TOPIC: Some thoughts on 10% vs 20% vs 30%. Is it really all about absolute amount?

It's pretty common knowledge around here that Bellafill is .8mL a syringe and 20% PMMA, while Linnea is 1mL per syringe and is either 10% or 30%. However, are gains strictly correlated to absolute volume of PMMA spheres, or is there more at work?

A lot of people say that Linnea 10% is softer than 30%, but if it's all about the amount of spheres it shouldn't really matter. I suspect that the initial dispersion of the spheres within the carrier gel plays a part in both eventual volume gain and that mythical measurement known as G-Prime. If 10% solution really is softer than 30%, and the spheres are the same size profile, then some amount of the initial dispersion of spheres within the gel carries over into the eventual collagen matrix. I'm not saying it's a one to one correlation, some amount of absorption of the gel takes place before the initial scaffold is formed, but curious what percentage does carry through to the end.

Along those lines, the comparison between Bellafill and Linnea on a per mL basis may not be Linnea causes 50% more gains because it has 50% more PMMA per mL. It may be that Linnea only has 20% more gains, but has a higher G-Prime as a finished product indicating a higher concentration of PMMA spheres within the final collagen matrix. The Bovine collagen carrier in Bellafill might actually help in this regard by taking longer to reabsorb. This might give the body longer to form the initial scaffold before the carrier reabsorbs, leading to a less dense final product.

Just some thoughts from my Engineering brain.

Thanks for bringing this up, @EngrMike . So far I've just used HA, but I would like to get a better understanding of the different formulations of PMMA products and what the percentages mean.

The different percentages are just the concentration of microspheres within the gel carrier. Since a syringe full of microscopic plastic beads wouldn't inject very well, they are suspended in a gel carrier. For Linnea Safe (Avanti Derma), its a cellulose gel. For Bellafill (Rupeka, Sullivan, Rejuvall), it's a Bovine Collagen gel. Both typically also contain a small amount of lidocane painkiller, saline, and some preservatives.

Hi, also engineer, I made a spreadsheet to estimate volume increase wrt PMMA volume (i.e. corrected for concentration) and across my 2 rounds, even though the mix was different (5/15 & 8/10 (10%/30%)) the volume per PMMA was constant IIRC, don't recall the actual ratio I got exactly, but I think it was around 11:1 (11mL gained for every mL PMMA) (n=1)

Interesting, would definitely need a larger sample size since in both cases you got quite a bit of 30% and it’s fairly well known you get smaller gains in subsequent rounds. Thanks for the info.

Smaller gains from subsequent rounds is just math IMHO. For the same increase in volume, a smaller starting radius will increase more than a larger one.