Technical Considerations for Additive Manufactured Medical Devices

What You Need to Know? 👇

What are the key technical considerations for additive manufactured medical devices according to FDA guidance?

The FDA guidance outlines considerations across design, manufacturing, and testing phases including material controls, software workflow validation, process validation, dimensional measurements, mechanical testing, biocompatibility assessment, and proper removal of manufacturing residues from complex geometries.

How does the FDA approach process validation for 3D printed medical devices?

Process validation must ensure device quality across build cycles and machines where results cannot be fully verified by inspection. This includes in-process monitoring of parameters like temperature, melt pool data, environmental conditions, and validation of test coupons representative of final devices.

What specific testing requirements apply to patient-matched additive manufactured devices?

Patient-matched devices require validation of imaging accuracy, design manipulation software, file conversion integrity, cybersecurity measures for protected health information, and consideration of anatomical changes over time. Each device must be marked with patient identifier and design iteration.

How should manufacturers handle material reuse in additive manufacturing processes?

Material reuse protocols must be documented including filtering processes, limits on reused material percentage, and monitoring for chemistry changes. Evidence must demonstrate that reuse doesn’t adversely affect final device properties through studies comparing virgin versus reused material outcomes.

What are the FDA’s expectations for cleaning and sterilization of complex AM geometries?

Complex geometries like porous structures and internal channels require validation of manufacturing residue removal under worst-case conditions. Destructive testing may be necessary to validate cleaning of trapped volumes, and sterilization validation must account for increased surface area and tortuous pathways.

When is revalidation required for additive manufacturing processes?

Revalidation triggers include software changes, material supplier changes, build volume spacing modifications, software workflow alterations, machine relocation, and post-processing parameter changes. Risk assessment determines if changes require full revalidation based on potential impact on device safety and effectiveness.

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What You Need to Do 👇

Recommended Actions

1. Establish comprehensive documentation of AM process workflow from design to final device
2. Implement process validation protocols considering build orientation and location effects
3. Develop quality control procedures for material controls and post-processing
4. Validate cleaning and sterilization processes for complex geometries
5. Create specific protocols for patient-matched devices including design controls
6. Establish software validation procedures for entire digital workflow
7. Implement material characterization and testing protocols
8. Develop acceptance criteria and testing methods for AM devices
9. Create labeling procedures specific to AM devices
10. Establish revalidation triggers and procedures for process changes

Key Considerations

Non-clinical testing

• Mechanical testing should be conducted on final finished devices after all post-processing
• Consider worst-case combinations of dimensions and features
• Account for build orientation and location effects on properties
• Perform dimensional measurements on samples from multiple build cycles
• Validate process parameters and controls

Software

• Validate software workflow and file format conversions
• Implement internal checks in design manipulation software
• Maintain data integrity throughout file conversions
• Consider cybersecurity for patient-matched devices
• Document build preparation software parameters

Cybersecurity

• Implement proper management of personally identifiable information (PII)
• Protect patient health information (PHI)
• Follow FDA cybersecurity guidance for interactive patient matching workflows

Labeling

• Include patient identifier for patient-matched devices
• Specify intended use
• Indicate final design iteration/version
• Include expiration date based on imaging/design date
• Add precaution about checking for anatomical changes
• Provide reprocessing instructions if applicable

Biocompatibility

• Evaluate biocompatibility of final finished device per ISO 10993-1
• Consider additional testing if using chemical additives with known toxicities
• Assess material chemistry changes during manufacturing

Safety

• Validate cleaning processes to remove manufacturing residues
• Validate sterilization processes considering complex geometries
• Document material reuse protocols and effects
• Implement process controls and monitoring
• Establish acceptance criteria

Other considerations

• Document material specifications and controls
• Validate post-processing steps
• Consider build orientation and location effects
• Implement quality data tracking
• Validate process for patient-matched devices

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Relevant Guidances 🔗

• Use of ISO 10993-1 for Biological Evaluation and Testing of Medical Devices
• Content of Premarket Submissions for Device Software Functions
• Cybersecurity in Medical Devices: Design, Implementation, and Premarket Submissions
• Reprocessing Instructions for Reusable Medical Devices and Non-Sterile Single-Use Devices - Development and Validation

Related references and norms 📂

• ISO/ASTM 52900: Additive manufacturing — General principles — Terminology
• ISO 14971: Medical devices - Applications of risk management to medical devices
• ISO 10993-1: Biological evaluation of medical devices
• ASTM F3122: Standard Guide for Evaluating Mechanical Properties of Metal Materials Made via Additive Manufacturing Processes
• ISO/ASTM 52915: Standard specification for additive manufacturing file format (AMF)

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Original guidance

• Technical Considerations for Additive Manufactured Medical Devices
• HTML / PDF
• Issue date: 2017-12-05
• Last changed date: 2020-03-02
• Status: FINAL
• Official FDA topics: Biotechnology, Orthopedic, Medical Devices, Premarket Approval (PMA), Tissue, 510(k), Premarket, Biologics, HUD/HDE, Investigational Device Exemption (IDE)
• ReguVirta ID: 0eb6b0a5309e98b1d2bed015af6c0444