Common Operations

• Load the image file
  The [File]-[Open the mandibular raw…] can read a data sets for biGAKU.
• View position
  Buttons of [View Position] button group can change the rendering view position.
• Rotate or translate the image
  Left-click and drag to rotate the image, and the center-click and drag to translate the image.
• Zoom in and zoom out
  Zoom in and out with the scroll wheel.

Surgical Planning [Step1. Mandibular Plane Definition]
As preparation for inputting the reconstruction plan, first determine the “mandibular lower plane” to be the viewpoint reference.

1. Click the [Sel Lower Pts] button of the [Step1. Mandibular Plane Definition] group.
2. Select the [View Potition] button as appropriate and select 4 points from the lower edge of the mandible with the left mouse button double click.
   Please choose 4 points in the clockwise or counterclockwise direction from the lower viewpoint of the mandible.
3. Adjust the plane direction
   You can adjust the direction of the “mandibular lower plane” by manipulating each handle of the plane by dragging the left button.
4. Upward and downward translation of the plane
   Up and down the plane with the scroll wheel.
5. Determine the scan range
   Change the scan range for calculating the evaluation Indicators with the [ScanRange] slider.
6. End definition
   The definition of the “mandibular lower plane” is determined by unchecking [Adjust Position]. Re-check the  [Adjust Position] can turn on the adjust mode.

Surgical Planning [Step2. Cutting Plane Definition]
Determine cuttiing planes to define the cutting area of mandibular. biGAKU distinguishes the area surrounded by multiple cutting planes as an cutting area of mandibular.

1. Check the [Define] box of [Step2. Cutting Plane Definition] group.
2. Select the [Add] and right-click  and drag on the mandibular to add a new cutting plane.
3. Select the [Adjust] to turn on the a plane adjust mode.
4. Closing the mouse cursor to any handler on the cut face can select the cutting plane.
5. Set the direction of the cutting plane
   The yellow arrow from the center of the cut face represents the orientation of the face. [Invert] button can invert the direction of the selected cutting plane.
   Since biGAKU distinguishes an area surrounded by multiple cutting planes as an cutting area, please pay attention to the direction of the cutting plane.
6. Adjust the orientation of the cutting plane
   Left-click and drag the handler of the selected cutting plane can adjust its orientation.
7. Translate the cutting plane
   Translate the selected cutting plane with scroll wheel
8. Add a new cutting plane
   To add a new cutting plane, press the [Add] button again and then according to steps 4 to 7.
9. Delete a cutting plane
   Delete the selected cutting plane with [Delete] button.
10. Finish the cutting plane definition
    After defining all cutting planes, trun off the cutting plane definition mode with uncheck the [Define] box.

Surgical Planning [Step3. Segments Placement]
Define the number of fibular segments and initial placement.

1. Select [2 Seg’s] or [3 Seg’s] of[Step3. Segments Placement] group and press the [initialize] button to switch to segment placement mode.
2. Left double click on the mandibular can define a placement point.
3. The initial position of fibular segments
   fibular segments will be automatically placed if 3 points are assigned at 2 segments mode or 4 points are at 3 segments mode.
4. Clear the placement
   To change the number of segments or cancel the initial placement position, please select the appropriate number of segments again and then press the [initialize] button.
5. Change the opacity
   Change the opacity of the mandibular or fibular segmens with the [Alpha] slider or the [Alpha(Fib)] slider.

Surgical Planning [Step4. Shape Error Calculation]
Start the real time shape error analysis.

1. After the segments placement, you can start real time shape error analysis by pressing the [Realtime Scan] button of the [Step4 Shape Erro Analysis] group.
2. Each evaluation indicator is calculated interactively based on the shape of the preoperative mandibular surface  and the current placement of fibular segments.
3. Display error according to hue circle
   Compared to the preoperative mandibular surface, the degree of dent or Protrudion is expressed from blue to green to red. The more you get green overall, you will see that the shape error is less compared to the original face.
4. Change the threshold of the shape error
   Change the threshold of the shape error with the [MaxTH] slider.

Adjust the placement of segments
Optimize the position of segments while checking the shape indicator calculated interactively.

• Select a section plane of fibular segment
  Select a section plane of fibular segment with double-clicking the center of the square displayed on the section plane.
• Link /Unlink with a cutting plane of mandibular
  You can link the selected section plane with a closest cutting plane of mandibular with the context menu
  [Link to the cutting plane] / [Unlink with the cutting plane].
• Adjust the orientation of the selected section plane
  Right-click and drag to rotate the orientation of the selected section palne (rotate around the eye vector).
• Translate the selected section plane
  Center-click and drag to translate the selected section plane.
• Rotate the segment
  Scroll wheel to rotate the fibular segments with the selected section plane.
• Link / Unlink with the neighbor segment
  In the initial placement of the fibular segments, the section planes of adjacent segments are rotated and translated in conjunction with each other. To cancel this interlocking function, you can turn on or turn off the interlocking function in [Link to the neighbor segment] or [Unlink with the neighbor segment] context menu.
• Adjustment of segment collection position
  Depending on the placement of the fibular segments, biGAKU will automatically determine the segment length of the fibular and the angle of the section plane on the fibular.
  Center-click and drag a segment on the fibular sub-window can adjust its collection position on the fibular.

Analysis tools

• Line segment measurement
  By checking [Lines] of the [Tools] group and right-clicking two points on the mandibular surface, the length of the line segment is measured and displayed.
• Vessel Definition
  By checking [Define Vessel] of the [Tools] group and right-clicking points on the mandibular surface, a vessel line will be defined and displayed on the main screen and sub-screen.

STL Export

• Generate and export a fibular STL
  Press the [Fibular] button of [STL] group to generate and export a fibular STL with the cutting lines.
• Generate and export a mandibular STL
  Press the [Mandibular(pre-op)] button of [STL] group to generate and export a preoperative mandibular STL with the cutting lines.