We just saw an interesting page on dental implant failure from the website of Dr. Arthur Chal of Arizona. Dr. Chal apparently sees a lot of patients who have dental implant failure, and he discusses the various manifestations of this.
This, for example, is a photograph of a substandard fixture removed from a patient. Since it didn’t fit properly, it had become loose and allowed infected material to get in around it and had become loose.
It’s important, if you have implants placed, that you use a qualified implant dentist like Dr. Whitmore with adequate training and who uses quality fixtures and techniques.