There is significant evidence that Crohn's disease is caused by Mercury poisoning resulting from the slow disintegration of dental fillings. The mercury release from fillings is absorbed primarily as highly toxic elemental mercury vapor. Anyone with Crohn's, Colitis, or IBS should review their dental history and seriously consider immediate removal of their amalgam fillings.
Most people born before 1975 have silver-murcury fillings, and by most I mean probably in the high 80% range. Personally I had 4 Silver-Mercury fillings. Only a tiny portion of the population suffers from Crohns disease. It could certainly be an agrivation for the disorder. Toxins in your system are bad for you in a miriad of ways but it cannot be said to be a cause based on the information linked.