Bellus3D Dental Pro iOS and Dental Pro Web Alignment Options

Bellus3D Dental Pro iOS and Dental Pro Web Alignment Options

Options for Aligning 3D Face Models with Dental Jaw Models


Background

The integration of 3D face models with upper and lower jaw models to create a digital virtual patient has become a powerful tool for patient motivation and face-based design for dental planning. One of the challenges in creating this virtual patient is that the face model and jaw models are independently captured by two different types of 3D scanners that have no correlation to each other. 



Intraoral Jaw Model shown with Face Model Before and After to Alignment


Establishing a correct spatial relationship between the two models is a process of model alignment. Within the Bellus3D dental apps the face and jaw model alignment is accomplished by the repositioning of the face model in 3D space relative to the selected jaw models. This is important to note because the user interface of our apps show alignment adjustments as movements of jaw models which we implemented to make for a simpler user interface within the app.  It is also important to note that the spatial alignment relationship that is established between the face model and the selected jaw models is only valid for those models. If the face model is to be used with another set of jaw models a new alignment will need to be established. 


Bellus3D offers multiple methods to align 3D face models to jaw models that accommodate different use cases, available equipment and required precision.  This document enumerates the currently available options.

General Recommendations and Overview

There are three options for aligning a Bellus3D face model with jaw models that are presented in this document. 


  • Dental Pro for iOS
    Dental Pro for Apple iOS is an all encompassing app that enables 3D face scanning and alignment of the 3D face model with jaw models. This is best for a dental clinic where the staff and technicians will capture the 3D face models and perform the alignment with jaw models for patient motivation or in-clinic dental planning. Dental Pro for iOS is compatible with Apple iPhone (10,11, 12) and iPad Pro devices that incorporate the Apple True Depth/Face ID camera.
    https://bellus3d.com/dental/

  • Dental Pro Web
    Dental Pro Web is a web app for viewing 3D face models and aligning those models with jaw models. It is best used where the dental planning workflow is PC based. Dental Pro Web can view 3D face models 
    which were scanned with Dental Pro iOS devices or with the Bellus3D ARC1, ARC4 or ARC7 camera system. A Dental Pro user account is required to use Dental Pro Web. The app can view and perform alignment of face models that have been uploaded from the same Dental Pro account that was used for scanning or from an account of a different user who has uploaded and shared a face model with the Dental Pro Web user.  fc.bellus3d.com.

  • ARC4 and ARC7 Bite Plate Enhancement Feature
    A bite plate is a small surface with 3D patterns that is adhered to the front of a bite fork that is placed in a patient's mouth for use as a common reference area when aligning face models, jaw models or CBCT models. Users of the ARC4 and ARC7  camera systems can enable a “Bite Plate Enhancement Feature” within the Bellus3D ARC scanning app which increases edge detail of the bite plate within the resulting face model. The enhancement feature is used to assist the use of 3-point alignment tools that are available in 3Shape Dental System, Anatomage, exocad, Dolphin Imaging, and other dental planning software.
    Information on the ARC Camera System:
    https://bellus3d.com/arc

1. Dental Pro for iOS

The Dental Pro for iOS app can be used to capture and view a 3D face model and align the face model to a set of imported jaw models. The jaw models can originate from any intraoral or dental lab scanner and must be in either an .stl or .ply file format. Dental Pro uses the concept of a Workspace to contain the 3D face model, jaw models and smile design guides.  The models used in the Workspace are selected in the Workspace Creation screen as shown below.



Jaw Models and Face Model selected for a new workspace


To integrate the 3D face model with the 3D jaw model, an opening needs to be cut out of the 3D face model shell to reveal jaw models. This opening is called a lip line cut out.




Upon initiation of a face and jaw model alignment, Dental Pro for iOS software will automatically perform a lip line cutout.  To visualize the interactive adjustment to the alignment of the two models, a two panel view is presented overlaying the 3D jaw models with the 2D photos of the face presented in comparable pose orientations.




Adjustments to the alignment can then be controlled by using the Translate and Rotation "+" and "-" buttons presented on the bottom portion of the screen in the Adjust tool tab of the app as shown below. 



Translation tools will move the appearance of the jaw models left and right (red axis), up and down (blue axis) or in and out (green axis). In the example show below in Overlay Fig1, the transparent-colored overlay of the teeth in the jaw models is lower than the teeth shown in the photo. By repeatedly pressing the "+" button of the blue axis the jaw model moves higher to align with the incisal edge of the photo of the teeth. 



See the video below to see how to cycle through using the horizontal transparency slider to view the 2D photos versus the jaw model. A good adjustment strategy is to horizontally align the midline of the front teeth first using the translation adjustments along the red axis, then adjust the vertical translation of the incisal edge along the blue axis, and then pivot and tilt the jaw model as appropriate using the rotation controls as needed. The rotation controls pivot and tilt the appearance of the jaw model anchoring on the incisal edge and midline planes. The adjustment process requires iteration and you need to move between the translate, rotation and transparency controls until you reach a final result. A good alignment is achieved when the translucent jaw model overlay thinly outlines the front facing photo of the teeth in the right side panel. 





Once a satisfactory adjustment has been made between the face and jaw models, the resulting aligned face model can be exported from the Tools tab by tapping on the down arrow export icon. Aligned face models can be exported as a .obj, .ply or .stl file for subsequent use in dental planning software. 





2. Dental Pro Web

Dental Pro Web is a web-based application that enables viewing, exporting and alignment of 3D face models to jaw models within a web browser. Dental Pro Web is not a scanning app. Some dental practitioners prefer to delegate the alignment of face models with jaw models to the lab or prefer to operate the adjustment work on a computer.  The face models shown in the gallery screen of the app are models originating from the user's own Dental Pro iOS account or models the user has upload from using a Bellus3D ARC Camera App. Face models in the gallery can also be models that have been shared by other Dental Pro accounts. 





To align a face model with jaw models in Dental Pro Web the user selects the upper and lower jaw models to be aligned, adjusts the lip line cutout as needed and uses on-screen controls to align the face model with the jaw models. Dental Pro Web provides automatic alignment of face models to jaw models and provides editing tools to adjust the alignment as needed. In order for alignment to work correctly, the input jaw models must be oriented with the incisal edge parallel to the x-axis.  See our Knowledge Base article  "Supported Jaw Model Orientation Face Scan Alignment" for more information.

While the Dental Pro Web adjustment controls are similar to Dental Pro iOS, the controls are not exactly the same. The basic steps start with the New Workspace creation page and the selection of the upper and lower jaw models as well as the face model. Pressing the Next icon in the upper right part of the screen will create the Workspace.



It is recommended that you preview and adjust the lip line cutout to reflect a natural open area of the mouth. Select the Lip Line menu item in vertal menu on the right side of the screen. The ideal lip line cut out follows the contour of the lips at the visual intersection where the teeth begin. Select and individually move the circular lip line markers as needed before saving your result.




Prior to making adjustments to the alignment of the jaw models to the face model, we recommend hiding the visibility of the lower jaw model in order to simplify the view of the overlay. Within the Models pane, click on the eye icon to the left of Lower Jaw to hide the lower jaw model visibility.




Dental Pro Web presents a singular front view of the alignment pane. The first recommended step for adjusting the alignment is refining the position of the Z-Axis if needed. Adjustments to the alignment in the Z-axis move the appearance of the jaw files inward or outward relative to the face mode. Turn the face model to a left profile view with a slight tilt up and use the "O" and "P" keyboard keys or on-screen keys to move the jaw model forward or backward along the Z-axis. Move the jaw model until the front face of the upper teeth meet the inside opening of the upper lip at the teeth contact point shown below.



Once the Z-Axis is aligned, use the Translation and Rotation Tools in the same manner as indicated previously for Dental Pro iOS. The on-screen adjustment controls map to keyboard keys in a cross pattern on the keyboard. Try using the keyboard keys as a faster method for controlling the adjustment. 



The above screen shows the jaw model positioned lower than photo of teeth. Use the up arrow button to adjust the vertical alignment. When you are ready to export the aligned face, select the Models tool menu and then the export icon. Note - it is best to export the face model with the lip line cut out activated as indicated by the slash through the smile icon.



 

3. ARC Models with Dental Bite Plate


The Bellus3D ARC4 and ARC7 cameras enable the use of the Bellus3D Dental Bite plate enhancement feature. The .stl file of the bite plate can be downloaded from with the ARC scanning app and printed on a 3D printer. The bite plate needs to be attached to a bite fork for placement in the mouth. During normal scanning the ARC scanning software performs smoothing and maps any external objects such as eyeglasses or bite plates as part of the face. 


Edges of Bite Plate shown as a result of automatic applied smoothing


By selecting the “Enable Dental bite plate feature” in the ARC 4 or ARC7 scanning settings of the Bellus3D ARC Scan App (see screen below) , the app will detect the presence of the Bellus3D bite plate in the face model and substitute the smoothed bite plate front surface in the model with a sharp well-defined surface to provide more precise points for 3 - point alignment in dental planning software.


Dental Bite Plate Setting Dialog from the Bellus3D ARC Scan App Settings Menu



Bite Plate edge enhancement applied
The Bite Plate enhancement provides sharp edges to the rendering of the bite plate within the scan enabling the required precision needed to perform 3-Point alignment in dental planning software.
    • Related Articles

    • 3Shape Communicate Integrated with Dental Pro for iOS

      The current version of Dental Pro for iOS allows you to align a face model with teeth models that are stored in your 3Shape Communicate account. If you want more indepth information on how to use 3Shape Communicate with Bellus3D Dental Pro, please ...
    • Getting Help with Dental Pro

      When reporting an error or problem to Bellus3D using Dental Pro please provide all of the following information to enable us to understand and respond to you quickly: Provide us with the name and model of the iOS device you are using: (iPhone X, Xs, ...
    • Bellus3D Dental Pro app for iPad and iPhone Overview

      Bellus3D Dental Pro is a new dental app for Apple iPad Pro and iPhone X. The app can work with Bellus3D Dental services that you can purchase through an in-app monthly subscription.  Go to Settings in Dental Pro to see your options.  Dental Pro uses ...
    • Dental Pro for iPad - First Time Use

      To use the advanced features, you would need an advanced subscription which you can purchase in Dental Pro.  Tap the gear icon on the home page to get to Settings then tap Upgrade to Advanced to see your options.   Here are some suggestions for using ...
    • Access and load your STL/PLY teeth or CBCT scans into the Dental Pro app

      In order to select your own files for alignment, you will need an Advanced subscription.  You can purchase advanced in app.  Tapp the gear icon on the home page then tap Upgrade to Advanced in the Settings page to see your options.    ------------- ...