Printing Strategy for Separated Models
with 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. The three methods for printing the teeth are as follows:
A. Separated: Each tooth is designed individually and exported as a separate STL file. This method usually creates the best fit, appearance, and future repairability. However, it takes more time to design and prepare the print.
B. Conjoined: All teeth are joined together with some material. This method is much easier to design and print. However, it is vulnerable to distortion caused by UV curing, and can cause unsightly gaps between the denture teeth and denture base. Additionally, if any part of this print breaks, the entire object must be printed and fitted again.
C. Grouped: Combine the teeth to form a bridge. This method has the same advantages as the Separated and Conjoined methods.
This document shows how to print separated denture teeth.
1. Print Analysis
There is less concern about comfort to the user because the denture teeth are securely attached to the denture base. The occlusal surfaces are more important than the fitting area. Therefore, it is better to put the emphasis on the aesthetics of the tooth.
A. Critical Areas – Do Not Add Supports
- It is not necessary to put supports on any areas that are above the base. Therefore, the entire visible area of the teeth do not need supports.
B. Intended Support Area
- If you are printing the teeth as Separated or Cojoined teeth, the fitting area is the best place to put the supports. In general, you do not need to put supports any higher than the bottom 25% of the teeth.
- If you are printing the teeth as a Grouped teeth, you can add supports to the buccal, labial, or lingual sides so that the occlusal and fitting areas remain smooth.
A. Put the model in as much of a vertical position 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 difficult to make the bottom flat. It does not need to be perfect; your goal is to make the sides of the tooth not require supports.
B. Raise the model off the build platform.
- You can automatically raise the model when you add the supports. Open the Supports panel and use the arrows to set the Support Height.
- Support Height: 1.5 – 2.0 mm
When adding supports to the model, we recommend the following procedure:
- Open the Supports panel, apply the settings as shown below, and click the Auto Support button to add supports.
- Click the Manual Support button and remove any supports that are too close together.
- Add supports to any areas that have too few supports.
- Add more manual supports to the lowest points of the print to make sure that area is securely attached to the build platform.
You must select an object to add supports to that specific model. You cannot use the Auto Supports or Manual Support functions with all models at the same time.
Use the View Slider function to identify the lowest points of the print.
We strongly recommend adding a base to your model because it allows the print to securely attach to the build platform. A base also makes the print easier to remove during processing.
- If you use select General on the Type dropdown list, Alpha 3D automatically adds a small base to every support. These small bases are sufficient for most prints.
- You can also key in a value for the Base Thickness setting to add a base around the entire print. This makes it easier to remove the print from the build platform.
A thicker base does not improve print performance. A Base Thickness of 0.400 mm or thicker can make a print less likely to succeed.
When all of the models that you want to print are in place, click the Printing Setup button to open the Printing Setup window.
Make sure the settings are as follows:
- Your printer is selected on the Printer Model dropdown list.
- QuraCROWN LT is selected on the Material dropdown list.
- The Layer Thickness is set. We recommend a layer thickness of 70 micrometres.
Click the Print button to open the Print window and save your model as a print file. The top of the window shows your Printing Setup settings.
- Key in a Job Name.
- Click the Save button to save the name and settings.
Alpha 3D slices the model into layers and creates the print file. When the process is complete, it shows the IBF file in a window. You can now send this IBF file to your printer and start the printing process.
When the printing process is complete, you must clean, dry, and remove the print supports.
- Cleaning Alcohol: Ethyl alcohol (95%)
- Ultrasonic Cleaner or Soak Time: 2 minutes
The best use of the UV oven for post-curing is as follows:
- 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
Use wire cutters, scissors, or a rotary tool to carefully remove the supports. Start cutting the supports that are farther from the print, and then cut closer when it is easier to manage.
Grind away any remaining support marks. Use a brush to remove excess material and residue from the surface.
Finally, polish your prints using a standard polishing kit.
- Grit: Medium to fine grit (i.e. 90 grit and above).