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To Cement or Screw your implant crown?

Updated: Jan 8, 2023

Hi everyone and welcome back to another blog post. Today we will be discussing cement versus screw retention, a hot topic that has gone back and forth in implant dentistry.


In my practice, I prefer to use screw retention in most cases of single units and use a custom abutment to control the emergence profile that we have created or customized as seen in our previous blog posts (LINK HERE)


Although ti-bases can be commonly used instead of a custom abutment, I believe that in the posterior zone of the mouth, they are often too small to withstand the occlusion and stress of the area. Cost factors often limit the use of custom abutments for many practitioners although I do believe that custom abutments are better in the long term.


custom abutment on a full contour screw retained zirconia crown

The picture below shows a classic fracture of ti-bases , although the crowns are screw retained, the short height of ti-bases and unsupported zirconia can shear off.

So should you cement or screw retain your cases? well i think it DEPENDS ! for more than a single unit, the passivity of case can be more difficult to achieve. This is where I believe the use of custom abutments shines. Implants have an internal connection that allows for what we call an anti-rotation feature of the crown, this also takes the pressure off the screw only to hold the crown in the right alignment.


By using a combination of custom abutments and cement retention we can get the best of both worlds. In essence, custom abutments are placed on to the implants. The bridge is then placed over top with screw channels if we ever wish to access the screw channels later. The cement space ensures passivity of bridge over the custom abutments.

Custom abutments for two unit splinted restoration

In the photo above, you can see that one custom abutment is pre-bonded. This custom abutment can be either hexed or non hexed, the other abutment will be placed intraorally and splinted restoration to go over top. Please ensure that you are relieving the area of excess cement by making a duplicate of the crown interior with PVS to pump excess cement extra-orally prior to intra-oral cementation (see this LINK for explanation) The use of the custom abutment will also ensure that your cement does not get subgingivally into the implant connection which is another reason why I prefer them over a small ti-base.


If you enjoyed this post and this discussion let us know !


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The current cement-in system that we all learned in dental school, exposes your patients to open, overhanging and overextended margins and subgingival cement. Do you know why? Well the bad margins result from the same root cause as the misfit joints related to the screw-in system. Its called Prosthesis Dimensional Error (PDE) and a Tissue Effect called Resitence to Displacement.

The subgingival cement is largely caused by the Gingival Effects, where the tissue facing surface of the crown pushes against the adjacent gingiva, forms a seal and blocks the egress of excess cement from the tissues spaces ... and the dentist pushing the crown into place thus pressurizes and forces the excess cement deep into the tissues. So if y…

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To Cement-in or Screw-in your implant prosthetics is a BIG question. The answer lies in what is better for the patient and how you are Screwing-in or Cementing-in your prosthetics. Research results tell us both systems are associated with a similar and troubling rate of peri-implant disease. It also tells us that plaque, misfit joints and poor prosthesis margins and subgingival cement are risk factors for disease.

The current screw-in system most likely causes misfits for single teeth and misfits for sure for multiple teeth restorations. Cantilevers for screw access can make the peri-implant environment difficult to access and maintain and do increase loads on misfit joints. This is well documented stuff and I can tell you why it happens…

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