One of the most common complications with cement-retained implant restorations is inflammation around the implant crown. Excess cement can cause peri-implant diseases, including peri-implant mucositis and bone loss.
One of the most important aspects to understand is the biological differences between teeth and implants, specifically related to the junctional epithelium and connective tissue, which results in the difficulty of removing the cement around the restoration.
This step-by-step visual essay shows how to fabricate a silicone jig to control the cement around an implant-retained restoration.
Figure 1: Frontal view of a screw-retained implant supported provisional restoration on a maxillary lateral incisor.Figure 2: Frontal view of the peri-implant soft tissue architecture after maturation.Figure 3: Occlusal view of the peri-implant soft tissue. Note the adequate thickness of the buccal soft tissue.Figure 4: Zirconia abutment on the master cast.Figure 5: Layered zirconia crown on the master cast.Figure 6: Zirconia abutment cemented to Variobase and layered zirconia crown designed for cementation.Figure 7: Zirconia abutment secured to the implant and screw torqued to manufacturer's recommendation.Figure 8: Zirconia abutment in place. Note the margin is accessible for cleaning after cementation.Figure 9: Teflon tape is packed in the space between the abutment and the soft tissue.Figure 10: A double Teflon cord technique is used by placing two different cords in the shape of a letter “C” to avoid any exertion of cement to the apical region.Figure 11: Screw access is obliterated with Teflon tape (plumber's tape).Figure 12: Using a fine tip, silicone material (Gingifast) is injected inside the crown. A fast-setting impression material, or bite registration silicone, can also be used.Figure 13: View of the result after the silicone material completely sets.Figure 14: Cement is injected inside the crown depending on the case and the clinician's choice of using temporary or permanent cement.Figure 15: The crown with the cement is repositioned in the silicone jig and all excess cement is removed with a microbrush.Figure 16: Internal view of the crown with a minimal cement layer.Figure 17: After cementation, the Teflon tapes are removed, and any excess cement will be attached to the tape.Figure 18: Final view after cementation.Figure 19: A final radiograph is taken to confirm the correct adaptation of the crown and assure there is no excess cement.
This is a simple, step-by-step technique to fabricate a silicone jig to avoid excess cement for a cement-retained implant supported restoration. This technique can be applied to a single crown or to an implant-supported cement-retained bridge.
Ricardo Mitrani, D.D.S., M.S.D., is a member of Spear Resident Faculty.
References
Wadhwani C, Pineyro A. Technique for controlling the cement for an implant crown. Journal of Prosthetic Dentistry. 2009;102(1):57-58.
Present S, Levine RA. Techniques to control or avoid cement around implant-retained restorations. Compendium of Continuing Education in Dentistry. 2013;34(6):432-437.
