Implant failing in extremely dense bone: prospects to replace?
3 months ago I placed implants in a 50-year old Asian man in good physical health in the 19, 20, and 21 areas. On the pre-op CBCT, the Mn bone in the 20 and 21 areas has the appearance of cortical bone through the width of the Mn down to about 10 mm. Almost an imperceptible difference in appearance from the cortical plate to midwidth of the Mn. I had originally planned to do a 10 mm implant, but after a period of time gave up went with a 6 mm implant. Due to the density of the bone used heavy irrigation, and bur set had only been used twice. PA taken at time of impression for the prosthetics showed a failing #19 with 3 mm bone loss and #20 having lost 3 mm on the distal, but M was perfect. #19 will need to be backed out. When preparing the osteotomy for 19 there was basically no bleeding. Looked like osteotomy was in chalk. What are my prospects for retreatment in this area? I am somewhat doubtful that #2 round bur perforations within the osteotomy will be of any assistance. Thank you
11 Comments on Implant failing in extremely dense bone: prospects to replace?
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implant guy
3/22/2018
wow....what kind of implants?
Richard Hughes
3/22/2018
No blood..........no osseointegration..........period!
Got to “Let it Bleedâ€
Timothy C Carter
3/22/2018
I was taught during my perio residency that there 3 factors which determine surgical success or failure and they are 1. Blood Supply, 2. Blood Supply, 3. Blood Supply. In the absence of any of the three the procedure is destined to fail. It looks like this is just not a good case for implant therapy. It doesn't matter the type/kind of implant used this is just not gonna be a winner.
mark simpson
3/22/2018
you must drill in short spurts then give it a minute then drill again it is really easy to over heat hard bone . Its happened to everyone if they have placed enough implants
Dok
3/22/2018
The usual suspects:
Avascular necrosis ( not enough cancellous bone/blood supply for healing ), pressure necrosis ( too high a torque force used in the dense bone ) or temperature necrosis ( overheated bone during the difficult osteotomy ) are all possible etiologic factors to be avoided next time around. Review/re-live your surgical approach and see if any of the above scenarios may have somehow been involved and if so, tweek your approach accordingly. Aggressively threaded implants may also need to be avoided. Also, does this patient have an underlying systemic condition or drug related issue ? I always say to myself, "if I am not sure, I should refer".
Dorian Hatchuel
3/22/2018
In these cases of dense bone perform a site preparation. Drill out the "inner bone" leaving the cortical "shell". Use a Zachariah bur. Graft the site with Allograft, PRF and cover with a membrane. Return after 3 months and place your implants (computer guided of course). The bone will be type III.
K,kavvouras
3/22/2018
I believe that in some cases where the bone is very dense, and the blood supply poor,,,is better to make the drilling and reentry after 3 months exactly in the same area so that the new bone will be softer and the blood supply better
Rick
3/22/2018
Thank you one and all for your generous responses. I am leaning towards lack of vascularity as the probable cause. Am pretty experienced--closing in on 2000 implants. So, used heavy irrigation and after placement ratcheted it back about half a turn to try to prevent pressure necrosis. I think I will back out implant, graft area, wait 3 months and do a pilot drill osteotomy to check for changes in vascularity. Once again, thank you and I always find great value in everyone's responses to all questions posed.
Robert Wolanski
3/22/2018
Some great comments here. One must take the poor blood supply of cortical bone very seriously in treatment planning the case. CT's are essential here as you can gauge the level of cortical and cancellous bone on cross section. If you do not respect the principals you can have implants fail years after the placement which usually means you did not overheat the bone (those fail quickly). It looks like this; the patient has no problems, symptoms of crestal bone loss for years. All of a sudden the patient presents with tissue sloughing and exposing necrotic bone and your heart sinks. You remove the necrotic bone to a level where the bone bleeds because you know this will allow the fibroblasts to migrate over and cover the bone. It does not work the first time and tissue continues to slough. Threads are now showing. You remove bone again and find the bleeding vascular vital bone and again pray it works. It does and you see the tissue covering the bone. You do some implantoplasty and the case stabilizes. Great , but the implants are compromised. Today with CT scans and good advice like Hatchuel and kavvouras have given.
Dennis Flanagan DDS MSc
3/23/2018
There will be heat generated during seating of the implant. So much so that some brands may need irrigation to disperse the heat so it does not seriously damage osteocytes. This may cause bone loss.
J Oral Implantol 2014-Apr 40(2):174-181 Heat generated during implant seating
Neil Zachs
3/23/2018
I agree with Tim Carter's response...It is ALL about blood supply. If it is not there, implants will not work. Obviously drilling slowly with copious irrigation is key and tapping a site may be necessary at times, but none of that matters without a bleed to the site. Period. It sounds to me like this guy is just a poor implant candidate. I wouldn't try again
Neil Zachs, Periodontist, Scottsdale AZ
