Hi 4johnybravo,
Sorry for the delay and thanks for the nice words.
I will try my best to answer your Q.s as much as I can :-
The most important thing we should know that for an example if you increase the total body\'s surface area of an implant in our body ---> you will increase its strength.
E.g A fenestrated alloplastic sheet implant (e.g. for hernial repair) will be initially softer than the solid sheet implant but later on due to fibro-vascular infiltration through the fenestrations (i.e. which has an increase in the total surface area) will be stronger than the solid one :-
(( [0020]In one embodiment, the biocompatible alloplastic mesh implant is a solid sheet. Woven structures are advantageous, as well as microporous materials. The implant may be fenestrated to allow additional fibrovascular infiltration through the mesh scaffold. The fenestrations may be formed in a variety of geometric shapes and sizes. Initially, a fenestrated mesh implant may not be as strong as a solid sheet implant. However, because of the increased surface area and the potential for fibrovascular infiltration through the fenestrations, a fenestrated implant will ultimately be stronger than a solid sheet implant. The fenestrations may also be used to more securely anchor the mesh implant to the host.))
www.faqs.org/patents/app/20080299172#b
1- First of all we have to know how many pmma beads (e.g.a diam. of 40 microns) are in 10%, 20% and 30% conc. in 1 cc. :-
10% ---> around 3 millions pmma beads / 1cc.
20% ---> around 6 millions pmma beads / 1cc.
30% ---> around 9 millions pmma beads / 1cc.
So that means 1% pmma conc. contains 300,000 pmma beads.
So now to answer your 1st Q. :-
Let us take the 20% conc. as for an example with the 40 micron and 100 micron beads and to have a comparison between these two different sizes :-
First of all we should know that the 20% conc. means it contains :- 20% pmma beads and 80% collagen (or CMC) and it will be the same for either the 40 micron or for the 100 micron bead ( i.e. in volume) so :-
1 cc. of 40 micron @ 20% will have 6000,000 beads, but
1 cc. of 100 micron @ 20% will have 384,000 beads only :-
I will try to explain it much better :- each 40 micron (radius 20) has a volume of (33,510.322 micron3) and in 1 cc (i.e. 6 millions beads) a total volume of (201,061,932,780 micron3) and this total volume of the beads in 1 cc. will be also the same for the100 micron diam. beads @ 20% ; but the volume of a single 100 micron bead (the radius of 50 micron) is (523,598.78 micron3) so when you divide the total volume of the 100 micron beads @20% in 1cc. over the volume of a single 100 micron bead ---> will give you 384,000 beads .
So now the TOTAL surface area of the whole pmma beads all together (and not for a single bead) is the most important point for the amount (the volume) of the new collagen formation .
You have mentioned a single 100 micron bead is more than double the size of a 40 micron bead and it is true also in regard of the surface area :-
A single 40 micron bead ---> has a surface area of (125.664 micron2)
A single 100 micron bead ---> has a surface area of (314.159 micron2)
But the number of the beads as we mentioned before is different in 1cc. ( 6 millions beads of 40 micron @20%) + ( only 384,000 beads of 100 micron @20%).
So the total surface area of :-
1- 6000,000 beads of 40 micron =753,984,000 micron2
2- 384,000 beads of 100 micron =120,637,056 micron2
In summary :-
40 micron beads will give you around 6.25 X MORE total surface area than the 100 micron beads do.
So thats why the smaller micron beads will give you more volume of the new collagen formation and also much firmer than the bigger micron beads.
E.g. if we have two pieces of plexiglas (pmma) with exactly the same size (volume) :- one is divided into 100 of spheres and the other one into 1000,000 microspheres (sure they will be smaller in size than the 1st one) and both implanted into the body after few weeks the 2nd one will give you more volume gain (i.e. the newly formed collagen) and also much firmer.
As you know Metacrill\'s conc.s:-
2% ---> suitable for skin wrinkles.
10% ---> suitable for fat augmentation, i.e. nearly the same texture of fat.
30% ---> suitable for muscle augmentation, i.e. nearly the same texture of muscle.
40-45% ---> for bone reconstruction, i.e. its texture will be the same as bone (it is used for skull bone defect reconstruction e.g. frontal bone defect).
So as you increase the number of the beads / 1 cc.(i.e. as you bring the beads close to each other) ---> it will increase the firmness of the new collagen.
I am sure nobody would like to have e.g. a piece of a bone-like graft (i.e. from the 40-45% pmma) in his biceps, lol.
2- With every transdermal needle stitch through the skin, one will introduce 100s of bacteria, mostly Staph. epidermidis, which are sitting on the undersurface of the skin dandruffs and are never reached by disinfectants .
Furthermore, any injectable is surrounded by macrophages on day 2, e.g. if you introduce bacteria, which you do, they are phagocytosed right away. However, that does not interest the FDA : they want to know black or white : zero or any amount of bacteria.
Because they have read that the UV-light may make cracks in Plexiglas, they forbid UV-sterilization but asked for ethylene-oxide gas, which takes weeks to evaporate from the microspheres.