margin design

[Brett Hansen CDT]

I have been having some issues with short margins on some of my milled zirconia. The milling center I use has told me that they have trouble milling my designs due to the way the margins are designed. They asked me to add material to the margins so there isnt a concavity, which is causing it to chip during the milling process. I am having trouble giving them what they need. I also don't understand why my DWOS would put out a margin design that is hard to mill. Here is a pic of a margin that came back short. Any help would be greatly appreciated.

 

[cadfan]

Load up the STL to dropbox and or make a shot off the margin settings

 

[Brett Hansen CDT]

i am new to dropbox. hopefully this worked.

https://www.dropbox.com/s/7o1aymnrl4c56g2/Hunter_pauley_vickery_bridge_3_4_5_C2.stl

 

[cadfan]

Your settings for the margin is ca. 0,12 mm this is real the limit that can be milled depend on a few things better make 0.15 or 0.2 to be 100 % safe see the pic below

 

[Brett Hansen CDT]

Thank you for looking at this cadfan. This is so frustrating.

 

[CoolHandLuke]

naw, come now. the "limit" of what can be milled has little to do with the thickness at the edge, it has everything to do with the shape of the edge.

you need to make sure your margin has a CONSISTENT, EVEN, FLAT angle of taper. not wibbly wobbly, wavy or hooked.

your margin is copying the Jprep with a J at the margin line. you need to fix this.

more to the point your milling center needs to realize that if you smarten up your designs with more consistent and even margin angles then they can mill all the way down to .05 margin thickness without chipping.

 

[Brett Hansen CDT]

Besides the margin being short, this bridge also required alot of adjusting when it came back to get it to seat. Are there are any setting I should change to improve the fit?

 

[Brett Hansen CDT]

Luke, how do i do this? If I use the "add" tool, all it does is thicken the margin, it doesn't change the design of the margin. Is this is DWOS thing?

 

[CoolHandLuke]

i don't know anything about Dental WIngs, i can't help you there.

 

[imagedental11]

i dont know if dental wings has this but border design needs to be changed, i use 70 degrees on the crown border parameters and no more chipping

 

[cadfan]

0.05 mm ??? not inch ???

 

[Brett Hansen CDT]

Luke and Cadfan, I made the changes you suggested. Can you look it over again?
https://www.dropbox.com/s/7o1aymnrl4c56g2/Hunter_pauley_vickery_bridge_3_4_5_C2.stl

Thanks!

 

[cadfan]

2.5 settings
http://www.wieland-dental.de/uploads/tx_pxwldownloads/ZENOTEC_Cad_Bedienungsanleitung_e.pdf



have a look at yours palatinal thinn and make some cuts to learn with magics its for free

http://software.materialise.com/minimagics

 

[CoolHandLuke]

cadfan has it.