should be ok. degusa is what he wants to use right?
porcelain fillings are safe in my mind. but very expensive.
"composite" fillings are ALL cytotoxic, from the studies i found on the net. also very hard to find out what is in them. all the composites are at least 60% metal. 60-80% metal is the norm.
barium, tin, and aluminum is what is in the best of them. the plastics are no bound tightly like in porcelain. porcelain has very high material integrity.