Implant Impression in Dentistry
The dental technician then uses the plaster model to produce the appropriate artificial tooth. We distinguish two different techniques:
- the pick-up and
- the repositioning technique
The pick-up technique is the more accurate of the two, but requires more work on the part of the dentist. We want to briefly explain the differences between the two techniques.
In the video "Implant Impression" you see a patient after the completed implantation. The patient was involved in an accident in which her anterior teeth and parts of her jawbone were knocked out. She did not want the lost piece of jawbone to be reconstructed because the red/white aesthetics was not that important to her due to a deep smile line.
Now you see the situation after the removal of the stitches and prior to the taking of the impression – the temporary denture is removed and one can see the gum formers or so-called gingival formers. These caps help the gums heal after the implantation has been performed. The gingival formers must be unscrewed for the impression to be taken.
First, you see the pick-up technique. The respective impression posts are placed on the implant and are screwed tightly to the implant with the so-called wax-up screw. The fit of the impression posts on the implants must be checked closely, because if they don’t fit perfectly, the dental technician will inevitably produce a faulty crown.
Now the impression tray is customized. An opening for the wax-up screw is cut into the tray, because after the hardening of the impression material, the wax-up screw must be loosened from the implant. This is the only way to separate the impression tray (together with the impression posts) from the implant; in this case, two holes were cut. Now you see how the impression tray is filled with the impression material; in addition, impression material is spread around the impression posts with a nozzle. This is to ensure that the posts stick to the impression and don’t move around.
After the impression compound hardens, the wax-up screw can be loosened from the implant thanks to the customized impression tray. The impression (including the impression posts) are removed from the patient’s mouth. So in the pick-up technique, the impression post remains in the impression tray without any handling; in the repositioning technique, it’s different.
Here you see a brief animation about the repositioning technique. The implant is anchored in the jawbone, onto which the impression post is screwed on in the repositioning technique. Since the repositioning post remains in the patient’s mouth when the impression is loosened, the tray does not have to be customized – i.e., the tray doesn’t have to be individualized.
The impression post is only unscrewed from the implant after the removal of the impression tray and then repositioned into the impression tray – hence the name “repositioning impression.” However, the subsequent handling of the impression tray may result in a warped impression. Although the dentist has less work with the repositioning impression, this type of impression-taking technique is more prone to flaws.