Dear colleagues and friends,
Additive manufacturing (AM) has become a common technology in many departments, although regulations for its use in healthcare facilities may sometimes not be as clear as we would like. Last year, upon my arrival at the European Face Centre (EFC), Professor Maurice Mommaerts and I considered AM an interesting field for research because of many doubts surrounding its products. Mrs. An Vijverman, a lawyer who specializes in Belgian and European life sciences legislation, shared with us her valuable professional opinion regarding the European Union (EU) and Belgian laws related to medical devices. We hope that an interesting peer-reviewed manuscript with a detailed discussion will soon be accepted for publication, though I would like to share a summary of our conclusions here.
Additive manufacturing or three-dimensional (3D) printing, includes techniques used to (re)produce an object from a data set typically in Standard Tessellation Language, allowing us to shift from conventional subtractive- (milling, turning, cutting) or net shaping- (casting, molding, forging, stamping) based manufacturing. Mr. Charles Hull obtained the first approved AM patent in 1986, and in 1989, Stratasys developed the fused deposit filament molding (FDM) printer, now likely the most commonly used type of desktop 3D printer. Other types of AM printers (per the American Society for Testing and Materials) are Stereolithography, Material Jetting, Binder Jetting, Directed Energy Deposition, Powder Bed Fusion and Sheet Lamination that can use various materials, such as paper, wood, polymers, or metals.
The EFC runs two FDM printers (MakerBot Replicator 2 and MakerBot Replicator 2X), which provide up to 0.100-mm layer resolution and 7,522 cm3 (25.2 cm L × 19.9 cm W × 15.0 cm H) of building volume using 1.75-mm diameter polylactic acid (PLA) filaments for consistent and environmentally friendly (biodegradable) printing. Such printers should be in a ventilated area to avoid accumulation of toxic fumes released from melted PLA. If the printed product will be in direct contact with a patient, it should comply with the Medical Device Regulations document first published by the EU Council in 1993 (Directive 93/42/EEC) and its latest amendment released in 2016.
Broadly defined, a medical device (MD)
is an instrument (hardware and software) used for diagnosis, prevention, monitoring, prediction, prognosis, treatment, or alleviation of disease. A custom-made device (CMD)
is “any device specifically made in accordance with a written prescription of a doctor of medicine, of a dental practitioner or of any other person authorized by national law by virtue of this person’s professional qualifications which gives, under his responsibility, specific design characteristics, and is intended for the sole use of a particular patient exclusively to meet their individual conditions and needs.” (Directive 93/42/EEC, 2016)
Once a product is determined to be an MD or CMD, the device is classified into one of three categories outlined by Directive 93/42/EEC (2016)
based on the product’s type and length of body contact. These categories are summarized in Table 1. If the product will not touch a patient (e.g., models used for mock surgery), it is not considered an MD.
Table 1. Medical device (MD) classification criteria according to Annex VII of Directive 93/42/EEC, 2016.
Directive 93/42/EEC (2016) includes over 16 annexes that address MD-related issues, such as essential requirements for patient health and safety depending on the MD’s category, materials involved, packaging (sterile or non-sterile), labeling, and waste disposal procedures. Custom-made devices should have a unique identification number with manufacturer details, the doctor’s name with professional qualifications, the patient’s name, and the purpose of the device. This information should be available for 10-15 years if the product is implantable. Biocompatibility is of key importance. The International Standard Organization (ISO) establishes guidelines with which any MD that is meant to be in contact with a patient must comply (ISO 10993-1; 2009). The standards describe the structured biological evaluation of such an MD that must be planned, carried out, and documented by an experienced professional.
- Models for teaching purposes, studying complex bony structures, performing a mock surgery, for molding a plate or an orbital floor mesh require no special oversight because they will have no direct contact with a patient.
- Custom-made devices that will be in direct contact with a patient, including surgical guides, orthognathic wafers, and facial implants, are classified according to EU Council Directive 93/42/EEC (Table 1) and must adhere to standards described in ISO 10993-1.
Although PLA is widely used in surgeries, FDM printer filaments are not ISO- certified, likely because the material is too porous and its low melting point for conventional sterilization will not guarantee its dimensional stability. Other thermoplastics used for CMD construction, such as acrylonitrile butadiene styrene from Stratasys and polyethylene terephthalate (PET or PETE) and nylon 680 from Taulman 3D, have been granted Class IIa status under ISO 10993. Thus, under specific circumstances, CMDs composed of these materials can be in contact with the patient for up to 30 days. The sterilization process is generally achieved through flash steam or ethylene oxide, depending on the specific product.
If one is manufacturing a CMD within the European Community (CE), one must be aware that:
– CE marking cannot be placed on the CMD unless it is intended for clinical investigation (Articles 17 and 18 of Directive 93/42/EEC, 2016).
– A CMD can be marketed if it complies with Article 42 and Annex XI of Directive 93/42/EEC (2016)
, which describe a conformity assessment procedure addressing general safety and performance requirements outlined in Annex I and related text. Article 4 of the directive specifies that if the product was manufactured within a health institution, the product shall be considered “in service” and must, therefore, comply with CE regulations. However, an exception to the former rule is outlined in Article 4.4a. If the device is kept at the institution, its manufacture passes appropriate quality management procedures, and the health institution provides information upon request regarding its use to their competent authority, including detailed information about the device and its production, then the device does not need to comply with CE regulations. A device produced in-house is not considered “on the market” if the product is not sold to a third party or to a patient; one such case includes surgical guides and models. Nevertheless, the local regulations in each country should be verified. For example, Belgium institutes a more flexible policy (Koninklijk Besluit van 18 Maart 1999 betreffende de medische hulpmiddelen) under which no clearance from the EU Council is needed for CMDs.Proper standardized regulations for AM are needed. Future changes to Directive 93/42/EEC regarding MDs are likely imminent.
Please comment how you print, sterilize, and market AM devices in your countries!
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