The internet is usually rife with medical problems and unknown ailments. There are a lot of articles dealing with medical issues in an alarmist way, and it is often hard to differentiate between medical truths and scare tactics for some ill advised marketing scheme. Usually it is enough to just lo at what sort of scientific evidence supports the claims being made, and who gives the funding for the website. Certain issues, however, are just not clear. One of these issues is the existence of implant rejection.
Many dentists state that there is no such thing as dental implant rejection, it is simply impossible, as the body does not reject titanium. Seeing as the tissue surrounding and binding the implant is your own, there is not even the sort of rejection that occurs with heart and other organ transplants, as the dental implant is not a biological compound. This is logical, and makes perfect sense. However, it is not entirely true. This article, for example mentions the symptoms of what they call implant rejection. They mention redness and swelling of the gum around the implant, and bone loss which results in the implant beginning to move. Thus, the body tries to remove the dental implant. Wikipedia also confirms this as something known to happen. So who to believe?
As frequently is the case with scientific arguments, the answer is confusing: they are both right. The issue is rooted in the fact that we do not understand why the body does not recognize titanium as a foreign object. In 5% of the cases where implants fail the reason is completely unknown. Unlike organ transplant rejection, implant rejection is more similar to the body’s reaction to a foreign object (like a splinter or shrapnel) although the symptoms appear to be different. So the issue is largely an issue with nomenclature. But this does not mean that the threats are not real, as dental implants can fail where initially they seemed to be good, and none of the known factors - i.e. bone density, mucosa, and periodontal health - seem to suggest the possibility of a problem. The only solace that can be given in these times is that implant rejection, for lack of a better term, happens early on, and your implant will fail before your healing screw is placed in.