The Best Material for Your Medical Prototypes

The medical industry is the fastest-growing, most innovative, and most rapidly evolving of all the industries that use rapid prototyping and additive manufacturing technology.

Because of sophisticated prototyping and research, experts are introducing improvements in pharmaceuticals, medical product design, prostheses, surgeries, and surgical tools. Because the prototype machinery and parts have direct contact with the human body, particularly living cells, they must be compatible.

 

 

Requirements for materials to be used in the medical industry:

 

Biocompatibility:

Because medical prototypes are in close contact with the human body, they must be innocuous and nonreactive to live tissues. Biocompatible materials are those that are harmless to body cells and can readily be employed for surgical or other medical applications. As a result, certain materials are employed for these prototypes, which should not be poisonous or deplete the human body’s biodiversity.

Studies of many types were carried out to determine the biodiversity of the materials and how they behave when used in the human body. Following are some of the experimental approaches to check the material according to US requirements.

 

Acute Systemic Toxicity (Systemic Injection) Test: This test checks the irritant effect of the body when the material is applied to the skin or inhaled by the patient.

Intracutaneous Test: This test determines the effect of the material when it is implemented on subdermal tissue.

Implantation Test: This test is done to study the intramuscular implementation of the prototype part; this test will be done on some animal samples for five days for a better result.

Serializability: One of the most significant factors to consider when selecting proper material is sterilizability. As a result, your material should be able to withstand high stress and strain ratios, as well as temperature restraint, to withstand sterilization treatments.

Bio Usability: Body part transplant surgeries, such as prosthetics, dentures, implants, and artificial organ implants, require materials that are compatible with human body tissues, hence biocompatibility is insufficient. For prosthetic bones, for example, the material should be resistant and able to withstand specified levels of fatigue.

Best Materials For CNC medical prototypes:

CNC machining is ideal for making medical prototypes because it offers a variety of material options that are both biocompatible and sterilized for human interaction. These materials meet international class 4 grade certification.

  • Acetal (also known as Delrin or POM)
  • Polypropylene (PP)
  • Polyetherimide (PEI)
  • Polyether ether ketone (PEEK)
  • Polysulfone (PSU)
  • Polyphenol sulfone (PPSU)

 

Non-certified plastics are used for earlier stage prototyping or clinical trial stage, They are the same in mechanical and clinical usage, but they are available at a low price tag. Delrin 150 is an excellent material for early-stage prototyping.

 

Sterilizable Materials

Sterilization is required for every material that will be used for human surgery or in any implementation process. Various sterilization procedures exist, including autoclave, pressure sterilization, vacuum sterilization, radiation, and more.

 

Implants (Hip, Spine, Knee implants): Titanium alloys (Ti6Al4V), Cobalt-chrome alloys (CoCr28Mo6), Stainless steel, PEEK (Polyether ether ketone), polyethylene, polyurethane-coated silicone, etc.

Surgical instruments CNC: Ti Alloy (Ti6Al4V), SUS Alloy (SUS630, SUS420J2, SUS440C), Al Alloy (A 2000 series, A 6000 series), Resin (GFRP, CFRP, PEEK)

Artificial Joints Material: Cobalt-Chromium Alloy, Ti Alloy (Ti6Al4V, Ti-15Mo-5Zr-3Al, Ti-6Al-2Nb-1Ta-0.8Mo), Resin (UHMWPE), Ceramics (Zirconia, Alumina)

Screws, catheter reinforcements, and needle cannula: Stainless steel

Pre-sterilized single-use device: PVC

Surgical face mask: non-woven fabric (Polypropylene or PP)

Sensors: piezoelectric ceramics

 

 

Injection Molding Materials for Medical Prototypes:

 

Injection molding Materials for medical prototypes should be durable, Reliable and FDA regularized, The injection molding technique provides excellent tolerance and cost savings for Porotypes while maintaining high consistency and tolerance.

Medical-grade plastics for prototyping should have a greater molecular weight and superior heat resistance and chemical properties, such as high tensile strength to avoid breakage and high-temperature load ratings to avoid deformation during sterilization.

In a conclusion, while selecting a suitable material for injection molding, one should be fully informed of all applicable requirements and certifications.

 

 

Polycarbonate:

Due to its great strength, stress, and heat resistance capabilities, it is a suitable material for medical tubing and procedures. It also has lower moisture absorption than acrylic materials.

PEEK:

It’s an excellent material for medical-grade plastic signs since it’s resistant to cracking and has high-temperature resistance, allowing it to be sanitized in an autoclave. Peek is FDA-approved and UL 94 V-0 certified for food and medical applications.

Ultem™: Ultem is also an ideal biodegradable material due to its high dimensional stability and exhibits superior strength and stiffness. It can also be sterilized through the autoclave.

 

3 D printing Materials for medical prototype:

The use of 3D printing in the medical industry has resulted in numerous innovations and developments. 3D printing techniques allow us to manufacture highly complex and innovative parts and devices such as custom prosthetics and orthodontics, implants, custom anatomical models for surgical preparation, anatomical study models, medical aids, prototypes, medical tools, and general medical equipment.

The following materials are often used for medical 3-D printing because of their durability and lack of toxicity.

 

PA 12 (Nylon)

Nylon is a versatile, lightweight, temperature and chemical-resistant polymer that is often utilized in the manufacture of prosthetics.

Nylon can be sterilized using gas plasma, steam autoclaves, or gamma radiation, and it can be produced using the M

JF or SLS techniques.

 

ABS M30i

ABS M30 I is the most extensively used thermoplastic in the medical business; it is mostly used for aesthetics and medical models. ABS M30 I is extremely compatible with human tissue and can be disinfected with gamma radiation or plasma steam, which is why it is a worldwide certified material.

It also has a high stress-to-weight ratio, is temperature resistant, and has an optimum tensile strength ratio. Engineers and designers in the medical, pharmaceutical and food-packaging industries will find it ideal for creating surgical planning models, medical devices, instruments, and fixtures.

 

Silicone (Sil 30)

Silicone is a suitable heat and tear-resistant elastomer, and it is created using carbon DLS production technology. Silicone is ideal for the creation of medical wearables that come into contact with human skin, as well as respiratory masks.

 

Titanium (Ti6Al4V): 

Titanium is the most common material used in medical orthopaedic implants, particularly for bone and joint procedures. It is exceptionally strong, heat resistant, hard, corrosion-resistant, and non-reactive. It is the most common metal, with high biocompatibility and the ability to be sterilized using a variety of methods.

 

Cobalt chrome (CoCr28Mo6)

Just like Titanium Cobalt is also used in medical implants, it is mostly used for heavy joint and bone surgeries like hip, thesis, and teeth. It also has excellent heat resistance, and fatigue-bearing properties, and can easily be sterilized, it has high strength ratio and it is a lightweight metal. It is manufactured through the Stirling Printing technique.