An innovative approach for capturing and measuring patient-specific occlusal information:
- position of the upper jaw,
- inclination of the occlusal plane,
- bite position,
- occlusal surface design,
- tooth set-up,
- lower jaw’s function analysis,
- and its relation to the upper jaw.
For a precise planning security, a comprehensive patient consultation and better communication between patient, dentist, orthodontist and dental technician.
- inaccurate results through facebows or transferbows can be avoided,
- all data can be accurately matched in the articulator by means of reproducible reference planes,
- integration of data for functional analysis carried out by dental professionals,
- articulator with an innovative design,
- completely integrated in the digital workflow.
Reference planes – what’s new?
When detecting the patient’s reproducible Natural Head Position (NHP) by means of the PlaneFinder® measuring/registering device, it is usually possible to localise a horizontal reference plane for the patient‘s skull in the repeatable manner. During the registration, the patient intuitively positions the midline vertically and in the center of the device which allows the user to visualise and record the asymmetries from the patient‘s face on the right and left side of this vertical reference plane.
For information about PlaneSystem® courses please contact:
email@example.com | www.plasterdental.de
An overview of the workflow
Registration of data (in the dental practice)
|Position of the maxilla in the Natural Head Position (NHP):|
With registration material on a (horizontally aligned) tray on the PlaneFinder®.
With the Face Hunter and the PlaneFinder®.
|Inclination of the ala-tragus reference in the Natural Head Position (NHP):|
On both sides with measuring angles on the PlaneFinder® in relation to the horizontal reference plane.
Indication of the relevant anatomical points (Ala nasal/Ala Tragus) on the 3D Face Hunter scan, automatic measuring through the software.
With the jaw registration system PlaneAnalyser (does NOT replace an expert functional analysis carried out by dental technical qualified personnel).
Data transfer into the PS1 articulator (in the dental practice or in the lab)
The captured data are then matched in the PS1 articulator on the basis of the horizontal reference plane.
|Position of the maxilla:|
Alignment of the registration material on the (horizontally positioned) PlanePositioner® on the basis of further parameters (skelatal midline/masticatory centre), insertion of the PlanePositioner® in the PS1 articulator, inserting the maxillary model in the registration material and plastering the model on the upper articulator arm.
Through matching, the model is brought into the correct position in the facial scan with the help of the Transfer Fork (Bite Tray Face Hunter)
Digital data concerning the position of the maxilla can be transferred at any time into the laboratory articulator to carry out manual control steps or working steps. To do so, an occlusal positioning pattern is milled out of the JawPositioner milling blank with one of the Zirkonzahn milling units, and is then placed on the PlanePositioner®, similar to the registration material in the conventional data registration.
|Inclination of the ala tragus line/occlusal plane:|
Display of the occlusal plane (which can have a varying inclination) by adjusting the measured “ala tragus angle” with the help of the two pivoting halves of the table on the PlanePositioner®.
Has already been carried out during data registration
Settings for the PS1 articulator result from the PlaneAnalyser’s measurement log.
Import function in the Zirkonzahn.Modellier software (in preparation).
|The digitisation of the manually captured data is carried out with the S600 ARTI model scanner and the Zirkonzahn.Scan software. Subsequently, they can be combined with patient photos or 3D facial scans (Face Hunter). The entire system can be ideally combined with the model-/patient analyses according to Udo Plaster.|
The third dimension in patient analysis
In clinical practice, incorrectly inclined occlusal planes and functionally inadequate restorations are a common scourge. A possible reason is the often imprecise analysis of patient information. Now Udo Plaster, master dental technician from Nürnberg, has developed a novel transfer approach, the PlaneSystem®.
It determines the occlusal plane and any associated asymmetries individually for each patient based on the ala-tragus plane and natural head position (NHP) and transmits the real position to the CAD/CAM system.
For an uninterrupted digital workflow, the data received and the corresponding coordinates in three-dimensional space must be correctly matched. This can be done with the S600 ARTI structured-light optical scanner and the virtual articulator implemented in the Zirkonzahn modelling software. The scanner acquires the data of the models from the PS1 articulator and transfers them directly to the software’s virtual articulator.
This allows possible compensations to be detected prior to developing a treatment plan for laboratory or chairside restorations, minimising or completely eliminating any sources of error, particularly during data transfer, which might otherwise occur when planning or fabricating a dental restoration.
The next step is the actual modelling of the restoration in the modelling software Zirkonzahn.Modellier. Ideally, the physiognomy of the patient is taken into account during this step. This is now made possible by the Face Hunter 3D facial scanner.
The almost photo-realistic digital face data of the patient can be used either as validity or reference values, but are also ideal for the planning and consultation process between dentist and patient.
Scientific background to the Plaster transfer approach
Scientific studies, e.g. by Xie and coworkers, have identified the connecting line from the lower edge of the nasal wing to the centre of the tragus, the so-called ala-tragus line, to be a more reliable reference for the occlusion line than Camper’s plane or the Frankfurt horizontal plane. The deviation of the ala-tragus plane from the occlusal line is minimal. The ala-tragus line varies from patient to patient, with hemifacial asymmetries a not infrequent occurrence. In order to reliably reproduce the occlusal plane, it is necessary to determine it independently of skeletal class.
The Natural Head Position (NHP)
The second important point of reference within Plaster’s method of transfer is the natural head posture (NHP). A 5-year study by Cooke (2) has shown that patients’ natural head posture varies by only one to two degrees when looking directly into his or her own eyes as they stand upright in front of a mirror. This result is supported by a 15-year study by Peng et al.
The NHP is related to a patient-independent reference frame that allows patient-specific variations in spatial orientation to be reproduced.
Topic-related Studies and Specialist articles
Plaster U. Natürliche Asymmetrien und die patientenindividuelle Wiedergabe der Okklusionsebene ohne traditionellen Transferbogen.
Quintessenz Zahntech 2013;39(5): 1266-1280
Xie J, Zhao Y, Chao Y, Luo W. A cephalometric study on determining the orientation of occlusal plane.
Hua Xi Yi Ke Da Xue Xue Bao. 1993 Dec;24(4): 422-5
Sinobad D, Postic SD. Roentgencraniometric indicators of the position of the occlusal plane in natural and artificial dentitions.
Eur J Prosthodont Restor Dent. 1996 Dec;4(4): 169-74
Cooke MS. Five-year reproducibility of natural head posture:A longitudinal study.
Am J Orthod Dentofacial Orthop 1990; 97: 487-94
Peng, L. Cooke, MS.: Fifteen-year reproducibility of natural head posture: A longitudinal study.
Am J Orthod Dentofacial Orthop 116 (1) 1999: 82-85