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| The Ackermann Clip
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| A bar clip attachment that allows free movement of the prosthesis. Its applications are for overdentures and implant prosthetics. The principle feature of the Ackermann Clip is that the bar may be adjusted to follow not only the vertical contours of the mucosa, but also the anterior-posterior curvature of the edentulous ridge. The spacer provides for both vertical and rotational free movement of the prosthesis. The clip is fully adjustable and easy to insert and remove. | |
| Wide field of applications, as the bar may be bent in all directions allowing it to exactly follow the contours of the ridge (FIG 1). | 1 |
| The Ackerman may be used for
square or curved arches. Due to its short 3.6mm length, the sleeve may be positioned on the bar even in a deep narrow trough (FIG 1). |
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| No soldering of the clip.
The horizontal retention tangs (FIG 2-3)
provide firm retention in acrylic and require no additional vertical space.
Firm yet resilient support of the prosthesis assured by the elasticity of the riders. Spacer provides for free vertical movement. Easy path of insertion and removal. The ackermann clip fits the Round Bar, the Hader Bar, and the small Dolder Bar. The shape of the bar is indicated by the amount of room available, by the shape of the alveolar ridge, and the type of construction.
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| Technique |
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| 1. Prepare the abutment teeth in a normal manner. The bar can be soldered, cast, or laser welded to fit abutment crowns, root cap copings, or implant abutments. | |
| 2. Try in all cast restorations. |
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| 3. Try-in set-up. | |
| 4. Make a plaster matrix of set-up. | |
| 5. Ensure that there is sufficient clearance between the bar and the mucosa so that the extensions of the clips can move freely without impinging on the alveolar tissue (FIG 4). | |
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| 6. Wax out the undercut
area beneath the bar on the model and relieve the areas where the retention
sleeves will be placed (FIG 5).
7. Duplicate and cast model. Place the clips in the desired position on the model after having cut away the plaster very slightly in these positions to avoid opening up the clips too much (FIG 6). The sleeve is then raised to its highest position and held there by the insertion of a piece of the special half-round spacer (FIG 7a-b). |
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8. Place the clips in position. Block out their ends as show in (FIG 8a-b). With the aid of the plaster matrix, set up teeth and process on the model. |
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| The ackermann clips firmly retained in the prosthesis (FIG 9). | 9 |
| 9. After periods of use, it may be necessary to further activate the sleeves by pressing them inwards with an instrument (FIG 10). | 10 |
T0044.REV.00
