Application Guide for Separated Models Long-Term Materials
Subtype: Teeth Separated
Resin: QuraCROWN LT
Software: Alpha 3D
Denture Teeth Design
When designing your denture, one important distinction is how you cut the teeth portion from the base. Two main ways that the base and teeth can be cut are as follows:
A. Separated: Each tooth is designed individually and exported as a separate STL. This design is usually far superior in terms of part fit, appearance, and future repairability. However, it takes more time to design and print initially.
B. Conjoined: All teeth are joined together with some material. This method is much easier to design and print. However, this design is vulnerable to part distortion from UV curing, and may leave unsightly gaps from the base. Additionally, if any part of this model breaks, the entire model must be reprinted and refitted.
This guide shows how to print separated teeth models.
1. Print Analysis
With denture teeth, there is no concern about comfort to the user, so the fitting area is not very important. So it is better to put the emphasis on the aesthetic portion of the tooth.
A. Critical Areas – Do Not Support
- You can safely avoid supporting all of the area that would be above the base. This means, the entire visible area of the tooth does not need supports.
B. Intended Support Area
- The bottoms of the teeth, where they would be set into the base, are the ideal place to put the supports. In general, you do not need to have supports much higher than the bottom 25% of the teeth.
A. Position the print as vertically as possible, with the fitting area of the tooth facing downwards.
Depending on your design software, the bottom may be rounded, so it may be hard to make the bottom flat. It does not need to be perfect; your goal is to just make the sides of the tooth not require supports.
B. Raise the part off the platform.
- In Alpha 3D, you raise a part along with setting up its supports. Go to the Supports tab, and set the height in the parameters.
- Support Height: 1.5 – 2.0 mm
When supporting this print, Ackuretta recommends doing the following:
- A. Set up the support parameters shown to the right.
- B. Use Auto Support to add the majority of the supports.
- C. Go to Manual Support, and use the slice slider to find the lowest points of the model. Make sure that supports are on those points. If multiple supports are very close together, you can remove redundant supports, as long as at least one is on the lowest point.
- D. Add more supports along the bottom of the teeth to make sure that they are strongly affixed to the build platform.
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.
- If you use the General support setting, Alpha 3D automatically adds a small base to every support. This small base is sufficient for most prints.
- Additionally, you can add a base around the entire print using the Base Thickness setting. This makes it easier to remove the print from the build platform.
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.
Arrange all of the models that you want to print, and then go to the Print tab.
- Select your Layer Thickness. Ackuretta recommends 70 microns.
- Give your print a Job Name.
- Click Save.
On your printer, make sure that your settings match what you need for your resin.
Diplo / Ackuray Print Settings
- Buffer Layers: 5 layers
- First Layer Curing: ×8
FreeShape 120 Settings
- Burn-In Layers: 4 layers
- Burn-In Layer Curing Time: ×4 curing time
- Z-Axis Peel Speed: 900
After printing, clean, dry, and cut your print supports.
- Cleaning Alcohol: Ethyl alcohol (95%)
- Ultrasonic Cleaner or Soak Time: 2 minutes
Then, use a toothbrush to brush away white particles.
Post-cure the prints in a UV oven.
- UV Oven Specs: 365nm wavelength or lower, with at least 16W power intensity
- UV Oven Time: 45-50 minutes in a 16W oven. Time can be shorter with higher-power ovens
Finally, polish your prints using a standard polishing kit.
- Grit: Medium to fine grit, 90 grit and above