Perform Analysis


 

Select the lateral cephalogram designated for the simulation and an appropriate lateral photo from the album view of the patient's images.  It is also possible to select the cephalogram only and load the photo from within the simulation screen later.

Simulation of different treatment procedures requires the specification of bony and/or dental regions whose position changes during treatment.  There are several ways for defining regions.  You may manually draw region or create them by means of pre-defined templates, that can be manually adjusted and cut.  In addition wizards for creating the regions and performing the simulation are available.

 

 

Create Region from Templates

 

zauberstab

If treatment planning is effected by means of a lateral cephalogram the [Regions Wizard] button allows creating the regions out of pre-defined templates by the help of a wizard.  This button is only available for defining regions in lateral cephalograms.

 

 

Create New Region

 

Region_neu  

The [Create New Main Region] button allows manual drawing of regions.  The item Region1 appears in the Region field.  By a mouse click on this item the region may be named as the desired.

 

freihandregion

With active [Freehand] button, draw the shape of the region by dragging the mouse within the initial image with left mouse-down.

 

konturregion

Alternatively to drawing the [Template] button allows selecting of pre-defined regions.

 

 

Correct/Supplement Region

 

Add_Region Subtract_Region  

If necessary, correct or supplement the region's form by means of the buttons [Add Region] or [Subtract Region].

 

 

Split Region

 

Schnittfuehrung  

Any region can be split into two subordinate regions, which can be independently displaced and rotated.  Select the region to be split in the Region field. Thereupon it is highlighted in the initial image.  Activate the [Incision] button and mark the initial point of the cut by a mouse click on its position in the initial finding.  Then drag the mouse with left mouse-down to the final point of the cut.  After confirming the query the cut will be displayed in the initial finding.  At the same time two subordinate items will be displayed below the selected region in the Region field at the right margin of the form.  By clicking on that items you can type the names of the segments.  Correcting the cut can be done by dragging the endpoints to the desired position.

The subordinate regions resulting from splitting can be split again.  Owing to that fact and to the possibility to group partial regions even complex cuts can be simulated.

By the [Delete Incision] button the subordinate parts of an superior region can be merged again.  At this the focus has to be on the superior region in the tree structure.

 

 

Move Region

 

versch_hori   versch_verti  

For simulating the several steps of the treatment the selected regions are displaced or rotated.  The result of the simulation is visualized and can be controlled by means of graphic collision control and numeric specification of displacement and rotation of each area.

Select the region to be displaced in the field Region by a left mouse click.  Click on the subordinate region if only this segment is to be moved.  Selecting a region is also possible by a mouse click in the initial finding.

 

If you want to displace several regions as one piece, further regions can be added to the first region.  For that purpose the additional regions are selected by a right mouse click.  Thereupon all selected regions are highlighted by a blue background and are also accentuated in the result field.

Displace the region by the help of the arrow buttons in horizontal or vertical direction.  The displacement takes places with relation to the image coordinates.  Displacing a region can also be done directly in the result field by mouse drag-&-drop.

 

 

Anfang_Linie   entlang_linie Ende_Linie

It is also possible to move a region along or perpendicular to a defined line; e.g. tooth along its axis.  Selection of the initial point and the endpoint of this line is done by the help of the buttons [Direction].  A left mouse click in the initial finding while the button is activated captures the landmark that is situated closest to the cursor position.  By right mouse clicks the points can be freely positioned in the initial finding.  Displacing the region along the line or perpendicular to it is done by the help of the buttons [Move Region].

 

 

Drehen   Rot_Zentrum

In addition the selected region can be rotated by the relevant [Rotate] buttons to the direction requested. Thereby the center of rotation, which first of all is situated in the calculated center of the selected region, can be displaced by the help of the button [Center of Rotation] and a mouse click on the relevant position in the field of the initial finding.  The amount of displacement and rotation is displayed below the button bar.

 

 

Monitor Displacement

 

Punkt1 Punkt2 Punkt3

If there are defined landmarks within the selected region, the landmarks having been displaced to the greatest amount in general, in horizontal and in vertical direction and the landmark having been rotated to the greatest amount are displayed in the Maxima field of the Points tab.

In the evaluation field the displacement of specific points within the selected region or the change of lines and angles between points within and out of the region can be read.  After activating the 3 [Landmarks] buttons landmarks can be selected from the lists or arbitrary points can be marked by mouse click in the initial finding.  A left mouse click captures the landmark that is situated closest to the cursor position whereas the point can be freely positioned by a right mouse click.

In the table below the displacement and rotation of each of the points is displayed and the values of all angles and lines between them before and after treatment are calculated.

 

 

Calculate Soft Tissue Reaction

 

The soft tissue does not follow the bony displacement during orthodontic treatment or orthognathic surgery to the same extend. For calculation of the prospective soft tissue profile the relations between bony displacement and resulting soft tissue changes have to be considered.

 

The calculation of a new soft tissue line can be optionally deactivated.  In this case no automatic prediction of the soft tissue profile is offered.  The soft tissue line may, however, be modified by moving the soft tissue landmarks to the desired position.

 

If the resulting soft tissue profile is to be automatically calculated, this can be done by means of regulations that deterministically calculate the soft tissue reaction from the bony displacement by quasi-linear regression models.  The standard regulation comprises a number of definitions that calculate the vectorial shift of single soft tissue landmarks based on the displacement of one ore several bony points.  The standard regulation may be modified and saved as individual regulation.

 

Another possibility for soft tissue prognosis is the Finite Elements method that assumes linear-elastic behavior of the deformed soft tissue.  This can be seen as an approximation of the actual soft tissue behavior that depends on age, gender and further factors in reality.  

 

In the right result window the position of single landmarks can be manually corrected.  For this purpose, select the landmark to be corrected by a left mouse click on its marker within the result image and drag it to the new position with left mouse-down.  The amount of displacement can be read from the Adjust Soft Tissue Line field of the Soft Tissue tab.  The buttons [Reset Landmark or Landmarks] right of the display of the landmark displaced set the last landmark or all landmarks to their originally calculated position.

 

For photo-realistic illustration of the prospective treatment results the initial photo can be morphed to the new calculated profile by the button [Calculate].  This merely serves visualization purposes and aims at illustration of the tendency of treatment-caused changes of the dento-facial area.

 

If treatment to be simulated is mere surgical without movement of single teeth the Osteotomy Wizards that are called via the respective buttons can be used.  They automatically create the regions to be displaced and subsequently move them to the desired position.  After that, however, individual adjustment is possible.

 

For the following standard operations wizards are available

 

 

Icon Buttons

icon_bsso

Bilateral Sagittale Split Osteotomy

icon_lefort

Le Fort I Osteotomy

icon_bimax

Bimaxillary Osteotomy

icon_kinn

Genioplasty

 

 

icon_bsso Bilateral Sagittal Split Osteotomy:

 

The mandibular region including the first molar, the first premolar and the central incisor is marked and split into a proximal and a distal segment by a pre-defined cut.

 

BSSO_1

automatically drawn and segmented mandibular region

 

After that the distal segment is put in correct relationship to the maxilla.  That means that at first the lower central incisor is correctly placed against the upper central incisor according to the overbite and overjet set in the preview dialog.  Then the entire distal segment of the mandible is rotated around the fixed lower incisal edge until the lower molar touches the occlusal surface of the upper molar.

 

BSSO_2

automatically shifted and rotated distal segment

 

After finishing the planning of the bilateral sagittal split osteotomy it has to be decided if an additional correction of the chin is necessary.  The simulation of a genioplasty is also supported by a wizard that can be started following any other osteotomy.

 

The wizard merely simulates the bony displacement during a bilateral sagittal split osteotomy.  After that the simulation of soft tissue changes can be carried out.

 

 

 

icon_lefort Le Fort | Osteotomy:

 

The maxillary and mandibular regions including the first molars, the first premolars and the central incisors are marked.

 

LeFort_1

automatically drawn maxillary and mandibular regions

 

After that the maxilla is put in correct relationship to the mandible. That means that at first the upper central incisor is correctly placed against the upper central incisor according to the overbite and overjet set in the preview dialog. Then the entire maxilla is rotated around the fixed upper incisal edge until the upper molar touches the occlusal surface of the lower molar.

 

In this position maxilla and mandible are fixed together and rotated as complex until the upper incisor reaches the relation to the upper lip set in the preview dialog. The rotation point is in the center of the condyle.

 

LeFort_2

automatically displaced and rotated maxillary and mandibular segments

 

After finishing the planning of the Le Fort I osteotomy it has to be decided if an additional correction of the chin is necessary. The simulation of a genioplasty is also supported by a wizard that can be started following any other osteotomy.

 

The wizard merely simulates the bony displacement during a Le Fort I osteotomy. After that the simulation of soft tissue changes can be carried out.

 

 

icon_bimax Bimaxillary Surgery:

 

The maxillary and mandibular regions including the first molars, the first premolars and the central incisors are marked. In addition the mandible is split into a proximal and a distal segment by a pre-defined cut.

 

Bimax_1

automatically drawn regions

 

First of all the maxilla is correctly placed  with regard to the sagittal position, dental exposition and inclination of the occlusal plane set in the preview dialog.

 

After that the distal segment is put in correct relationship to the maxilla. That means that at first the lower central incisor is correctly placed against the upper central incisor according to the overbite and overjet set in the preview dialog. Then the entire distal segment of the mandible is rotated around the fixed lower incisal edge until the lower molar touches the occlusal surface of the upper molar.

 

BiMax_2

automatically displaced and rotated segments

 

After finishing the planning of the bimaxillary osteotomy it has to be decided if an additional correction of the chin is necessary. The simulation of a genioplasty is also supported by a wizard that can be started following any other osteotomy.

 

The wizard merely simulates the bony displacement during a bimaxillary osteotomy. After that the simulation of soft tissue changes can be carried out.

 

 

icon_kinn Genioplasty:

 

The mandibular region including the first molar, the first premolar and the central incisor is marked and split into a proximal segment and the region of the chin by a pre-defined cut.

 

Kinn_1

automatically drawn and split mandibular region

 

In the wizard several methods can be selected that include different standards for the harmony of the chin. Owing to the fact that the soft tissue of the chin follows the displacement of the bony chin to the same extend the chin is displaced to the amount of the difference between norm value and measured value of the deciding variable of the selected method. That means that the chin will be correctly positioned after the soft tissue simulation.

 

By means of a subsequent change of the inclination of the cut and another start of the wizard a slight correction in the vertical plane is possible in addition to the shift in sagittal direction.

 

Kinn_2

automatically displaced chin region

 

The simulation of a genioplasty can be carried out separately or following any other osteotomies supported by wizards.

 

The wizard merely simulates the bony displacement during a genioplasty. After that the simulation of soft tissue changes can be carried out.