CEREC SCREW-RETAINED IMPLANT PROVISIONALS

11 years ago

Contributed by Dr. Farhad Boltchi

There has been some discussion recently on how to fabricate screw-retained implant provisionals. Obviously there are several different ways to do this and hopefully in the near future we will have a TelioCad or Lava Ultimate or Enamic mesoblock, which will make this process easier. In the meantime I am posting below the 2 methods that I use in my office:

1.) Glidewell Biotemp: Using a Glidewell scanbody to scan with the Cerec, upload to Glidewell via Connect for a screw-retained Biotemp (slides below). Very quick and efficient method and very cost effective ($76 for Biotemp including shipping + $15 for scanbody, which can be re-used).

Problem is that Glidewell's quality is very inconsistent. In the slide below you can see 3 consecutive Glidewell temps. The first one is undercontoured, the second one is overcontoured, and the third one is the correct contour.

Another problem is that the Glidewell Tibase has one flat side but not any retentive elements and so there can be a debond between the temp and the tibase, especially if Glidewell uses their 3mm tibase instead of their 6mm tibase (which they sometimes do for no rhyme or reason). In the slide you can see a comparison between the Glidewell tibase and a retentive Straumann temporary abutment/tibase.

2.) My preferred method is to fabricate the temp indirectly after an implant-level impression. This method is more labor intensive but is also more predictable in terms of contours and soft tissue development: Implant level impression, lab wax-up with ideal contours on implant model, scan wax-up as Biocopy, scan retentive temporary abutment on model and mill Lava Ultimate temp, bond to temporary abutment for screw-retained temp.

The beauty of this method is that the ideal contours of the wax-up serve as the guide for the screw-retained temp, the abutment, and the final restoration, which all follow the same contours. The wax-up gets scanned in once as a BioCopy and that is used in the design and fabrication of all restorative components. The soft tissue gets developed ideally and the abutment and final restoration follow that contour and fall into place perfectly without any releasing incisions, etc. (see the second case below).