Biocompatibility


#1

Has anyone investigated the patient contact bio compatibility of Form Resins?
Has anyone investigated the EO sterilization compatibility of Form Resins?


#2

Take a look at the dental resins - they supply biocompatibility information for those. At least some of them (and potentially all) are OK to autoclave as well.

I don’t know that you are going to find anyone who has actually run biocompatibility testing on any of the other resins.


#3

As @themedulla says, there’s some information for some of the Dental resins, and it’s generally an area of interest to Formlabs. I’m aware that some Formlabs customers are performing their own investigations into these questions, but I don’t know whether they’re sharing their results with Formlabs or with each other. You might get more helpful answers by reaching out through our Sales team to get in touch with an Applications Engineer/Consultant: https://formlabs.com/services/


#4

There is an excellent article written by Microdent that explains a lot about the regulation for the FDA and biocompatibility of dental materials. Unfortunatly Formlabs do not hold an establishment registration and are thus outside the expected quality control system of the FDA

The article: (From https://www.microndental.com/regulatory/fda-approved-cleared-3d-printer-resins)

FDA Approved 3D Printer Resins****strong text

Actually, there is no such thing as an “FDA Approved” resin for 3D printing. The term “FDA Approved” is reserved for high risk drugs and medical devices which have been approved via a very stringent premarket approval (PMA) process that goes well beyond the standard FDA 510(k) pathway. Read the article below on the FDA website for this very important distinction:

What is the difference between FDA-listed, 510(k) exempt, cleared and approved medical devices? (fda.gov archived)

FDA “Exempt” Biocompatible Class 1 Dental Resins
Most 3D printer resins used in dentistry today are exempt from the FDA 510(k) process, although the FDA requires that the source specifically list them as exempt before marketing them. 3D Printed resins marked as FDA 510(k) Exempt have been tested by the manufacturer to be biocompatible and are listed by that manufacturer or distributor for tracking purposes. In this case, it is the manufacturer, not the FDA, that is claiming that these products are exempt from the FDA 510(k) process, usually because they make limited contact with the patient.

In general, FDA 510K Exempt 3d printer resins must use ingredients that have been tested for biocompatibility (ie. cytotoxicity and other ISO 10993 testing), and are thus considered to not present a high risk to the patient when used in most Class 1 and some Class 2 dental indications where exemption from the 510(k) requirements is allowed.

In order for a resin to be listed as 510(k) Exempt, the manufacturer or distributor needs to have a Establishment Registration with the FDA, which indicates that the manufacturer is using a modern quality system and which allows the FDA to regularly audit the organization. Additionally, the packaging and labelling must meet FDA guidelines. Establishment registation requires a $4000+ annual fee and proof that the quality system meets minimal FDA guidelines. After the establishment is registered, the company can list their 510K exempt resins which will allow those products to be sold, shipped and monitored. Most importantly, these exemption listings are required for importing through customs, plus they allow all parties to track complaints about a specific resin back to the manufacturer.

510(k) FDA Listed or FDA Cleared Dental Resins
If a product is identified as “FDA Listed” or “FDA-Listed,” it means that the company who manufacturers or distributes it has completed an online listing theur the FDA Unitifed Registration and Listing System (FURLS). The term “FDA Cleared” refers to the subset of products that were cleared by the FDA because of a claim by the manufacturer or distributor that the product is substantially equivalent to another leglally marketed dental device. A 510K is substantiated by testing and it allows the resin to be used for a very narrow set of dental uses or indications. The listing may also specific very specific printing and post-processing steps needed to achieve the results demonstrated to the FDA in the testing process, including naming specific machines or means, so it is up to the user to make sure that they are processing the material in the same manner as was indicated. Any variation from the declared indications and processes is considered “off label” use.

List of FDA Tracked Dental 3D Printer Resins
The table below identifies 3d printable resins with can be legally imported into the US because they have been 510K listed or determined to be Class I devices and therefore exempt from the FDA 510K clearance process. Manufacturer’s update their own product listings every year, and can modify the list throughout the year, so the information above can be fluid as they rebrand and re-role the products (ie. start exporting, etc).

If you are aware of other FDA exemptions, clearances or listings in dental 3d printing, please send us an email via our contact form and we will add it to the list.

Establishment Indication Proprietary Names Class 510(k) Role or Equivalence
Bego (9611514)
Surgical Guide

VarseoWax Surgical Guide (482884) 1-NDP Exempt Foreign Exporter;
Repackager/Relabeler
Bego Custom Tray VarseoWax Tray (537052) 1-EHY Exempt Foreign Exporter;
Repackager/Relabeler
Bego Aligners VarseoSmile Splint (549382) 1-KMY Exempt Manufacturer
Vertex (8030452) Denture Base Denture E-Denture (541062) 2-EBI K162572
06/30/17 Eq: Dentca Denture
Base (K143033)
Vertex Retainers LT Clear; E-Guard; Ortho Clear; Rigid (483000) 1-DYT Exempt Manufacturer
Vertex Temporaries NextDent C&B; C&B MFH (483001) 1-ELK Exempt Manufacturer
Vertex Temporaries E-Dent 400; NextDent C&B; C&B MFH (483002) 2-ELJ Exempt Manufacturer
Vertex Surgical Guide E-Guide Tint; NextDent SG (504122) 1-NPD Exempt Manufacturer
Dentca (3009312537) Custom Tray Dentca Tray (437719) 1-EHY Exempt Manufacturer;
Spec Developer
Dentca Denture Teeth Denture Teeth (540012) 1-ELM Exempt Manufacturer
Dentca Denture Base Denture Base 2-EBI K143033
07/21/15 Eq: Trubyte
Denture (K032892)
Dentca Denture Base Denture Base II (539033) 2-EBI K162044
03/03/17 Eq: Dentca
Base #1 (K143033)
DeltaMed (3002789526) Temporaries e-Dent Temporary Resin (311115) 2-EBG K102776
02/18/11 Eq: Vita CAD TEMP
EnvisionTec (3012389497) Night Guard EGuard (516947) 1-DYT Exempt Manufacturer
EnvisionTec Surgical Guide EGuide (517520) 1-NDP Exempt Manufacturer
Structo (3014329597) Surgical Guide Structomer Guide (563712) 1-NDP Exempt Manufacturer
Dentis (3007031098) Impression Tray Z-Clear/SG, Z-Model, ZMD-1000B (479599) 1-EBH Exempt Manufacturer
Dentis Wax Cast Z-Castable, ZMD-100B Castable (479502) 1-EGD Exempt Manufacturer
Dreve (1000486347) Temporaries Multiple (266258) 1-EBH Exempt Contract Manufacturer;
Manufacturer;
Repackager/Relabeler
Dreve Surgical Guide FotoDent Guide; Multiple (459759) 1-NDP Exempt Contract Manufacturer;
Manufacturer;
Dreve Custom Tray Multiple (266258) 1-EBH Exempt Contract Manufacturer;
Manufacturer;
Repackager/Relabeler

These companies currently have FDA establishment listings with 3D printable resins:

Bego Bremer (9611514)
Vertex-Dental (8030452)
Dentca, Inc. (3009312537)
Dentis (3007031098)
DeltaMed (3002789526)
Dreve (1000486347)
Keystone (many, search “Keyprint” soon)
Structo (3014329597)
Whip Mix (3007057241)
Use this link to search establishment listings:
https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfRL/rl.cfm

These companies resell, relabel or specify other manufacturer’s resins, with or without their own FDA establishment licenses.

Formlabs - relabels NextDent resins
EnvisionTec - relabels NextDent as “E-Guard” and DeltaMed as “E-Dent”
Whip Mix - relabels Dreve (also makes Carbon SG resin for Carbon)
Sprintray - relabels NextDent and Dentis
Roland - relabels NextDent resins
Carbon - WhipMix and Dentca resins
The indications and/or categories of resins below do not currently require FDA listings by their manufacturers as the devices created with these resins do not require biocompatibility:

Dental Models - Resins for dental restorative models and dies
Ortho Models - Resins for orthodontic models, indirect bonding bracket trays , or where the final splint is created via theraforming
Gingival Masks - Resins for flexible gingival model inserts
Wax Cast - Resins for creating metal substructures and RPDs via loss-wax process
Regulatory Guidance Links
The FDA developed specific guidance for 510(k) submission regarding dental resins in 2005 in the PDF below:

Guidance for Industry and FDA Staff - Dental Composite Resin Devices - Premarket Notification [510(k)] SubmissionsDental Composite Resin Devices - Premarket Notification [510(k)] Submissions
The document above superceded the prior guidance provided regarding Dental Composites in 1998. The primary contact for discussion and feedback on this topic is Michael E. Adjodha at 240-276-3700 or via email at [email protected].
CURRENT US FDA DRAFT GUIDANCE ON 3D PRINTING

“Technical Considerations for Additive Manufactured Medical Devices”
Draft Guidance dated Dec 5, 2017 (first draft originally issued May 10, 2016) - 34 pages
https://www.fda.gov/downloads/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/UCM499809.pdfUS FDA SIG GUIDANCE ON MEDICAL MODELS
Aug 2017 Anantomical Model RSNA SIG Meeting
Including webcast and powerpoint links


Below are some papers and powerpoints that were presented to the FDA as part of developing the guidance for medical models:

FDA 2014 Powerpoint - //www.fda.gov/ucm/groups/fdagov-public/@fdagov-meddev-gen/documents/document/ucm418391.pdf" target="_blank" rel=“noopener” data-saferedirecturl=“https://www.google.com/url?hl=en&q=https://www.fda.gov/ucm/groups/fdagov-public/@fdagov-meddev-gen/documents/document/ucm418391.pdf&;source=gmail&ust=1523465299637000&usg=AFQjCNEt98mSHcRmbF8G6CpKi5UDfBd6kg”>https://www.fda.gov/ucm/groups/fdagov-public/@fdagov-meddev-gen/documents/document/ucm418391.pdf
SIG Paper - https://threedmedprint.springeropen.com/track/pdf/10.1186/s41205-016-0009-5
Stratasys Powerpoint - https://www.fda.gov/downloads/MedicalDevices/NewsEvents/WorkshopsConferences/UCM575729.pdf
3D Systems Powerpoint - https://www.fda.gov/downloads/MedicalDevices/NewsEvents/WorkshopsConferences/UCM575720.pdf
Materialise Paper - https://www.fda.gov/downloads/MedicalDevices/NewsEvents/WorkshopsConferences/UCM575728.pdf
ISO / ANSI STANDARDS

“Standardization Roadmap for Additive Manufacturing, Version 2.0”
AMSC 18-001 - Preliminary Final Draft as of 4/6/18 - 260 pages


CHINESE FDA (CFDA) GUIDANCE

Customized Additive Manufacturing Medical Device Registration - Technical Review Guidelines (Exposure Draft) - March 2018

Emergo Article - https://www.emergobyul.com/blog/2018/03/new-guidance-china-fda-3d-printed-medical-device-registration-rules-0
Guidance page (chinese) - http://www.cmde.org.cn/CL0063/6954.html
Guidance Doc (in Chinese Word Doc) - http://www.cmde.org.cn/directory/web/WS01/images/uL28jG2qNbGyr3U9rLE1sbU7NK9wcbG99C116Ky4by8yvXJ87Lp1ri1vNSt1PKjqNX3xPS4rz7uOWjqS5kb2N4.docx
Chinese FDA has historically been one of the toughest medical regulatory climates in the world for outsiders who want to get medical devices approved for sale in China. Read the emergo article above for key bullet points on the new proposed guidance.

SOFTWARE STANDARDS AND FDA GUIDANCE

2002 FDA Guidance on Software Guidance - https://www.fda.gov/downloads/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm085371.pdf
2005 FDA Guidance on Software in Medical Devices - https://www.fda.gov/downloads/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm089593.pdf
FDA GUIDANCE ON DENTAL RESINS

2005 Guidance on 510(k) for Permanent Dental Composite Resins - https://www.fda.gov/MedicalDevices/ucm071576.htm
THE FDA REGULATORY PROCESS

QSR 820 Quality System - https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/PostmarketRequirements/QualitySystemsRegulations/default.htm
Establishment Registration & Listings - https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/HowtoMarketYourDevice/RegistrationandListing/default.htm
510K - https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/HowtoMarketYourDevice/PremarketSubmissions/PremarketNotification510k/default.htm
Disclaimer - Micron Inc is not affiliated with 3D Systems – NextDent products are distributed in North America by Avadent.


#5

Formlabs sells a lot of resins so It should be taken case by case. The dental line is the only stuff that will have supplier data and the above post has addressed…120% of that topic.

I did Cytotox (MEM elution) on Durable and Dental SG a while back after EO sterilization and they both had 0/4 score (meaning they pass easily). EO discolors the durable turning it slightly yellow, it is probably more brittle too but I didn’t do any structural testing to it, but it “seemed okay”. The most important thing to get good cytotox results is to do a proper post cure. If it is cured then you should be fine. In that same study, I tested a Somos resin and it failed miserably with 4/4.

You will never get FL to back up the resins since they don’t want that risk (justifiably so) but if you really need them for your device then IMO it is worth at least doing cytox and going from there. The biggest problem to me is that FL is likely to change the revision level of non-dental resin which means your test data may no longer be accurate and you will have to figure out what to do in that case.


#6

Has the Formlabs supplied version of the Nextdent resins for dental use got traceability back to Nextdent (something for example such as batch codes marked on the cartridge / date of manufacture etc?) (I could not find it on the cartridge I have got)

If not, how does it become compliant in regards traceability / QC within the current FDA rules for a Class 1 (or 2) use?


#7

All of the Formlabs resin cartridges currently in my shop have batch/lot stickers down near the dispensers.