VR-based 3D Tooth Operation Model System for Dental Surgery

Demo

Demonstration of operations of each tooth through 10 transformations!

Demonstration for the whole teeth by calculating the transform matrix!

Abstract

Advisor: Prof. Bin Sheng, Institute of Computer Application, SJTU

• Proposed and Implemented a method for relocating the center, initially equal to the center of the whole teeth, of each tooth, established single tooth coordinate systems and oriented bounding boxes (OBB) for each tooth by using principal component analysis (PCA)
• Implemented interactions with 10 forms of transformation for each tooth with keyboard and mouse:
  • Rotate around X/Y/Z axis of the tooth
  • Pan along X/Y/Z axis
  • Rotate around left/right/top/bottom side
• Established scenes of operation for data displaying and transplanted the PC interactions to VR interactions for simulating the operation of dental surgery, implemented the calculation of transform matrix for each tooth

Implementation

• Import initial model Convert the .stl file to .obj and load them into the project
• Relocate the center of each tooth Calculate the mean of all vertex coordinates of each tooth but the coordinate axis is still the world space axis.
• Transform the world space axis to the self one. Calculate 3 vectors under the premise of using the teeth as a cuboid
  • v1(z-axis): from root to top
  • v2: from lingual side to lip side
  • v3(x-axis): v1 x v2
  • y-axis: v1 x v3
• Calculate OBB and generate the final model
• 10 forms of transformation