3D Printed Teeth

In NSW Universities are now using 3D printing to replicate decaying in teeth for students to practice operating on before going into the surgery to work on the real thing.

The University approached Cammpro to see if they could help by 3D printing teeth with multiple materials to replicate the hard-outside enamel and the soft decaying material on the inside.

Decay in actual teeth are made up of an outside enamel which is the hardest substance in the body which is made from crystal rods, decay eats through a small section of enamel until it reaches the softer dentine layer directly underneath, once the decay reaches the softer dentine it is able to spread out more easily as the substance isn’t as resistant. The decay is a lot softer than the enamel.

Below is a cross section of a real decayed tooth:

1

3D print request from the university was:

3D print a tooth that can be used in university trials so the students can Insert a pointed instrument into the hole, lever to and fro to break the enamel away that overlies the decayed lesion. Remove the “simulated decay” with a hand instrument:

2

leaving the underlying healthy dentine, then fill the cavity with restorative material.

Initial concept by Cammpro:

Simple tooth model:

Cross section                             Cross section with decay

3 4

The above model could be 3D printing using the technology call polyjet 3D printing, the Connex 350 polyjet 3D printer has the capability to print multi materials in one print, and also has the capability to 3D print a range of soft rubber like materials, the range of applicable shore hardness available is below:

6

Therefore with the help of 3D scanning and polyjet 3D printing the teeth could be manufactured.

Firstly the tooth model that is currently used at the uni was 3D scanned using the Einscan 2X plus to create the CAD model in STEP format:

7

This model was then imported into Autodesk inventor 3D CAD software to start the design of the decay, with decaying hole in the enamel:

8

Now the decay can be 3D Designed into the tooth:

9

 

Now a 2 part file, known as an assembly can be saved and exported to an STL file to be 3D printed with two separate materials.

The finished product now looks like this:

10 11

 

 

 

 

 

 

 

See the video here:

https://www.youtube.com/watch?v=0cXiBMpgMoE

https://www.youtube.com/watch?v=buYxJGSxFhw

Feedback from the university:

  1. The printing quality was amazing
  2. The form / shape of the tooth was accurate
  3. The fit of the tooth into the model was ideal
  4. The fit of the tooth in the dental arch and next to the other teeth was ideal
  5. The decayed lesion was perfectly accurate
  6. The simulated (printed) healthy enamel and dentine withstood scraping pressure from the dental spoon excavator hand instrument (the tactile feedback was near identical to the ‘real thing’)
  7. The decay in the 1mm thickness scooped out with the right consistency and quantity.
  8. The 3D printed tooth functions well and better than anything that we have used in the past

A very happy customer.

Contact us with any of your design queries, no job to big or to small


gavin