Can overload break osseointegration?

Dear Colleagues,
I would like to share with you a clinical situation and know your thoughts about the possible etiology of the problem.
Mr. X attended my office 5 years ago with a partial edentulism in position 26 and 46.
He suffers from Behcet syndrome, disease that involves inflammation of the blood vessels and which causes sporadic sores in mouth and sex organs and caused his blindness 20 years ago.
He is a friend of the family and asked me to replace these posterior teeth.
He also suffers from bruxism, evidenced by a generalized moderate tooth wear and generalized exostosis of the alveolar bones.
I planned and placed two single implants (Straumann Bone Level, Regular platform) in the free-end positions 26 and 46.
Last week he called complaining of movement on the screw-retained crown on implant 46.
Today, I removed the crown and after retightening it again I realized the implant was slightly painful and mobile. Probing after crown removal was normal. No suppuration was present. Just the normal irritation of the marginal mucosa compatible with the movable crown.
This is the periapical x-ray I took.
Since he was in a hurry, I decided to place a healing cap on the implant and control his evolution in 2 weeks.
What do you think the etiology of the problem could be? Could the occlusal overload have broken the osseointegration of an implant that has been in function and stable for 5 years?
The implant in position 26 is asymptomatic and in function.
I will highly appreciate to hear your comments in such a controversial topic.
Thanks,
Manuel Sancho

01.07.2015, 15:14
Thank you Christoph,
Your knowledge is always of great help.
I will keep you posted with the case's evolution.
Best regards,
Manu
06.07.2015, 08:35
Dear Manu
Overlaod of the peri-implant bone has been documented to occur in experimental studies and there are numerous cases, where overload is a possible etiology of implant loss. In this situation I consider it one of the possible options for the implant mobility, although in a clinical situation it is always difficult to be certain.
Regarding procedural options I agree with Rony that I would take the implant out of function as much as possible and give it some time to rest. If the implant remains free from mobilizing forces and a previous overload was the reason for the current problem, then there is a chance that the implant will become stable again. Thereafter, it is important to really be careful with the magnitude of occlusal and articulating contact on the new reconstruction.
I am interested to hearing more about your therapeutic choices and the future of this implant.
Good luck and best regards
Christoph
05.07.2015, 19:33
It there is really a radiolucency and the implant is mobile than there is no hope and the implant needs to be removed. If you are not sure that I would put a healing abutment on top and leave it for 1 month. Thereafter you can decide wether the implant is lost or not. You know the evidence for overloading an implant is very scare but there are many other options for implant loss.
Best regards Rony
02.07.2015, 05:07
Thanks Rony.
In the X ray there is a light narrow radiolucency surrounding the implant. More evident in the mesial aspect. Since the patient is blind he could not see it but I wonder if any body else agrees that there is something there.
Moreover, when I screwed the crown in, the entire crown-implant complex had a slight movement. The contact point was open. And he felt pain when applying torque to the crown.
I belive the osseointegration is lost and could forsee an explantation in the near future.
What are your thoughts and how would you explain this outcome?
Thanks
01.07.2015, 21:31
Dear Manu Thanks for your clinical problem. According to your description the implant does not have increased probing depths. From a radiographic point of view the Implant does not look that bad. From my point of view in the coronal part of the implant there is a slight bone loss but I would not consider this as loss of osseointegration. Hence, for me it is more a technical complication than I loss of osseointegration. But maybe the resolution of my Rx is not as good as the original Rx.
Thanks and best regards
Rony
01.07.2015, 21:04