Okay I believe an apicoectomy is when they fill the roots with mercury/amalgam. It is a kind of root canal or a deep filling.
I know someone who got VERY VERY VERY ill to the point of death and right on par with me when I was first sick, from this procedure. Gutta percha is a gummy like substance and the usual material used on a normal root canal in which they suck up the dead tooth pulp and stuff and fill it with the rubbery substance. The argument is that it will fill the tooth fine However, the tooth has tiny little cavities.
This is my holistic biological dentist talking a little on the subject matter.