Milling strategies for Angled Screw Channel cases

Brett Hansen CDT

Brett Hansen CDT

Well-Known Member
Full Member
Messages
1,677
Reaction score
102
We are starting to do more of these ASC cases on anterior implant crowns and bridges. I am having issues designing these cases so they don't break or chip in the mill The only reliable way I have found to design these cases is to make the screw channel not go through the entire restoration. I also don't have a good way to design the angled screw channel properly. Right now, i just set the case up so I am looking striaght down into the screw channel and then I just estimate ho much of an angle to tilt the Restoration before I put the hole in it. My mill is a Zenotec Mini and I have the basic milling software.
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
Im doing a ton of these.

When youre done with your anatomical design, make it a bit translucent so you can see your abutment.
Switch to expert mode. Select ATT, click allow any changes, select Remove, select extrude, choose the shape you want and scale it to the diameter and the length you need to cut from occlusal surface through crown bottom. Click apply. If you dont want it all the way through, you dont need to go into expert. Just select 'attachment' in the free form. That will keep your minimum thickness. To prevent chipping, go back to a small smoothing tool and round over the edges of the hole. That will also make it easier for the Dr to blend in the composite.
 
A

a3dl

Active Member
Full Member
Messages
153
Reaction score
14
In exocad there is Angled Screw Channel option. Must use screw channel (manual position).
 

Attachments

  • asc.jpg
    asc.jpg
    94.2 KB · Views: 43
Brett Hansen CDT

Brett Hansen CDT

Well-Known Member
Full Member
Messages
1,677
Reaction score
102
Too bad I am using 3Shape. lol
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
Its easier to fool people than to convince them theyve been fooled.

So...youre going to continue this or step up to Exo?
 
Brett Hansen CDT

Brett Hansen CDT

Well-Known Member
Full Member
Messages
1,677
Reaction score
102
This isn't a 3shape issue. This is a milling issue.
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
I am having issues designing these cases so they don't break or chip in the mill The only reliable way I have found to design these cases is to make the screw channel not go through the entire restoration. I just estimate ho much of an angle to tilt the Restoration before I put the hole in it.

Everything you listed is a design issue.
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
Everything you listed is a design issue.
Ill amend that...
Youre trying to do angled screw channels on a 4 axis mill. Thats a problem. I do it all the time, but thats a secret Im not willing to share.
 
Brett Hansen CDT

Brett Hansen CDT

Well-Known Member
Full Member
Messages
1,677
Reaction score
102
Ill amend that...
Youre trying to do angled screw channels on a 4 axis mill. Thats a problem. I do it all the time, but thats a secret Im not willing to share.

I have been a member here for almost a decade. This is the first time someone said they had a solution to a problem they weren't willing to share. That's fine. I have other resources, like the 3shape study group on FB.
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
"I wanna learn but its so hard. Just give me the answers"

Waaa
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
In addition to your X Y Z axis, your machine can (if your CAM software allows) limited rotation of the material. Thats your 4th axis. Screw channels must be aligned to this axis when nesting in your puck. You have the same ability on the intaglio side, so when nesting, you can (usually) tilt the part just a bit so you can get a greater differential between insertion axis and screw channel angle. The milling strategy will leave you with some cutting to be done by hand if your combined angle intaglio/screw channel exceeds the machines ability to rotate the puck.
 
Car 54

Car 54

Well-Known Member
Donator
Full Member
Messages
7,971
Reaction score
1,122
There are some things I don't bring up or share here on the forum.

Brett, have you tried "unlocking" the strategy in the Wieland CAM to adjust the unit the 10 degrees we can go with the 4 axis
to try to get a better angle of attack for the burs so they're not hitting the side wall of the channel?

Also, if you can find out from the study club how we can create a bevel on the occlusion of the access hole in 3Shape.
A couple of years ago a Ivoclar support tech showed me how, but at the time I wasn't doing those so I forget where the setting is.

I'm not sure if the advanced cam on my Mini helps out in some way?

edit: bevel
 
Last edited:
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
I have been a member here for almost a decade. This is the first time someone said they had a solution to a problem they weren't willing to share. That's fine. I have other resources, like the 3shape study group on FB.
Sharing. Thats quite a concept... donator.JPG
 
Sevan P

Sevan P

Well-Known Member
Full Member
Messages
3,413
Reaction score
641
We are starting to do more of these ASC cases on anterior implant crowns and bridges. I am having issues designing these cases so they don't break or chip in the mill The only reliable way I have found to design these cases is to make the screw channel not go through the entire restoration. I also don't have a good way to design the angled screw channel properly. Right now, i just set the case up so I am looking striaght down into the screw channel and then I just estimate ho much of an angle to tilt the Restoration before I put the hole in it. My mill is a Zenotec Mini and I have the basic milling software.

Wieland Cam Can easily do them i do them all the time no issues. Just need to set the paths correctly. Got screen shots of how you set the top channel? Bottom channel easy as usual on SR crowns. But with a mini you need to align the asc parallel with the A axis.
 
Last edited:
Brett Hansen CDT

Brett Hansen CDT

Well-Known Member
Full Member
Messages
1,677
Reaction score
102
Wieland Cam Can easily do them i do them all the time no issues. Just need to set the paths correctly. Got screen shots of how you set the top channel? Bottom channel easy as usual on SR crowns. But with a mini you need to align the asc parallel with the A axis.
Thanks Sevan. I sent you a PM on FB. I will send pics there
 
Brett Hansen CDT

Brett Hansen CDT

Well-Known Member
Full Member
Messages
1,677
Reaction score
102
There are some things I don't bring up or share here on the forum.

Brett, have you tried "unlocking" the strategy in the Wieland CAM to adjust the unit the 10 degrees we can go with the 4 axis
to try to get a better angle of attack for the burs so they're not hitting the side wall of the channel?

Also, if you can find out from the study club how we can create a bevel on the occlusion of the access hole in 3Shape.
A couple of years ago a Ivoclar support tech showed me how, but at the time I wasn't doing those so I forget where the setting is.

I'm not sure if the advanced cam on my Mini helps out in some way?

edit: bevel
Thanks for your response. I know my mill can't mill this bridge. That is why I sent it to core3D orginially.
 
Car 54

Car 54

Well-Known Member
Donator
Full Member
Messages
7,971
Reaction score
1,122
Thanks for your response. I know my mill can't mill this bridge. That is why I sent it to core3D orginially.

You're welcome.

I know unlocking the ~10 degree we have to work with our Minis can't make up for the angle at times.
If you want to see that option, I can show you in my feeble way, compared to Sevan who is way more advanced than I am.
I still struggle especially with upper anteriors singles and bridges that have the scooped out linguals that get milled in "2" planes.
If I had more time, better at my time management, I'd start sending some of these out, too.
 
Top Bottom