thanks to 3D printing. Aside from the other mechanical and strength-based advantages, this is also a cost-effective model because the designs can be created with minimal setup, ensuring no waste. 

The role of plastics in 3D printing and current developments 

Traditionally, the materials used to manufacture 3D-printed devices were titanium and stainless steel. It did, however, face numerous challenges, including heavy weight, high cost, and difficulty to manufacture. As a result, they didn’t come across as an ideal choice, particularly in the medical sector, where products must be easy to handle and never cause corrosion. 

Plastics might have an amazing advantage in dental devices because doctors must hold the device for a longer period of time during the procedure. And if heavy materials are used to make the machines, it can easily result in aches and discomfort. The same is true for amputated arms or prosthetic legs; they cannot be too heavy because they will obstruct the free flow of movement. 

To overcome these challenges, the market is embracing emerging plastics such as PEEK, PPSU, and PEI for external use. Fillers with holding properties are being added to the plastic during the manufacturing process. Plastics also serve as lubricants, and fillers are added to improve mechanical properties and performance. The plastics and fillers used have excellent holding properties, allowing the device to retain its shape even after an extended period of use. 

These fillers, however, can introduce contaminants into the plastic manufacturing process. Thus, a very small amount of these fillers needs to be added in order to maintain the quality, hygiene, and performance attributes. Too much addition can cause the material to become brittle rather than providing the necessary strength for which it is added. Additional products or resins are also used to provide special strength or properties that fillers fail to provide. 

All components used in these medical-grade items must be non-carcinogenic and pose no risk to any individual's health. These components can be placed permanently in their bodies or used for temporary needs. This hourly usage of devices can be classified as bands that are critical aspects of manufacturing medical devices using 3D printing, and companies are attempting to obtain regulatory approval for grades that fall into these bands. 

Depending on their level of contact with the human body, these bands can fall under different categories such as 2 days, 7 days, 28 days, and so on. The greater the number of days for any band, the greater its contact ratio with the human body, and as a result, the rules and regulations are more strictly followed before the product can be commercialised. These products can include implants, dressings, bandages, and so on, depending on whether they are intended for long-term or short-term use. 

Prototyping is used by all industry participants to obtain approval from the relevant regulatory body before officially launching their product. These products are subjected to extensive testing to ensure that all safety precautions are taken, and companies continue to work hard to obtain approvals for a higher band. 

It is worth noting that plastics used in other types of manufacturing cannot be used in medical-grade applications. Plastics typically contain high levels of impurities, which is not an acceptable parameter for medical-grade applications. High-performance polymers such as PEEK, PPSU, and PEI are commonly used plastics in medical application manufacturing. 

The market for 3D printing 

When it comes to 3D printing for medical devices, it is critical to consider product safety and usability. Some materials may cause allergies or be prone to corrosion, making them unsuitable for use in the medical industry. Another important consideration is the regulatory aspect. 

SABIC has introduced a number of grades in its additive manufacturing segment, THERMOCOMP AM compounds. This resin family has low deformation and works well under pressure, as well as offering dimensional stability and low thermal expansion. Because of its high heat resistance, ULTEM AMHU1010F is specifically used in healthcare manufacturing and applications. 

Arkema's solutions, such as liquid resins, thermoplastic pellets, and liquid resins, are said to be solving many problems with incredible properties such as chemical resistance, high toughness, impact resistance, high ductility, and heat resistance. 

Victrex is also investigating the potential of PEEK and PAEK in 3D printing for medical applications. The company provides products with lower printing temperatures, stronger parts, mechanical strength, high purity, chemical resistance, and other unique property combinations. 

All of the innovations and new grades that the key players and others are introducing must follow strict rules and regulations and should be medically approved. Plastics, resins, and fibres must be medically approved by regulatory bodies such as the FDA, the European Medicines Agency (EMA), and others as applicable. These regulatory bodies approve prototypes of medical devices made with 3D printing before they are commercialised. These products must obtain the well-known ISO 10993 certificate, which aids in determining the biocompatibility of medical devices. 

In a Nutshell 

Due to the industry's high demand for customisation, the market for 3D printing applications with a focus on the medical industry will expand at a faster rate. Companies across the value chain are collaborating to provide the best applications to their customers with this aspect of the market in mind. It is highly likely that companies will offer better material options that meet various application requirements in the coming years. We can also expect more plastic-to-metal conversion as the industry matures and end customers gain confidence in plastic medical devices.