organized dentistry. You can go to iaomt.org or iadbm.org and see the science. In the holistic dental world, many do not believe RCT should be done. Some believe if done with ozone and a laser and with biocompatible filling materials, the body can tolerate it.
You already have disease, the dental infection. Root canal therapy eliminates the infection, it doesn't cause it. If left untreated, infection could affect you (temperature, fever, feeling lousy, or worse).
No, just a bacterial infection in your tooth.