From exocad documentation
The Bar Module allows the user to fabricate bar-type prostheses ranging from prepared teeth crowns and bridges to implant supported screw retained or custom abutments. This module allows multiple bar shapes in an arch and customizeable bar profiles. It also includes the ability for attachment placement and retention pillars.
To begin, the dental database must be correctly completed. The Bar pillars  indicate where the abutments/implants are located, the Bar segments  are the connectors between the pillars.
You can move the control points (the small balls) by dragging them with the left mouse button. You can also drag the arrows for restricted movement in one direction.
|Control+Click||Add Control Point|
|Drag Point + Right click||Remove control point|
|Shift+Drag||Move point and it's neighbors|
|Control+Drag||Move point and it's further neighbors|
|Control+Shift+Drag||Move ALL points (using insertion plane)|
|Click on arrow||Toggle automatic placement of control point. Hold <Shift>, <Ctrl> or both to extend toggle-range.|
Choosing the profile
When the bar design screen is open, a profile selection window will show.
Select the desired profile from the Type  drop-down box.
By default, the newly selected profile will be applied to the entire bar. By selecting the Apply to selection radio button, you can apply new profile choices only to the currently selected bar segment (marked by purple with yellow outlines). To select a specific segment, simply click on it. You can change profile parameters by unfolding the Profile Parameters expander.
Once the initial steps have been completed and you have reached the Wizard window Bar Design the Profiles window will appear. In the Profiles window you will see the Select profile section. Here you can choose the Type  of bar profile from the pulldown. In the Profile parameters  pulldown you can adjust many sections of the bar in various ways to suit your desired shape. If this shape is one that you would like to use again, you can click Save . This save will allow you to rename your new bar profile and it will be accessible in the Type  pulldown for future use. To access this click Folder . The Options  section will allow you to apply a particular profile to a selection or segment of the bar or to the whole bar. If you made a mistake you can re-apply the profile.
If you would like to create a custom profile please see: Extending the bar profile library
Wizard: Bar Design
Here you will see 3 tabs: PROFILE, ADVANCED and ATT. (Attachments).
In the PROFILE tab there are many features:
Bars and Pillars : Adjustment of bar and pillars simultaneously.
Bar only : Adjustment of the bar only.
Pillars : Adjustment of the pillars.
Borders : Adjustment of the borders only.
 This allows you to preview the result of your changes made to the prosthesis.
 This box, once checked, allows you to use borders around the implants. This is to accommodate extra space of the papilla around the implant/tooth.
 This box, once checked, allows you to use the advanced profile editing. See section advanced profile editing.
Auxiliary Planes: Show planes  section:
Insertion Axis: Use plane  section: Insertion axis of the secondary frame that will fit over the bar. This axis can be changed by a view dependent setting of the model or can be viewed by having the check box checked.
Define  : this drop down will allow you to
Set From View [11} Rotate the model to a desired position for your Path of Insertion, then click this button.
In the ADVANCED tab, there are other features:
Switch to Round/Edgy Design : Adjustment of edgy or rounded profile of the bar.
Distance to Gingiva(mm) : Distance slider in (mm)...... If you check the Crop  checkbox......... If you check the Pull-down  checkbox then......
Auto Level : This maintains the height (size) of the bar after it has been adapted to the gingiva, as to avoid dips in the contour height or an unlevel surface of the top of the bar.
Min. Pillar Angle ( Above Orange Line )  : Angle slider in degrees.
Reset to Default : Pillars and Bar : You have the option to work on just the pillars or just the bar.
In the ATTachment tab, the following features are available:
Add : Add an attachment selection from the drop down list.
Library : Select a name from the drop down list.
Type : Select a file type from the drop down list.
Apply to Last Selected Part :
Snap to Gingiva : Left-clicking this tab will make the attachment adjust to the tissue surface.
Rotate : This effects the rotational movement around the pivot point of an attachment. "Free" allows total freedom of movement in all directions. "Top" restricts the movement to orbital rotation on top of the bar. "View" is setting the rotation to the current view that you have moved the model ( Bar ) to on the screen. ( similar to a path of insertion in C & B )
Set Docking Point : Center is the midpoint/center of the attachment preview (left click to apply dot); H is the height / X is the horizontal axis direction / Y is the occlusal axis direction.
Creating custom profiles
To create your own profile, you can use one of the already available profiles as template and change the parameters to reflect the desired shape. Then, click on Save.
To create profiles that are more radically different from the already available profiles, see section Extending the bar profile library below.
Planes help you during bar design. They serve as a reference, and can define the insertion axis. There are two planes:
- The reference plane (green): This plane is typically used to define the top of the bar.
- The auxiliary plane (yellow): This plane is parallel to the reference plane, but positioned at the height of the currently selected control point. It helps you to see easily what the height difference between the currently selected control point and the reference plane is.
You can change the inclination of the planes by dragging the green ball on top of the control arrow in the center of the plane. You can move the height of the reference plane to height of a specific control point by double-clicking the control point (in other words - double-click the selected control point to reposition the green plane to exact position of the yellow plane).
Here you can make the planes visible by having the checkbox checked.There also is the Define plane pulldown: Here you are able to reset the plane or click to define a plane by three points and a height offset. In this case, a new window appears called Auxiliary planes.
Using the control points
Control points can be snapped to each other (to keep them parallel to the reference plane), or to the reference plane itself (when the plane is visible).
By default, each control point can be moved independently of it's neighbors:
By clicking one of the cyan arrows, which point to it's neighbors, you can link the height of a control point to it's neighbor:
The fact that two control points have their height linked to each other is indicated by a dark blue color of the arrow. The segment between the control points is now parallel to the auxilary plane.
By clicking one of the green arrows, you can snap the respective control point to the reference plane. Note that this is only possible if the auxilary plane visualization is enabled.
If the control point is snapped to the plane, it will feature a green halo.
Setting the insertion axis of the bar
By default, the insertion axis of the bar is orthogonal to the reference plane. If you change the plane inclination, this will also change the bar insertion axis.
If this is undesired for a particular design, uncheck the Use plane checkbox in the Insertion axis box within the first tab. Then, rotate the view so that you look onto the design from your desired insertion angle and click Set from view. The new insertion axis will be visualized by a blue arrow.
The effect of the insertion axis on pillar shape
By default, pillars will have a cylindrical shape and follow the axis of the implant. You can change this by setting a margin on the pillar that separates the pillar into two parts: one part follows the implant axis, the other part follows the insertion axis (meaning that it is blocked out).
To add this control line:
The image below illustrates how this affects the shape of the pillar.
Left: Cylindrical shape (default).
Right: Orange control line inserted by <Ctrl+Shift+Click> - the part above the orange line is now blocked out following the insertion axis (shown in green in the image).
Extending the bar profile library
In addition to the XML-based parametric shape definitions in the shipped .barProfile files under DentalCADApp\library\bar, the bar profile library may also be extended using STL files, if the meshes meet certain characteristics.
The orientation of the meshs must be as follows:
- Occlusal direction: Y
- Direction of the bar: Z
- Lingual direction: X
- Recommended triangle edge length: 10µm
Proceed as follows:
- Click the "Open Directory" icon .
- Select "*.stl;*.off;*.obj;*.sdfa;*.csfda" in the file type selection drop-down , then click "Open".
- In the message box that pops up, chose if you wish to have the profile fixed or user-changable.
- Inspect the resulting bar. If results are not satisfactory, work on the STL (e.g. use different export settings in the software that generated it, change orientation, etc) and try again.
- To save the profile in .barProfile format, click the "Save" icon .
Designing superstructures over bars
Once your bar is finished and produced, you can design a superstructure:
- Set up a new case with the indications that go on top of the bar, and select "Substructure (e.g. bar)" under "Implant based?" in DentalDB, as shown in the image below.
Note: If you do not see that option, contact your reseller or the provider of your material configuration file. The option is available as of 2016 Version of exocad DentalCAD (as beta).
- Scan the finished bar, and proceed to "Design" again. Follow wizard instructions for the superstructure design.
Why re-scan model with bar, as a new case?
Some customers would prefer to design everything digitally in one go. We do not recommend this at this point. For various reasons, the milled result of a complex shape will always be slightly different than the original design - depending on milling strategy, tools, manual post-processing such as polishing/removing supports, etc. Some milling centers may manage a "full digital" process for selected bar shapes, but generally, re-scanning is the safer path to good results. In case of simple shapes such as abutments, the software can predict quite well how the final result will look - which is why the exocad Implant Module support designing everything in one go for abutments. For complex bars, it's a different situation.