Fractured implant: what caused this?

Good educational case to demonstrate lack of treatment planning. One implant is not enough to withstand functional loading in this long-span defect. Distal drifting underlines it. If custom abutments were not precisely made according to implant diameter, it would act as wedges after screwing.

Something else has changed here , what about the second premolar ? The bone loss down to the level of the bottom of the micro threads is an issue as well ...... Sure no-one used an elevator against it ..... Peter

The patient had attended his local dentist a day previously with the implant crown 'a little wobbly' no radiographs were taken and the patient stated that the dentist went 'hell for leather to try and remove the crown'. The dentist eventually gave up and instead of the crown just being loose it can now turn over 90 degrees in both directions. I think the attempted crown removal may have caused this?

These post are confusing, is huw providing additional information? Anyway I've had the pleasure of seeing this once, with a Nobel Trilobe connection it is called "implant flowering" where the implant splits along the weak spot in the Trilobe. It is possible that it was caused when the implant was placed if too much insertion torque applied in dense mandibular bone not noticed and it would spread over time. Other causes could be bruxism or no bone around the upper threads, none the less it needs to be removed. The bizarre thing is that the periapical is oriented to the tilted third molar and the premolar is missing now. What is the complete history? Extracting the premolar could have caused adjacent trauma to the implant. Another panorex would show the same orientation. A puzzle piece is missing here.

Sorry for confusion, I posted the original case. The initial implant was placed three years previously at a different practice. I saw the patient and placed 2 maxillary premolars implants and removed the decayed second premolar in view to restoration with implant after healing. The extraction was a simple forcep extraction, 3 months after he attended with this problem. Having removed a limited amount of implants using reverse torque techniques only I'm not sure I can get a adequate connection to allow this as the fixture is split. Any views in the electrosurgery technique to allow bone necrosis or just trephine out as normal?

I used the Neo Biotech remover it was fine and it covered the flowered part as the implant was removed.

As has been previously mentioned there are many possible causes (with the internal hex trilobe design being implicated in this type of occurrence). The implant has obviously been failing for a while as is shown by the bone loss around it, this is most probably occusal in origin. As was previously stated 2 implants should have been placed in this case as the cantilevers in both the vertical and horizontal planes are large. the angulation of the implant is also less than ideal.

The prior posters have made good points. The implant may be one made of CP titanium. Yes, occlusion may be an issue.

Hey guys, as usual I disagree, the upper teeth are waving in the breeze without much bone support. My hunch is that this implant was buried deep and placed with too much torque causing a fracture which flowered over time. I think the bone loss is due to periodontal disease. But anything can happen, I've seen implants fractured due to bruxism but usually there is more bone around the teeth with a widened PDL.

How many reasons do you need? 1. Uncontrolled periodontal disease 2. Missing teeth/disruption of occlusion 3. Evidence of heavy parafunction 4. Cantilevered restoration in posterior site 5. Underdiagnoses/inappropriate treatment planning 6. Operator inexperience 7. Patient non-compliance 8. Etc., etc., etc. Amazing it worked initially. Don't blame the implant.

1, Trilobe are among the most fractured implants due to its design and yes most of them are grade 2 or grade 4 cp Ti. 2. The bone has gone down, yes, as it would in a natural tooth also, fractured implants don´t just split, they usually have a period of mechanical expansion of the fracture and that gives you bone loss as a clinical and radiological indication/result so I think CRS is right, this implant might have been placed at bone level.... maybe 3. implant has not tilted and or drifted, is in the exact same position what happens is that the x ray has been taken with a different angle and as the crowns has changed position angling itself to the mesial, and the premolar is gone, it only seems that way. 4.- I use the NeoBiotech removal kit, also, I would graft that site with easygraft and since "2" implants have been placed in the premolars i would place a replacement in the same act , taking care that it is parallel to the other ones and get a a nice 4 unit bridge or a 3 unit fixed partial, depending on your personal orientation and loose the failing third molar. During he healing period make the effort to prepare a correct occlusion. Cheers

The type of implant is really not a factor, CP or alloyed, whatever; I've seen just about everything fracture, distort or flower and the commonality was the laundry list Kucey posted. The clock was ticking on this one so none should be surprised by the result.

Occlusal trauma should most probably be the reason , even more so if pt is a bruxer. Now the implant lies in an anterior posterior direction, and I think it would not have been same if it was inclined slightly posteriorly. Any thoughts about group or canine protection ?? I cannot really see that on the radiography.

I know the exact cause of this fracture. I had a patient come to me from another dentist with the coronal socket fractured on the implant just like this one. Investigation revealed that the implant crown had become quite loose and he was 'too busy' to go in and have it tightened for several months. Under those circumstances, the crown lifts up in the socket at an angle and then the occlusion comes down on it, then the abutment in the crown now torques the side of the implant head socket like a lever-bar, exerting tremendous leverage force on the side of the socket until it fractures.

I would also point out that the second x-ray is deceptive. The implant has not moved or migrated. The implant socket was already broken when someone tried to tighten it back down, then took an x-ray to see what was wrong.

There are a lot of good suggestion made above. In my opinion, this case was poorly treatment planned. The third molar should have been removed prior to starting, and two 6mm x 8 mm implants installed. The problem with internally hexed implants, is that when too much force is applied when installing them, the thin wall in the hex area is being distorted and weakened, and you do not know the consequences of this until the crown is made months later. I have a lot of experience with ADIN Implants, and the 6mm in diameter have very strong walls, that will not get stretched or damaged during installation. Gerald Rudick dds Montreal Canada

That what happens when laws of physics and physiology are ignored and violated. It's called metal fatigue. Was the screw loosening responsible for that fracture? It doesn't matter . Wide implant (7+mm) should have been used. It wouldn't had been neither any screw loosening, not fracture. Were there Not enough bone to place such implant size? Make it then there.

Have a look at the very bad fit of the abutment on the implant platform. Please ask the technician what he did use and ask for original on original. Respect the maximum torque for the abutment screws. R.G.A. Peters

I'm confused by all the comments about occlusal trauma and bruxism. Doesn't everyone take these completely out of occlusion using shim stock for a bruxer? There shouldn't be a problem with occlusion or occlusal trauma unless it was a motor vehicle accident and the guy hit his face on the steering wheel.