Hi, I sympathise greatly with you on the pure hell of mercury torment (years worth of it). I have had many years of torture from this poison and I know how it is, plus know the fears of the replacement materials and wondering if they were then making me ill too..
From my experience, there is no perfect material. The most you can do is get the least offensive to your system. Cerec is a good choice because it is not quite like hte old style porcelain. As for aluminium? not sure, there is some debate about that. Some types of cerec may contain it, some contain zirconium.
However, these are VERY stable. There are drawbacks to every material, but cerec is very hard, long lasting and again doesn't have the tendency to leak like plastics and amalgam.
I have just had half my composites replaced with cerec and yes, the dentist does indeed have to bond them in by using glue. I think he used heliobond and variolink II on me. Two materials to bond the cerec in. Then the block of cerec was put on top. Just as happened to you.
To avoid getting any plastic at all? You would need to get gold. However, the amount of plastic you have under the cerec would be minimal compared to how much you would have had you had the entire tooth done in composite. It also depends how well it was cured.
The other small composite you have may also be pretty mild. Some people have a mouth packed full of one material or another. Also, removing
Amalgams is far from the ending. The mercury still there, also sensitises a person's immunity to many things. Things you might not normally have a problem with, might suddenly become a problem when you are still mercury toxic.
It is vitally important to begin chelating the storage of mercury.
Amalgam removal is only the first step and simply turns off the tap. The best ways I know to heal from this condition is adherence to diet and a safe chelation protocol, diet to keep yeast levels controlled (which get out of control in any immune compromised situation, worsening an already vulnerable condition), and a safe chelation protocol to pull the mercury out of your tissues/organs and safely out of your system.
The best protocol I know for mercury chelation is by Andrew Hall Cutler. Many people are using his protocol on forums and seem to be tolerating his better than others they have tried.
I do understand your fear of reactions to the replacement materials and I went through that too and sometimes had material redone more than once, with no real changes and disappointment in the end. Figuring out that it was still the mercury that was causing the problems.
Also, after all
Amalgam is removed, it is not abnormal for people to get worse, sometimes much worse! Not only from exposure during removal, but it is a shock to the system, the body will try to withdraw from it and start to dump the storage. So you can feel "repoisoned". It is not a quick fix. But getting them out is the right move. Getting mercury out of your body is the next.