April 2019
The patient presented on referral from Dr. MM with a fractured TiBase type abutment in a Straumann 4.8 BL RC implant in the #19 site. The implant was placed on 11.28.2018 and restored on 04.16.2019. After the recovery process was explained, the site was infiltrated with Septocaine, and a very small tissue trim was completed to expose the implant top. The abutment fragment was “wobbled” out and the implant was cleaned. As there was no healing abutment supplied, a small silicone impression plug was placed to help maintain the tissue contours until the appropriate healing abutment can be placed by his restorative dentist. As he has lost confidence in his previous restorative practice, it might be appropriate for Dr. MM to place one for him until he sorts out his restorative choice.
I did explain to him the TiBase design has a very narrow titanium cylinder, and this is the cross section that failed. It is not difficult to understand this mechanism of failure when the size of the crown is examined. Significant torsional loading will occur at the point of the failed titanium cross section when under occlusal function. The pictures below visualize this very well. As this restoration failed very quickly, I would anticipate a similar problem with #18, at some future point, as I suspect they were restored with similar abutments. #18 probably takes more load than #19 due to its posterior position.
