1. As soon as you start simulating, the Progressive transition button is available at the right bottom. Select it to start with the comparison process.
   Observe that the “Before” 3D disappears from the screen and only the “After” 3D is visible. 
   The transition slide is also available. The bottom of the bar represents the Before and the top represents the After.
2. Select the slide and drag it upwards -or downwards- to see a progression of the change.
   Observe that the label at the bottom of the 3D model will indicate if you are viewing the Before, the After, or halfway.
3. If you prefer to see a straight transition, without the crossfade effect, select Crossfade at the top of the transition slide.
4. To exit the comparison mode, select the Progressive Transition button one more time. 

This procedure assumes that you have created at least 2 simulations.

1. On the simulator, select Open Simulations at the top right to open the page with all the saved simulations for that patient.
2. Select, with a maximum of four, the simulations you want to compare against the Before 3D, and select Open at the bottom right.
   The simulator's screen is divided to present the Before 3D at the left and all the selected saved simulations are on the right part of the screen.
3. Observe that the Progressive transitionbutton is enabled at the bottom right. Select to open it.
4. Select the slide and drag it upwards -or downwards- to see a progression of the change.
   Observe that the label at the bottom of the 3D model will indicate if you are viewing the Before, the After, or the name of any of the saved simulations.
5. If you prefer to see a straight transition, without the crossfade effect, select Crossfade at the top of the transition slide.
6. To exit the comparison mode, select the Progressive Transition button one more time.