so here's the production of a Brooks or  Crown start to finish this is the Dennis  

polyvinyl siloxane impression so we poured it up  in stone there's the stone model right there of  

the prep arch and as you can see this is being  put into a three shaped scanner we want to get  

this into the digital environment as quickly as  possible because everything works better for us  

in the digital environment it's so much more  consistent if the dentist had sent a digital  

impression then we would start right from that  but we had a conventional impression so there's  

no really good impression scanners out on the  market so we still have to pour the model in  

stone and now we're going to scan it and bring it  into the digital environment so it's going to look  

like the dentist took a digital impression in the  mouth it's just that we had to do it ourselves and  

it's not quite as accurate as if the dentist is in  the mouth to be honest because there's distortions  

and poly vinyl and dental stone there's the  articulated model so now we're going to be able  

to scan that from the side and now we can see  exactly how much reduction we have between that  

prep tooth and the opposing to no more guessing  on our part and this is one of the big benefits  

for dentists who have digital impression scanners  is that they can see their reduction actually in  

the mouth we're going to mark the margin here and  move it around and try to be true to it as long  

as the dentist has left us enough room which this  dentist really did you can see we've got an ideal  

anatomical pattern that it's going to propose for  that particular crown if there's not enough room  

that it has to start making changes we can make  little changes here prove the doctors request  

if we need to on the contacts but most of the  time with us designing it the same way every  

time most doctors don't have us make many changes  you can see that the different crown designs here  

are all being nested these are all going to be a  two crowns for example and so unlike Emacs which  

is milled in a small block blocks or crowns are  milled from a big white hockey puck so we do a  

bunch of shades a bunch of crowns at the same  time so here's that one you can see there's a  

barcode that has to be matched up that's the  enlargement factor because believe it or not  

well one of the things that we hear about these  crowns is that oh they fit better than any crown  

I've had before from you guys the amazing thing  is you can see here they're milled roughly 21 22  

percent bigger than the final crown is going to be  and that's what the enlargement factor refers to  

so there's an exact factor for each block based  on the weight and density of the zirconia once  

that's been measured that's what that barcode  tells the milling machine so it knows exactly  

how much bigger to make those crowns you can see  they look huge they look like veterinary crowns  

they don't look like human crowns and they're  going to shrink while they're in the oven and  

amazingly they're going to end up fitting just  fine when we go to you when you go to try them  

in the mouth so the cut cut sprues are removed  they're cut out of the disk and they're put on  

those little alumina oxide balls that you can see  there because these are going to shrink roughly  

21% while they're in the oven for nine hours  we need those little ball bearings to help so  

that when the crown actually shrinks there's no  contact between the tray and the crown or else it  

would distort the shape of it so this way as the  crowns shrink during the nine hours Center those  

ball bearings roll underneath the crown so the  crown ends up being exactly the same shape it just  

shrinks by whatever 21 to 22 percent based on the  exact enlargement factor for that particular block  

once it comes out we do a little sandblasting to  get it all cleaned up and now we're going to put  

some color on it so this is some staining that's  being done to match whatever color the dentist has  

requested the block started off as an aide to but  there's still a degree of characterization that  

needs to be done typically we're going to have  some translucency by the cus tips and we're going  

to have some increased chroma in the gingival  third here we're spraying the glaze on this is  

what relah and gordon christensen aren't huge  fans of because that glaze we put on there that  

makes it look pretty when it comes out of the  oven that glaze actually is rougher has bigger  

particle size and is rougher than the zirconia  oxide underneath and so really the only reason  

that a Brooks our crown initially wears opposing  enamel is because of that glaze on the outside and  

as the result Rella has asked us is there any way  you can guys can just polish the outside of those  

crowns so for any doctor who asks for it we do  just polish the outside of the crown without  

any glaze it's not as pretty but it doesn't where  the opposing it all without the glaze as part of  

our quality control we use the Vita ez shade to  verify that it is in fact an a2 crown before we  

send it out to the doctor and color a little bit  different that's why we like this computer device  

to make sure that we're sending out the crown in  the exact same shade that the doctor requested

you