3mm of Crestal Bone Loss: What Should I Do?

I am not there is occlusal overloading. The opposing dentition is a removable partial denture

With all due respect, I wish to differ ... It would be a reasonable assessment to make that in this case the bone loss was rather rapid. Microbial peri-implant infection usually will not lead to such a rapid progression of bone loss. Occlusal overload is usually the culprit with rapid bone loss. Especially, if we have insufficient bony crest peri-implant bone morphology (insufficient bone width) and inappropriate implant design and over-submerged vertical implant placement, in combination with occlusal disease and/or unfavorable crown-to-root ratio. Peri-implant mucositis is a possible precursor to peri-implantitis. One must also take into consideration a possible peri-implantitis due to lack of an aseptic technique during implant surgery. And another possible contributing factor is if this patient is a smoker. Also, we have observed that in many earlier implants placed on ridges with insufficient keratinized attached gingiva ... there is almost never a problem as long as the hygiene is reasonably good. In conditions of poor oral hygiene, any quality of tissue, whether it is attached or non-attached, keratinized or non-keratinized, the scenario for developing a possible peri-mucositis are similar, although the case with keratinized attached tissue will have a better chance to protect the underlying bony tissue, hence, the peri-implantitis is less likely, and if it were to occur, it is a slow process. This case will eventually fail, and, at best, it will be in survival mode with constant peri-implant suppuration, simply because this case is plagued with possibly many errors in diagnosis and treatment planning.

In addition, the point I wish to emphasize is that the microbial involvement is only secondary to the existence of appropriate initial condition(s) that led to a rapid bone loss and peri-implant soft tissue pocket formation, thus setting up ideal conditions for a peri-implant mucositis and peri-implantitis. Thank you.

One further comment ... my hygienist is making the remark that if this was such a uniquely a hygiene/plaque problem that caused this issue, then why are we even placing implants in such a case? And, what is more, our colleague reports that there are implants in quad 3 with no problem ... is the hygiene so significantly different from one quad to the other that it would be the only reason to explain rapid bone loss ? Let's think about this properly.

It don't think this case is plagued with lots of clinical errors- thats over stepping the mark sir be constructive not offensive.

To the Colleagues on this thread: I wish to apologize if any of you have felt offended by my remarks. But, in my own defense, I wish to state that it was not my intention to offend any of my colleagues here. But, I will offer this additional commentary, if I may ... I base my commentary solely on the information given initially. Let us, first, at least, agree to disagree. Although I cannot be 100% certain, my guess based on disclosed information is that the problem was initiated very likely by an occlusal overload situation. Look at the neighboring teeth 45 and 44. There would appear to be severely worn cusps, and, a disto-buccal restoration on 45 that was likely a non-carious cervical lesion, possibly abfraction, caused by occlusal disease, possibly, but not with absolute certainty, after all, this is a 70-year-old patient. Look at the possibility of a lateral tongue thrust habit or just simply an enlarged tongue due to long-standing absence of the natural molars in the area. On 2 splinted crowns, this may not present a problem, but on a single implant/crown with a compromised crown/root ratio, it is potentially a problem due to compromising lateral forces on the bone. And, in response to the commentary made to me by colleague TOBooth: I am quite aware of the literature that has been written over the past many years. Perhaps, we can discuss the abundance of debate that has led to no conclusive evidence about whether keratinized attached gingiva is really necessary around teeth or implants. Please do not misunderstand, I personally prefer the keratinized attached gingiva and it's potential benefits, no question. In the present case, we are not given any information about peri-implant pocket depths. On the given radiographic image, I see bone loss with both a horizontal and vertical component. Also, is it possible that we do not need a huge amount of keratinized attached gingiva around the molar implants ... after all, most of the natural molars I have seen in my long career usually have minimal amounts in the lower molars, naturally. I will also agree that a peri-implantitis caused by excess cement is a possibility, and I apologize for this omission. Also, I think I know the difference between peri-mucositis and peri-implantitis. If this "acute periodontal abcess", as it was called by mistake initially, occured, it had to start with bacterial invasion in the peri-implant sulcus ... peri-mucositis, an inflammatory condition not involving bone, will start, which may lead to peri-implantitis, bone destruction. With my knowledge and experience, I do not intend to be arrogant with my suggestions ... I do not have time for such action; I intend to offer diagnostic possibilities. And, I stated that this case is possibly plagued with errors in diagnosis and treatment planning ... I don't think this commentary is an insult to anyone, and it should not be, it was not intended as such. It was intended to stir a debate about diagnosis, since our colleague has challenged us with such an interesting situation. May God Bless

good point.

Bull-he has just said there has been pus!!! thats not normal!

I agree with this comment. I have stated this in my earlier remarks as a possible contributing issue.

I think you hit the diagnosis on the head Dr. Berne! Bonus points to you. Not just implants, cement left in the sulcus can and will eventually eat into crestal bone around tooth-borne crowns as well. Me thinks the cemented crown margin was too sub-gingival and maybe there was a piece of cement on the buccal that caused this issue. I think this implant has a fair prognosis with proper care.

Gingival fibers don't attach to the smooth surface of titanium either (exception being Biohorizon's implants with the very specific horizontal laser grooves solely for CT and epithelial attachment) That said, I think you hit it right on the head - crown margin is too subgingival and when it's that subgingival, it makes it impossible to remove all the excess cement. Also this implant is not platform switch, so you're expected to lose 1.2mm of bone, the 1st year in function right off the bat.

Yes, the point is that the implant is oversubmerged, and the first threads are really far from the initial crest of bone at implant placement, I suspect.

It isn't though!! So would you leave threads exposed ???!!! Plus you can't augment vertically!! So this implant isn'rt too deep.

The most coronal threads, according to the image presented, appear more subcrestal than necessary, and coronal to these said threads, there may be a machined/polished neck, which also appears to be submerged into bony tissue. This looks like a one stage tissue level implant that has been over-submerged. This may explain part of the problem. Of course, I would not expose threads above bone crest level. However, in this case, if my guess is correct about the implant design, the most coronal threads should have been placed just apical into bony tissue; and, because we may be dealing with an irregular bony crest morphology, any exposed threads could be grafted with the clinician's preferred technique, unless it would have been preferable to flatten the crest, or maybe use an implant with the ability to have soft tissue attachment to the exposed collar area such as the LaserLok from BioHorizons. About your insisting that one cannot augment vertically, I can only comment here that in certain situations vertical augmentation is predictable, but I will not comment on this possibility in this case simply because I do not know the case fully well to be able to assess with certainty. God Bless.

Dr Foster, the opposing dentition is a removable partial denture, not a complete denture.

Dr Foster, I did not say that implant size was the problem, my point was more about implant design and implant placement. And, with respect to the latter, we appear to have over-submerged implant-to-abutment and abutment-to-crown margins, and the ensuing possibly contributing negative sequelae, such as unfavorable crown-to-root ratio, unfavorable bone stress leading to bone loss to the first thread (and this pertains to the selected implant design), and possible retention of luting cement subgingivally at crown cementation. May God Bless.

Good point.....many denture patients sleep with teir dentures.

Don, occlusal overload may translate into excessive bone stress ... Bone modelling and remodelling ... Frost's Mechanostat Theory. Once bone is lost, the secondary result may be a peri-implant tissue pocket evolving vertically apically enough to harbour pathogenic micro-organisms that cannot be easily cleansed by the patient. In addition, it is perplexing to me that by this radiograph provided some clinicians on this thread can judge that the patient's hygiene is so terrible. I would say this is not necessarily so--based on the bone levels apical to the CEJ's of the neighboring teeth, there does not seem to be a huge periodontal issue. God Bless

Hi Peter, where is the case of vertical ridge growth. I have to say i struggle!!