Below here the Toltac® protocol for data acquisition is described in detail. It is a very easy and intuitive procedure, but it must be followed step by step in order to plan correctly. A PDF of the Toltac® surgical protocol is available for free on the 'procedures' page.
1. Diagnostic template.
The diagnostic template must include a structure allowing the template positioning between the dental arches and radioopaque references preferably far to one another and positioned on different levels; it is very important that they are positioned so that during the CBCT scanning they remain completely separate from the projection of the patient's dental arches, in order to prevent scattering effects coming from prosthetic or conservative components of the dental arches.
NOTE. Some softwares allow matching between CBCT and model scanning even without the use of a diagnostic template, although its presence during CBCT is an additional guarantee of accuracy.
2. Relining the diagnostic template
Apply a little amount of elastomere impression material on both surfaces of the diagnostic template, carefully preventing contacts of the elastomere with the radioopaque elements of the template.
If in the Dental Office is available a CBCT machine it is preferable to take the CBCT scan to the patient asking him to keep in the mouth the just relined diagnostic template, and remove it only after the CBCT. If the patient is sent to a radiologist, he must carry the relined diagnostic template. The radiologist must be carefully check the correct positioning of the template during the exam.
Please remind the patient to bring back the template for the scannings (see below).
Relined diagnostic template
3. CBCT exam
The CBCT can be done in standard resolution, with a FOV wide enough to include all the bone structures of the studied arch and all the radioopaque parts of the diagnostic template. The radiologist will provide a set of axial DICOM images with 512x512 matrix for the data upload to the virtual planning software.
4. Impressions and creation of plaster models
Best if taken with precision elastomer impression materials, but also good alginate impression are OK. The plaster models are obtained from the impressions with the normal procedure. Preferably make models with an abundant base, better if with the incision of a few niches in order to make easier the matching when uploading the scans to the planning softwares. If an optical scanner is used, it is recommended to extend the scan to the soft tissue as far as possible to allow for an optimal template design. If possible, impressions with an optical scanner should be avoided in the case of extensive edentulias.
scan of a model with nicks
5. Diagnostic wax up
The missing elements of the arch to treat must be replaced with a normal diagnostic wax up, unless it is available a software able to provide a virtual diagnostic wax up from the model scan.
6. Scan of the models
For a correct planning, are needed the following scans:
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edentulous model
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edentulous model with diagnostic template
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model with antagonist arch
IMPORTANT. When using an intraoral scanner, the scan of the diagnostic template must be made in the mouth, keeping it well adherent to the arch to be treated, and all radioopaque references and as many anatomical structures as possible must be carefully scanned to facilitate matching with the scan of the arch without the template.
edentulous model
template on the model
model with diagnostic wax up
Axial DICOM images from CBCT with 512 x 512 matrix and the three scans above mentioned are the informations that compulsorily must be obtained; unless these informations it is impossible to proceed to the planning according theToltac® protocol.