Failing Bicon Implants. How would you treat?

Hi CRS, I am interested in your comment that 10 years is considered pretty good in terms of lifespan for the implants. In general, what lifespan do you tell your patients who choose to have implants (given all things considered and in an ideal situation)?

In medicine, there are no guarentees, for some reason as dentists we feel that we have to guarentee and warrantee everything. In orthopedics the average lifespan of a hip prosthesis is ten years, then the surgeon goes a "revision" and puts in a new one if needed. Lots of factors here. Based on my experience I tell patients, implants can last twenty years based on the research but success rates are quoted after the first year when the implants are fully integrated and restored. Another benchmark is 8 years out when we start seeing peri implantitis, the bacteria are still in the mouth! What I do think is important is setting the implant up for success, good bone support with grafting and soft tissue, good occlusion and oral hygiene maintenance. Here is a personal note root canals usually last 10-15 years, crowns around twenty. A deciduous tooth left in situ as a spacer lasts up to age 25-30. If a patient lives long enough the wisdom teeth will need to be removed due to perio or decay.These are general guidelines based on my experience as an oral surgeon. Telling a patient an implant will last a lifetime is a sales pitch! Of course there are always outliers and the patient's natural tooth if it can be reasonably saved is always best, coming from someone with a livelihood pulling teeth and placing implants. I hope these humble guidelines will help you in your treatment planning discussions with your patients. I think that the high bar set in dental school is very important when pursuing excellence in learning technique, and I personally strive for it on every case. But giving patients more realistic guidelines is more practical . Good luck and thanks for the question!

Thank you David for your feedback. The answer is no, I do not work for Bicon... It happens that my academic background allowed me to research a bit and play a bit more with various implant systems (since 2002...). One of Bicon's innovations is relied upon the design of their abutments. The hemispherical base (I do not know how else should I call it, sorry!!!!) of the abutment provides excellent support to the underlying soft tissues and bone contributing to a remarkable emerrgence profile. The hemispherical base should not be trimmed by the lab and the margins of the crown have to be far away from the implant well. According to my opinion, this is why Bicon implants do not suffer from bone loss around their threads (bone modification?). The few times that I saw Bicon implants fail, it is always the design of the abutment... And this is consistent with the X-rays of this case! I totally agree with CRS that ten years is a LONG time... Thank you again for your feedback David.

The hemispherical base as it is actually called, is the key to solid prosthetic work on Bicon implants. Besides providing an emergence profile and supportive base for the actual crown, it also helps to stimulate the bone during load (Wolff's law) thus, in many cases, resulting in bone gain. It needs to be a hemisphere and it needs to be as close to the bone as possible. The ideal width of the hemispherical base for a molar for instance should be 6,5 mm or more. I agree that in this case host factors are most likely at play but I must say that I see less problems with Bicon implants and peri-implantitis compared to other systems, but of course, that is my personal experience. Bicon truly is a great system to work with, but every party involved and especially the dental lab technician needs to know exactly what they are doing. Just follow the protocol!

"I have also used the shoulder and also even a fin as the crown margin. You can do this because there is no screw to allow the passage of bacteria to travel down the threads. In this way it Bicons seem to be more resistant to failure due to infection". ************************** This, the above quote, seem to be a bit irrational. Bicon's restorations; Implant "well" and the corresponding "post" of the abutment are being created with a 1. precisely machined 2.5 degree MORSE TAPER, (I am not sure if it is 1.5) 2. which (the tapers) upon "proper assemble/ing" results in a mechanical cold weld at their interface that is impermeable to micro organism. 3. Such a seal maintains and prevents bacterial invasion, migration along and or localization of microbes, because of ABSENCE of any form of mechanical micro-space between the surface interfaces of the fixtures. Now, Using the "shoulder and also the fin" as a "crown margin" ..... impossible & impractical!!!!!! Here is why, A. Once the Bicon implant is integrated, there is no clinically practical and mechanically possible means for recording and duplicating the bevel and or the fin part of the fixture. B. Even, if in case, one other implant fixture be used as an analog over the lab bench for the prosthesis (crown) fabrication, C. The crown/bevel interface in the mouth would be a perfect "iatrogenic" microbial pouch and or a "bacterial reservoir". D. Bicon's bevel is designed for attachment of soft tissue and or migration of crestal bone on to it, when a "mechanical & bio-physiologically favorable" configuration is being created by the clinicians. I realise this post is nearing three years old, but I am tempted to respond as I did. Open for comments, questions and constructive criticism. Ashwath M Gowda. DDS.

I would like to see some of these failing Bicon cases Laz S!!! I dare make the null hypothesis that all of them would have had issues with the restoration on top of them (lack of ovate base of the abutment, once again...!). Astra along with Ankylos are systems that rely upon the conical connection between the implant and abutment (which was first introduced by Driskell in '78 as correctly posted by PeterFairbairn)! These three systems (Bicon, Astra, Ankylos) can provide a very predictable outcome! I agree with your opinion about the Astra system! I like it very much! But it is so similar with... BICON!!!! Thank you all for your input guys!!!!

Thank you Dr Will J!!

Thanks for the feedback, you are also wise!