Zimmer Dental

Tech Tips  Utilization of Impression Posts

Impression posts are an essential element in restoring any Zimmer Dental implant system. The impression post transfers the position of the implant from the patient to the master cast. Once the impression is recorded and the master cast poured, the selection of the final abutments can be determined.

DESCRIPTION:

Spline Implants

Tapered post with an undercut located coronally, two flat surfaces for indexing. Internal female spline on the seating surface, with a separate retaining screw. Cuff diameters: 4.5mm for the 3.25mm system; 4.5mm and 5.5mm for the 3.75mm and 4.0 mm system; 6.5mm for the 5.0mm system.

Internal Hex Implants

Tapered post with undercuts located coronally, flat surfaces for indexing. Male split hex on the seating surface, with a separate retaining screw. Cuff diameters: 4.5mm and 5.5mm for the 3.5 platform implants; 5.5mm and 6.5 for 4.5mm platform implants; 6.5mm for the 5.7mm platform implants.

Single Stage Implants

AdVent Implant System: Tapered post with undercuts located coronally with a flat surface for indexing. Male hex on seating surface, with a separate retaining screw. Cuff diameter is 4.5mm. Swiss Plus Implant System: Tapered post with undercuts located coronally with a flat surface for indexing. Male octagon on seating surface, with a separate retaining screw. Cuff diameters: 5.2mm and 6.0mm for 4.8 platform implants and 4.6mm for 3.8 platform implants.

External Hex Implants

Taper-Lock Implant System: Tapered post with undercuts located coronally, flat surfaces for indexing. Female hex on the seating surface, with a separate retaining screw. Cuff diameters: 4.5mm and 5.5mm and 6.5mm.

Fixture Mount Packaging

Screw-Vent, Taper-Lock, and Swiss Plus Implant Systems

The Fixture Mount packaged with these implants additionally function as a pre-attached impression post for first-stage transfer impressions. By taking an impression at the time of implant surgery, a provisional restoration may be placed earlier, increasing patient acceptance. The Fixture Mount for Swiss Plus Implants can also be modified

INDICATIONS:

For use in recording an impression when the specific abutment has not been selected.

WARNING

Do not leave impression post in the oral cavity after recording the impression. Do not use the impression post as a temporary abutment.
*Swiss Plus titanium fixture mount/ transfers that are packaged with the implants can be used as abutments for temporary or permanent restorations.

IMPRESSION TECHNIQUES:

(1) Closed tray

A. Remove the temporary gingival cuff using the .050" hex tool.

B. Correctly align the impression post so it interdigitates the restorative table of the implant. Through the center hole of the impression post, slide the .050" hex tool to engage the internal hex of the retaining screw, rotate the hex tool in a clock-wise motion to tighten the screw. Verify with a periapical x-ray that the seating of the impression post is flush with the implant. Block out the hex hole.

C. Record the impression using traditional prosthodontic techniques.

D. Remove the impression tray, unscrew the impression post with the hex drive seating tool, and replace the temporary gingival cuff.

E. Thread the impression post to the implant body analog, making sure the two components seat flush together, looking into the impression for the flat sides, place the impression post and analog assembly into the impression, making sure the assembly snaps into place and is fully seated. Use of a soft tissue cast will represent the soft tissues of the oral cavity.

F. Once the dental stone has fully set, remove the impression tray and the posts from the cast. At this time, abutment choices are finalized and the restoration is fabricated.

(2) Open tray.

A. The Spline impression post is primarily used for indirect or closed tray type impressions. This impression post may also be used in the open tray technique with the purchase of an additional longer retaining screw. Place the impression post onto the implant body ensuring a positive seating and tighten the impression post screw with the 0.50" hex tool. The Screw-Vent Implant impression posts include a long screw for the open tray technique.

Note: A larger access hole can be cut in the stock or custom tray and the occlusal end of the impression posts luted to the impression tray with light cured or repair acrylic. This will prevent the impression post from rotating in the impression once it's removed from the implant body. An addition version of this technique is to secure all the impression posts to the implants, intertwine dental floss around the impression posts and splint them together with light cures or auto-polymerizing resin, then recording the impression.

B. Once the impression material has set, remove the retaining screws with the 0.50." hex tool, and lift the impression tray from the mouth. The impression posts should be incorporated into the impression. Use the 0.50" hex tool to secure the implant body analog to the impression post. A soft tissue cast maybe poured at this time.

D. Once the dental stone has fully set, remove the retaining screws and the impression tray from the cast. At this time, abutment choices are finalized and the restoration is fabricated.