Heavy bone loss around implants in grinder: feedback?

The only treatment in medicine that always works, is removing the cause. The fit of these crowns is a "killer" for the bone. We are talking about the marginal seal. I mean that even if the margin looks closed on the X-Ray but it has gaps more than 10 microns. Temporary cementation is also an issue. Have ever smelled a crown that was cemented with temporary cement even for two weeks? It smells horrible. 100 years ago surgeons didn't wash their hands and didn't wear gloves while operating. Patients were dieing and no one understood why. The only solution to achieve the proper marginal fit is start taking direct impressions without using transfers or impression copings. Such technique requires tissue management around the abutment. I mean gingival retraction using G-Cuff. It also allows easy splinting these 3 crowns especially if the patient is a bruxer.

The main problem in this case is the marginal fit. Once the crowns fit well and there is no gap there won't be a bone loss. Sometimes the misfit is so small that it can't be seen on the X-ray but the damage to the bone can be as significant. The solution is taking impression directly without transfers.

The cusps on the two opposing premolars are a big factor since these stick down below the occlusal plane and allowed the pt to during bruxing to overload these two implants (distal implant little bone loss as no opposing tooth) occlusal plane should have been corrected before the implants were restored. also look at the 2012 PA the crestal bone isnt very dense lets see a PA of the implants when restored

With all due respect, when one restores something i.e. an old automobile or house we attempt to return it to its original condition. When we restore a patient, we should attempt to do the same. This case was not a restoration, these are simply implants and crowns. Looking at the occlusal plane one can see a deep curve of Spee as well as super-eruption of the opposing dentition. The patient is a bruxer and exhibits para-function. Part of the treatment plan in a case such as this is to address these findings in order to ensure success and/or reduce the risk of failure. I am assuming the patient paid close to $15,000 for this treatment. They deserve our best efforts. This is an occlusal rehabilitation case. To restore these implants and place them under the most ideal loads should be the goal.

I'm curious how the teeth were originally lost. This looks like peri-implantitis and it appears the implants are below the plane of occlusion with the opposing maxillary premolars out of occlusion. This is what untreated peri-implantitis looks like. It appears that the tipped supraerupted molar is holding the vertical can't really tell since the patient is not in full occlusion on the panorex.

First I would like to make my self clear. I don't want to criticize but rather to analyze the case in order to understand it better. Implant failure has always two factors. The biological factor and the bio-mechanical one. From the mechanical point of view besides the option of splinting the crowns there was a room to put longer implants. CBCT treatment planning and guided surgery gives the dentist more confidence to work with longer implants. From the biological point of view, besides the marginal fit that may cause the significant bone loss, the fact that implant fixtures left sometimes for years on a temporary cement, can be the main reason for such a failure. Temporary cementation has advantage of retrievability in implants, but it has also a high price. Implant abutment cannot suffer from decay, however when the organic filer is washed away it is replaced by bacteria and inflammation.

Are these NobelDirect implants?

I have placed approximately 7000 implants over the last 32 years. Most of them were done before guided surgery existed. Guided surgery is not the reason those implants are too short, nor is it the reason the margins are open. The reason is lack of surgical and prosthetic skill. The problem with guided surgery is that it does not allow the dentist to develop any surgical technique. As far as the occlusal scheme goes, once again the majority of implants I placed were patchwork. Very few of the patients were restored to ideal occlusion with full mouth reconstruction yet I have cases that have been in function for over 30 years. Finally I was the expert witness on a case in which 4 implants were never restored. No occlusion, no bruxism, no open margins and the bone simply dissolved around them. Sometimes stuff (I was thinking of a different word actually) happens. I am going to post a full arch case in which the bone is disappearing. It is screw retained, and fits beautifully. There is no evidence of bruxing. Health history is non-contributory. I cant wait to hear the suggestions.

Dr Levitt, your comments are spot on. The issues here are bruxing and a nonidealized occlusion, not open margins.

"The problem with guided surgery is that it does not allow the dentist to develop any surgical technique." Have someone heard about semi-guided surgery or parallel surgical guide. SG Parallel Surgical Guide - HIDENTECH ?