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Using Photogrammetry to Validate the Accuracy of the Medit i500

Photogammetry has set the highest standard for full arch accuracy in digital dentistry for edentulous patients with multiple implant fixtures. An easy scan in under 15 seconds captures enough detail on scanbodies that help the software capture the location of the fixtures. Conversely, Intra-Oral Scanners (IOS) do not garner support for most of the literature that is currently published in dental journals.  Scan paths can dictate the outcome of 3D model and determine how correctly it replicates the intra-oral condition. The same scan can render a variety of results and models based on the user and the direction the scans are taken. Simply stated, the user is control over the final product.

To use the ICam 4D scanner you must first calibrate the machine with a plate immediately prior to the intra-oral scan capture.  There are specific reference points that the camera and software recognizes and after you capture about a dozen landmarks, you are ready for an intra-oral scan

Calibration of the ICam 4D Photogammetry  Machine

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calibrate icam 4D

 

After the camera is calibrated, the patient, or in this demonstration case, the model with Multi-Unit Abutment analogs is mounted with ICam Reference Bodies that are shaped like dominos.  They can attach to the multiunit abutment or directly to the implant fixture (available soon in the USA).

 

The markers are captured by the device in the software with multiple identification marks, ideally 10 marks on each scan post.  This data is then exported as an stl file that has all the locations of each cylinder preserved.  This whole process just takes minutes.  Most people just utilize this device for full arch impressions so they can bypass the verification jig for large cases.  Here, we use it to assess the accuracy of the medit i500 ios to provide cross arch accuracy if doctors follow our protocols for imaging, which utilizes the reliability map as a guide for imaging.  When then utilize the Artificial Intelligent Implant Suprastructure Identification Software to merge and evaluate the accuracy of the ios scan.

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measure implant icam scanbodies
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save the implant scanbody cyliners and their coordinates

There are a lot of ways one can introduce errors into a full arch scan with any ios, but the medit’s powerful features that include the reliability map and the AI tool separate it from all other scans that do not allow you to assess the accuracy of your scan while you are imaging.  You can only do so with the fabrication of a verification jig

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Medit's AI feature merges the IOS model with the photogammtry produced model