jawsurgeryforums.com
General Category => Functional Surgery Questions => Topic started by: newchin on July 09, 2014, 12:45:11 PM
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I had ha paste augmentation and wondering how long it is malleable?
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It seems to depend on the technique used. Arnett and Gunson say they can mold it for weeks afterward while Mommaerts said it was only moldable during the surgery. Who was your surgeon?
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I believe Arnett/Gunson can mold it for up to 6 weeks after surgery. I don't know about others.
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Try not to worry too much just yet 3 weeks is really too early to tell, it's very common to have asymmetric swelling so that might be throwing things off.
Tell your family and friends to shut the f**k up ;)
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It seems to depend on the technique used. Arnett and Gunson say they can mold it for weeks afterward while Mommaerts said it was only moldable during the surgery. Who was your surgeon?
3 guesses...
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Unless your surgery was performed by a certain Belgian surgeon then I wouldn't worry too much about it just yet. I'm not sure how hard it is to remove HA but I can't imagine that it's easy.
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Unless your surgery was performed by a certain Belgian surgeon then I wouldn't worry too much about it just yet. I'm not sure how hard it is to remove HA but I can't imagine that it's easy.
its very hard
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its very hard
Which surgeon said that? Many don't have a lot of experience with HA.
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Which surgeon said that? Many don't have a lot of experience with HA.
several cranio and maxilla doctors. the problem is its brittle
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several cranio and maxilla doctors. the problem is its brittle
Do you think it's fully hardened at 3 weeks?
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i remeber dr byrd telling me its moldable for 2-3 week but every day will be hardsr
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several cranio and maxilla doctors. the problem is its brittle
Exactly. It will be more brittle than bone. Bone contains collagen and several other proteins that give it tensile flexibility and 'spring' as well as a bunch of trace elements. The crystal structure is quite interesting - it's basically a co-crystal of nano-crystals of HA and rows collagen fibrils. (Enamel is a little different in that in contains less protein and more fluorine has larger, more organised HA crystals - making it stronger, but more brittle)
As far as I know they mix the HA with organic products like blood plasma and collagen. Also I think they they use HA nanocrystals, rather than growing them with the collagen from the liquid phase Over time some of the organic elements will dissolve somewhat so I am sure that HA paste will contain less collagen than regular bone and the crystal structure will not be nearly the same. It's not called 'bone cement' for nothing....it is a very crude approximation of bone (although there is are some interesting in vitro studies that have been done on the nucleation of HA crystals and how it's directed by proteins etc)
Anyway, I digress - how long it's mouldable for will depend how its mixed although I'm surprised that A&G can mould it for as long as they claim - I'm guess they're using more organic product in their mix. I think the only way to remove it would be to file it off :-\
If it's a small asymmetry you can a probably disguise it somewhat with some of the more dense hylauronic acid fillers as a short-term measure. In the longer term, if it's bad then try and push your surgeon to add more to the smaller side
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You seem to know a lot about HA Tiny. I'm assuming I'm basically screwed if I want it removed then?
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You seem to know a lot about HA Tiny. I'm assuming I'm basically screwed if I want it removed then?
guyuron might be able to remov it
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you know that by mold is means literally just that. you are told to close your eyes while the surgeon presses his fingers/squeezes your face and attempts to shape the HA paste into an "attractive shape"
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you know that by mold is me. s literally just that. you are told to close your eyes while the surgeon presses his fingers/squeezes your face and attempts to shape the HA paste into an "attractive shape"
One non-syndrome lefort iii paper that I have says HA paste is imprecise for orbital applications. Albeit the paper is 20 years old. But how the hell does A&G manage orbital augmentation then? They are the only ones to do so.
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One non-syndrome lefort iii paper that I have says HA paste is imprecise for orbital applications. Albeit the paper is 20 years old. But how the hell does A&G manage orbital augmentation then? They are the only ones to do so.
I've never seen any before/after pictures from them where orbital augmentation was done. Who knows, they might not produce good results when it comes to that area. Overall I'm not seeing any good results at all, plastic surgery or not, when it comes to infraorbital augmentation. Even if I could get the HA out it seems that I'm screwed either way.
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I've never seen any before/after pictures from them where orbital augmentation was done. Who knows, they might not produce good results when it comes to that area. Overall I'm not seeing any good results at all, plastic surgery or not, when it comes to infraorbital augmentation. Even if I could get the HA out it seems that I'm screwed either way.
I can tell you from years of experience. If you have an orbital rim deficiency you are cursed. its very very hard to fix and you have few overall options and very very few good options
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I can tell you from years of experience. If you have an orbital rim deficiency you are cursed. its very very hard to fix and you have few overall options and very very few good options
Modified lefort iii?
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Modified lefort iii?
not sure yet.
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I was told 6 weeks- and it gets progressively harder to mold after week 4. Imagine that crackling noise of rice krispies, yes thats what it sounds like lol. It also feels strange, it doesnt fully feel like its part of you yet it isnt too noticeable, its hard to explain. If I ever lay down on my cheeks you notice something is there.
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Hey Cmonster,
Can you still, currently feel it when laying on your cheeks, or was that just at the beginning? Is/was it bothersome, or just weird?
Thanks!
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I don't want to get fillers to even it out as it's too big in general, and to add more to the lesser side would make me look worse lol oh man I could honestly cry. Could I possibly apply pressure myself to the area and see if it molds? Or could I cause some damage?
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I don't want to get fillers to even it out as it's too big in general, and to add more to the lesser side would make me look worse lol oh man I could honestly cry. Could I possibly apply pressure myself to the area and see if it molds? Or could I cause some damage?
Who's your surgeon? (PM if you want).
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You seem to know a lot about HA Tiny. I'm assuming I'm basically screwed if I want it removed then?
I got to study the crystal structure of bone at university as part of my macromolectular structures course....the prof was basically lecturing his own research. Literally the easiest module I did that year ;D
Anyway there's no reason they can't file it down but it's not easy because it's harder than bone. And then the metal screws will get in the way and they probably can't turn the screws if they're embedded in the cement. So I guess it can be filed down as far as the screws but no futher
IMO, HA paste just isn't accurate enough for gonial angles. Cheekbones maybe
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I got to study the crystal structure of bone at university as part of my macromolectular structures course....the prof was basically lecturing his own research. Literally the easiest module I did that year ;D
Anyway there's no reason they can't file it down but it's not easy because it's harder than bone. And then the metal screws will get in the way and they probably can't turn the screws if they're embedded in the cement. So I guess it can be filed down as far as the screws but no futher
IMO, HA paste just isn't accurate enough for gonial angles. Cheekbones maybe
I'm beginning to think that HA paste applications are very very limited. Maybe filling gaps i.e. smoothing genioplasty and BSSO discontinuities, and that's about it.
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I got to study the crystal structure of bone at university as part of my macromolectular structures course....the prof was basically lecturing his own research. Literally the easiest module I did that year ;D
Anyway there's no reason they can't file it down but it's not easy because it's harder than bone. And then the metal screws will get in the way and they probably can't turn the screws if they're embedded in the cement. So I guess it can be filed down as far as the screws but no futher
IMO, HA paste just isn't accurate enough for gonial angles. Cheekbones maybe
Is it harder than bone?
I read that HA paste breaks / shatters easier than bone, which causes problems for some depending on where it's placed. Is this untrue?
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Is it harder than bone?
I read that HA paste breaks / shatters easier than bone, which causes problems for some depending on where it's placed. Is this untrue?
Yes, it is harder than bone because it contains a lot less collagen, I would also surmise that the crystals are larger. That also makes it more brittle. Bone is really made of mineralised collagen -
(http://web.mit.edu/mbuehler/www/research/f101.jpg)
(http://bme240.eng.uci.edu/students/10s/ktauro/images/ss_img20.jpg)
(http://www.robaid.com/wp-content/gallery/humorg/mit-3d-printed-bone.jpg)
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Yes, it is harder than bone because it contains a lot less collagen, I would also surmise that the crystals are larger. That also makes it more brittle. Bone is really made of mineralised collagen -
(http://web.mit.edu/mbuehler/www/research/f101.jpg)
(http://bme240.eng.uci.edu/students/10s/ktauro/images/ss_img20.jpg)
(http://www.robaid.com/wp-content/gallery/humorg/mit-3d-printed-bone.jpg)
Could you elaborate a bit more on how that makes it more brittle? Just how much more brittle? What kind of force would be required to shatter it?
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Have you had your second consultation with Triaca yet? I'd like to hear what he has to say about removing HA.
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Could you elaborate a bit more on how that makes it more brittle?
Collagen is an alpha-helix. As such, at the molecular level, it is able to twist, bend, stretch and compress. The secondary structure is held in place by hydrogen bonds, which are weak and can stretch, break and reform easily (and even covalent bonds can stretch/bend somewhat) The collagen in bone is lined up in sheets and bundles, which gives bones a degree of spring and flexibility.
Also, the HA crystals in natural bone are very small - nanocrystals. Means they're less likely to shatter simply because of their size; they're also less organised so have a less strict 'crystal plane'. Meaning they're softer, but less brittle.
Compare that to HA pastes - the collagen fibres are more randomly distributed so cannot bend or stretch en masse to absorb a shock. The inorganic part, the HA, is probably made up of much larger crystals that are more organised than 'native' HA. Held together primarily by ionic bonds, the material cannot absorb any of the force on a molecular level so it will just snap...it's related to electrostatic repulsions caused by a shift in the crystal plane. Ionic solids are brittle by nature; ionic crystal structures are more rigid (ie. less flexible) than covalently bonded materials (even though the bonds themselves are somewhat weaker)
Just how much more brittle? What kind of force would be required to shatter it?
I'm a chemist, not a physicist :P :P But it's really impossible to say without experimentation and it would also depend on the 'mix' of the HA used
Incidentally, young bones have more collagen than older ones, which is one of the reason why older bones are more brittle
The most exciting current research is stuff like this -
http://www.nbcnews.com/id/5832265/ns/health-cloning_and_stem_cells/t/new-jaw-bone-grown-mans-back-muscle/ (http://www.nbcnews.com/id/5832265/ns/health-cloning_and_stem_cells/t/new-jaw-bone-grown-mans-back-muscle/)
Of course, stem cells are key. You want to grow real bone, you're going to need osteoblasts, a framework, and time. (of course, in the meantime, it would definitely be possible to get bacteria to produce the kind of dense collagen than you get in bone)
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Thank you for taking the time to write that. I always enjoy learning about that stuff.
You mentioned about getting a bacteria to grow the kind of dense collagen that is present in bone. Did you mean to grow that inside the hydroxyapatite?
It's an interesting thought but given that I've never seen it mentioned before I doubt anyone actually offers it.
My main concern now is that if I were to get HA paste applied on the infraorbital rim there would be a risk of shattering it. So how easily it shatters is of huge importance. I'd hate to take a knock and literally have part of my face break off.
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You mentioned about getting a bacteria to grow the kind of dense collagen that is present in bone. Did you mean to grow that inside the hydroxyapatite?
No no no I meant in the lab. It's a lot easier to get bacteria to grow you pure proteins than eukaryotic cells. That said, a good approximation of bone will be impossible without stem cell. It's osteoblasts that lay down the collagen fibres in the right way i.e. in organised bundles
My main concern now is that if I were to get HA paste applied on the infraorbital rim there would be a risk of shattering it. So how easily it shatters is of huge importance. I'd hate to take a knock and literally have part of my face break off.
Hmmm, good point. I was considering getting HA to my cheekbones when I got my revision rhino. I must have mentioned to the surgeon that I did MMA but he never said that would be an issue. Glad you brought it up though, maybe I shouldn't be getting HA on my cheekbones!
I think orbital rim though would probably be fine...it's not exactly as exposed an area as the jaw or cheekbones. Are you into boxing or other contact sports?
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HA is not that hard. The paranasal area where I had HA injected isn't exactly soft but it's definitely not super hard either. I'm not sure I would recomend taking punches in the face either way.
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No no no I meant in the lab. It's a lot easier to get bacteria to grow you pure proteins than eukaryotic cells. That said, a good approximation of bone will be impossible without stem cell. It's osteoblasts that lay down the collagen fibres in the right way i.e. in organised bundles
Hmmm, good point. I was considering getting HA to my cheekbones when I got my revision rhino. I must have mentioned to the surgeon that I did MMA but he never said that would be an issue. Glad you brought it up though, maybe I shouldn't be getting HA on my cheekbones!
I think orbital rim though would probably be fine...it's not exactly as exposed an area as the jaw or cheekbones. Are you into boxing or other contact sports?
Hold on, I was thinking about this in the shower... shower thoughts...
Does bone grafting resolve these issues? Wouldn't it have the collagen in it already needed to make it less brittle?