Crown and Bridge
Application Guide for Printing Castable Materials
Application: Crown and Bridge
Subtype: Cast
Resin: QuraCAST
Software: Omega 3D
Dental Model Orientations
Dental models may be printed a number of different ways:
A. Horizontal: Accurate, requires the least print preparation time, and prints the fastest for individual prints, but takes up the most build platform space
B. Angled (10-15°): Highest possible accuracy and smoothness, but requires the most print preparation and support cutting time
C. Vertical: Fastest printing method for mass production, but slowest for individual prints
When should I print angled?
The angled orientation is best used when accuracy and smoothness are more important than the time invested to make the print. For example, when aesthetics are important, such as when prints are going to be attached to articulator interfaces and shown directly to patients, then it may be better to print at an angle.
When should I use a different orientation?
In general, the angled orientation takes the most work to set up and to print. The horizontal orientation is not as smooth and may encounter resin leakage holes, but generally meets most accuracy needs without the set up time. More models can be printed in less time with the vertical orientation. If your prints are being used in the lab setting, either other orientation may suit your needs better.
1. Print Analysis
A. Critical Areas – Do Not Support
- The most important part of this print is the fitting area of the crown and bridges against the model or implant attachment. As such, the crowns should be positioned so that their fitting area is facing away from the build platform.
B. Intended Support Area
- If the fitting areas are facing up, then the tooth surface should be facing the build platform, and therefore will be the support surface. This does mean that a lot of additional aesthetic work will be necessary, but it is easier to do this work than to manually adjust the fitting.
2. Orientation
A. Position the print as horizontally as possible, with the fitting area of the die facing upwards.
There will be a lot of tooth surfaces on the bottom, and it may be hard to make it flat. It does not need to be perfect; your goal is to just make the fitting area not require supports.
B. Raise the part off the platform.
- Height : 1.8 mm
3. Supports
This type of print requires a substantial number of supports, but generally can use all supports of one type. There will be many local minimum points which require supports, as well as space between supports which will usually almost entirely consist of overhangs.
Support Parameters
- Top Radius: 0.400 mm – 0.70 mm
- Bottom Radius: 0.80 mm – 1.20 mm
- Omega 3D Setting: 0.45 mm – Crown, Die, Splint
Tip
Ackuretta recommends starting this print using Automatic Supports. After the majority of the supports are made, use Manual Supports to adjust the supports. If the tops of supports are too close together, remove all of those supports, and replace them with a slightly larger support.
4. Base
Ackuretta recommends adding a base to almost all supported prints. Adding a base allows the print to stick to the build platform securely, and it makes the print easier to remove during post processing.
- Base Thickness: 0.150 mm – 0.250 mm
- To add a base in Omega 3D, go to the BASE tab, and then click Add Base.
Warning
A thicker base does not improve print performance. A base of 0.400 mm or thicker may even make a print less likely to succeed.
5. Print
Arrange all of the crowns and bridges that you want to print.
In Omega 3D, select your Machine and Resin from the Project tab on the left side. Then go to the Slice tab to select your Material profile. Your material profile contains the layer thickness and may be calibrated for specific types of prints.
- Resin: QuraCROWN
- Recommended Layer Thickness: 0.050 mm
- Recommended Profile: Choose the “Crown” setting, if available for your printer. Otherwise choose the “Default” setting.
Diplo / Ackuray Print Settings
- Buffer Layers: 5 layers
- First Layer Curing: ×9
FreeShape 120 Settings
- Burn-In Layers: 6 layers
- Burn-In Layer Curing Time: ×3 curing time
- Max Motor Speed: 800
6. Finishing
After printing, clean, dry, and cut your print supports.
- Cleaning Alcohol: Ethyl alcohol (95%)
- Ultrasonic Cleaner or Soak Time: 2 minutes
Note
Do not cure this resin further in a UV oven after printing.