Placement of library teeth

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The simple mode

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The software loads the library teeth and places them automatically using the previously defined preparation margin. With single indications teeth are placed following automatic detection of the adjacent teeth or by clicking on the adjacent teeth with complicated jaw scans. In the same step there is the option of optimising the placement of the model teeth manually by moving, rotating and scaling. Switch between these modes using buttons [1-3]. Then, simply drag and drop the mouse on the teeth to make your adjustments.

TipNote that the tooth models are displayed in yellow – this means that they are responsive to mouse clicks. Whenever objects are displayed in yellow in the viewer, they will react to clicking and/or dragging the mouse.

For crown preparations, don't be overly worried about positioning accuracy at this point – a rough placement will be enough; you can always do fine-tweaking later in the „Freeforming“ step. It doesn't matter if the model tooth doesn't properly fit the preparation (see [7] for an example) – as long as the tooth model is positioned somewhat reasonably in relation to the preparation, the software will adapt the library tooth automatically in the next step.

For inlay preparations, accurate positioning is crucial already at this point. The closer you position the model tooth to the prepared tooth, the better the result will be, so it is worth to invest a little time here.

TipA semi-transparent display of the model teeth might help you see both the prepared tooth and the model tooth, thus facilitating accurate placement. Right-click on „Anatomic shapes“ in the „Show/Hide groups“ window to toggle transparency for all library teeth – for details, see the „Showing/hiding objects in the viewer“ section.

A light red color (for example [6]) marks an area where the tooth model is placed so close to the preparation that it lies within the material's minimum thickness. The software will automatically fill these areas during the adaptation of the tooth models. So, in the area marked by [6], once the tooth is adapted to the preparation, the fissure will not be as deep as in the original model tooth, due to the restriction enforced by the minimum material thickness.

HotkeyInstead of using the mouse for switching between modes [1-3], you can also leave button [1] pressed and use hotkeys to quickly toggle modes – this will save you a lot of time : Hold <CTRL> to switch to rotation, <SHIFT> to switch to scaling. Note that whenever hotkeys are available, they will be displayed in a „tool tip“ for the respective button. So, in this case, you can simply move the mouse over button [1], and a help bubble will appear which reminds you of the available hotkeys.

Use the right-hand menu bar “Distance to the antagonists” to visualise the distance (or the intersections). An antagonist visualisation window appears and intersections with opposing teeth are highlighted in colour in the design. Also refer to the section “Visualisation of the intersections / distance to the antagonists or adjacent teeth”.

Restricting movements

In some cases, it may be useful to restrict possible movements to certain directions. Especially novice users who are not yet used to navigation in virtual 3D space will appreciate the options [4] which allows you to limit movements/scaling only to:

  • Mesial/distal direction only
  • Buccal/lingual direction only
  • Occlusal direction („up and down“) only
  • Mesial/distal and buccal/lingual direction only („move to all sides, but keep height“)

Moving all teeth simultaneously

You can move all teeth simultaneously by checking checkbox [5]. This is useful e.g. when all teeth are positioned too low or too high in the software's initial set-up suggestion. When done with the adjustments, click 'Next' to proceed to the next step. The model teeth will then be adapted to the preparations.

The chain mode

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Selecting the “Chain mode” [6] tab activates linking of the teeth. This linking enables the teeth to be moved splinted together without losing proximal contact points or creating penetration areas. The maxillary teeth chain moves independently of the mandibular teeth chain. Penetrations by the antagonists are not automatically prevented by this but must be created or removed by the user.

There is a control point in front of each tooth while the “Chain mode” is active. If the point is green, the tooth is integrated in the chain. By clicking on the control point of a tooth it changes to red and the chain is deactivated. Teeth highlighted red are no longer influenced by movement of the chain and can thus be used as a type of anchor. This allows teeth to be fixed in their position while the other teeth can be further aligned.

The chain mode has three subfunctions:

  1. "Chain" [7]
    If this function is activated, all teeth that are active (green control points) can be moved in the same way as a pearl necklace.
    During movement, the teeth are automatically kept in contact and scaled in size, if required.
    Tip This function is recommended to place the library teeth in their approximate position.
  2. "Individual" [8]
    The “Individual” function enables an individual tooth to be moved, rotated or scaled in the chain, without the action having a direct effect on the adjacent teeth.
    Tip The “Individual” function is suitable for correcting the position and axis alignment of individual teeth.!!!
  3. "Tube" [9]
    The “Tube” function allows the teeth to be moved along the visualised chain as if on rails.
    Tip The entire set-up can be moved using the “Tube” function, e.g. to align or slightly adjust the midline.!!!

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The “Symmetry” button [10] enables tooth positions to be transferred from one quadrant to the opposite quadrant.

To cater for different situations the symmetry button is divided into four subbuttons, each of which forms a corner of the symmetry button. The subbuttons can be used for selecting which quadrant should be used as the basis for the transfer and whether a full quadrant or only the anterior teeth should be transferred. The different symmetry modes are shown using a plane and a direction arrow.

If the option is activated, all corrections of one quadrant are immediately transferred to another quadrant.

The symmetry function is deactivated again by re-clicking the symmetry button.