Biocompatibility testing for nasal prongs made of medical grade silicone

S

sandip179

#1
We are making some infant nasal prongs for an associated device, and were wondering, the requirements for biocompability testing for nasal prongs that are made of medical grade silicone.
 

Ronen E

Problem Solver
Staff member
Super Moderator
#2
Re: Biocompatibility testing for nasal prongs

Hello and welcome to the Cove :bigwave:

Where is this device / accessory going to be sold?

Generally, testing is based on the type of tissue being contacted and the duration of the contact, as detailed in ISO 10993-1.

Cheers,
Ronen.
 
S

sandip179

#3
The accessories will be sold in USA. They are similar to existing devices, except that the manufacturing process is slightly different to allow for a better fit. They will contact the face and the bridge of the nose for around a week. According to ISO 10993-1 specifications, these devices will be classified as surface devices, contacting the mucosal membrane, and as externally communicating devices to tissue/bone/dentin.

Since they are essentially similar to existing accessories and made with the same material (biocompatible silicone), do we need to perform all the tests marked in the ISO 10993-1 document?
 

somashekar

Staff member
Super Moderator
#4
Your device has to be bio compatible. You cannot grandfather this to similar existing device accessory, and since you have a slightly different process involved, risk assessment tells me that you need to have them tested per the standard for required bio compatibility.
 
#5
Since they are essentially similar to existing accessories and made with the same material (biocompatible silicone), do we need to perform all the tests marked in the ISO 10993-1 document?
Unfortunately, this would only be a viable strategy if you manufactured the "similar existing accessories", and hence could guarantee that the materials and process were the same.

In an ideal world (for manufacturers), there'd be a list of "medical grade" materials that would exempt biocompatibility testing. The reality however, is that different suppliers can use different processes and different levels of quality control to produce what is, on paper, the same material.
...as unlikely as it may be in most cases, these differences may affect biocompatibility, and hence testing normally has to be done case-by-case...
 
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Ronen E

Problem Solver
Staff member
Super Moderator
#6
The accessories will be sold in USA. They are similar to existing devices, except that the manufacturing process is slightly different to allow for a better fit. They will contact the face and the bridge of the nose for around a week. According to ISO 10993-1 specifications, these devices will be classified as surface devices, contacting the mucosal membrane, and as externally communicating devices to tissue/bone/dentin.

Since they are essentially similar to existing accessories and made with the same material (biocompatible silicone), do we need to perform all the tests marked in the ISO 10993-1 document?
I would take a less definitive approach than my peers here.

The answer to whether or not you can rely on the existing products depends on what "the manufacturing process is slightly different" encompasses. If, as pointed, the existing products are yours, and you know what the differences are with 100% confidence, and those differences are of a certain nature (say, a small geometrical change in a molding tool) then perhaps you could justify not retesting.

If you do have to test, please note:

1. The FDA has a modified testing requirements matrix, based on ISO 10993 but not identical to it. Some additional tests might be required, based on various factors.

2. Since the change is (apparently) not big, you could perhaps suffice with (biocompatibility) equivalence testing. This is a comparative testing that aims to establish that the 2 (different) designs are equivalent from a biocompatibility point of view. It is usually cheaper and easier that the full battery of tests required for a completely new device. The best would be to bring it up with your test lab.

Cheers,
Ronen.
 
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#7
Since the change is (apparently) not big, you could perhaps suffice with (biocompatibility) equivalence testing. This is a comparative testing that aims to establish that the 2 (different) designs are equivalent from a biocompatibility point of view.
Interesting. I've never heard of this. Presumably you'd have to know beforehand the details of the process of the original (biocompatible) material, no? ...which I imagine would normally be quite difficult to obtain. ....unless of course, it was you that was using the original (biocompatibly verified) material...
 

Ronen E

Problem Solver
Staff member
Super Moderator
#8
Interesting. I've never heard of this. Presumably you'd have to know beforehand the details of the process of the original (biocompatible) material, no? ...which I imagine would normally be quite difficult to obtain. ....unless of course, it was you that was using the original (biocompatibly verified) material...
No. It's a lab test-set that compares the devices in their ready-to-use state. Unfortunately I can't provide specific details without going back to test reports from 2008 (last time I was involved in such testing).
 
#9
Hmmm... so is the process just a material analysis (like some kind of spectroscopy) and comparison? If so, I wonder what criteria are set for biocompatibility equivalence? (...because material analysis and comparison of just about any two materials from different sources is likely to identify some differences, even if on paper the materials are the same...)

Also, is there solid grounds (in terms of FDA regulations) for using such equivalence testing in lieu of 10993 testing to support biocompatibility claims?
...does the test lab have to adhere to a certain consensus standard when performing equivalence testing?
 

Ronen E

Problem Solver
Staff member
Super Moderator
#10
Hmmm... so is the process just a material analysis (like some kind of spectroscopy) and comparison? If so, I wonder what criteria are set for biocompatibility equivalence? (...because material analysis and comparison of just about any two materials from different sources is likely to identify some differences, even if on paper the materials are the same...)

Also, is there solid grounds (in terms of FDA regulations) for using such equivalence testing in lieu of 10993 testing to support biocompatibility claims?
...does the test lab have to adhere to a certain consensus standard when performing equivalence testing?
If you are after thorough answers to all these questions I suggest you talk to one of the larger test houses (e.g. NAMSA) because my experience on that might be outdated. I just thought it's worth mentioning because in the past it was quite handy.
 

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