If you still hav dental amalam aka silver fillings you should NOT practice oil pulling until you hav it/them replaced
By pulling (friction) the oil across the fillings you're essentially just loading up your system w/lots of heavy metals leached from the fillings https://www.youtube.com/watch?v=OwifA_sCDU4
I would address this issue by not only having my silver fillings replaced but by ingesting zeolite which binds heavy metals and passes the metals out of your system. I like Zeoforce by Health Force
Some of the reasons Ive read for people practicing oil pulling could be helped by removing heavy metals, ditching the microwave, adding minerals and healthy fats