I thought it would be a good exercise to go through an entire implant process documenting a failure of a healthy bicuspid. I also will include a couple tricks at the end on how I dealt with a small issue.
Healthy tooth #4 as taking on standard intraoral photographs and radiograph on routine cleaning appointment
:
One year later, she came in with significant symptoms on the tooth and it was very evident what had occurred:
We treatment planned an extraction and site preservation graft and allowed it to heal for 5 months time. After healing the site was ready for implant planning and placement:
After 3 months of integration we started the restorative process. We scanned with a tibase instead of a scanpost in this particular case and took an xray to verify the seating:
We made a decision to use a multilayer technique on this case instead of screw retained (which would have been possible) because I prefer the ease of delivery of cement retained implant restorations, but I also like having more material options. In this case once we split the restoration and had proper thickness of the veneering structure... there was a problem of the tibase sticking through the abutment.
I left the design as is and milled the abutment out of zirconia and the crown out of e.max HT using EF milling on the 4 motor milling unit:
Once the zirconia abutment was seated, you can see that the parts fit together perfectly
However, when bonding the tibase to the zirconia abutment... the tibase was infact poking through the zirconia abutment just like the design showed and this obviously prevented the parts from seating properly
To correct the issue, you can simply use the abutment as a reduction coping and "flush" the tibase that is sticking through to the zirconia abutment. This should not affect the final restoration if it's just a little bit like in this clinical case
Once complete, everything was delivered in the mouth. Besides the shade being a bit light, the overall process was a success.
I hope this process helps some of you in the tighter interocclusal spaces where you would like to use the multilayer design mode.