Denture building 1
Denture building 2
OKOK so I read back what I’ve written in the last Denture building post, and the second last paragraph is kinda confusing… Hahahaha… Nevermind, you’ll see what I meant in this post… I think this is the last post for Denture building, it just lacked the final product part, coz I’m not done with it yet…
So… the next thing that should happen is to seal the wax pattern (base plate + occlusal rim + artificial teeth) to the cast by using wax, which I didn’t show… Hehe.. And then, it’s time for dearticulation… You can see the remains of the mounting plaster on the articulator… The flask is now opened (by prying it, LOL), comprises 3 parts, the one the upper cast is sitting in is the lower portion of the flask, which we’ll fill it with plaster to hold the cast… Oh ya, this is the working table of my Dental Materials lab in dental college, hehe…
The cast is mounted on the lower portion of flask… By using plaster…
And then now we cover the lower portion with the middle portion (body) and then pour plaster, then finally cover it with the toppest part… This is one of the most crucial part as the plaster that’s poured now will become the mould of the final product, any air bubbles trapped will be produced in the mould and ultimately in the final product… After the plaster sets, the function of the wax and base plate ends here as the shaped has already been transferred to the plaster mould… The whole flask is placed into hot water to separate the upper and lower flask, and hot water is poured into the mould to remove all the wax… This is known as dewaxing…
Thus now there’s no more wax or baseplate liao, only the artificial teeth remain in the mould, a closer look at the mould… Now only the root part of the artificial teeth is seen…
The mould is ready for introduction of resin… Before that we’ll hafta apply a layer of separating media to prevent the resin to stick to the plaster… Unfortunately I didn’t apply enough and the upper denture turned out to be fully sticked to plaster… And a great deal of trimming is done to remove the white patches… Sigh…
The resin we use comes in powder and liquid form, which after they’ve been mixed will turn into a dough-like matter… We put the dough nicely into the mould and cover the other half of the flask and by using a clamp we close the flask slowly… After that the flask is reopened for removal of excess resin…
Understand? Underneath the pink resin is the artificial teeth… So the process is repeated a few times to make sure that ther’s no more excess resin and finally it’s closed for the last time… After waiting for 30 minutes for the pressure inside the mould to equalize (as well as for the powder and liquid to become more homogenous), we can finally “cook” the resin…
The resin is of heat-cure type, meaning that by mixing the liquid and powder alone won’t turn the thing into a plastic, we’ll have to HEAT it… So we’ll put the assembly together with the clamp into a big pot of hot water, and the heating cycle takes hours according to book, but we just heat it for 1 hour only.. Hahaha…
And after all the heating, and letting it to cool itself, we can open to flask and break off the plaster to retrieve the denture… And as I’ve said earlier, I didn’t apply enough separating media, so…
And now a little reunion of upper and lower denture… Hehe…
In case you asked where’s the upper cast?… Again it’s because of not enough separating media…
I superglued it, I hope the bitch won’t bitch about it…
And so we repeat the whole process for the lower denture, starting from the flasking…
And during dewaxing, something terrible happened – the whole lower portion disintegrates, and a small part of the cast broke also… Cast broken before packing of resin = destroyed final denture… Luckily it turned out right for the outer surface… Phew… And then now the deflasking for the lower denture…
Finally… The reunion of the pair of dentures… Hehehe…
And now they are ready to be finished and polished…
And the creator… ^_^
I think this should be the end liao loh…
Recent Comments