The first set of false teeth similar to those in use today was made in france in the 1780's.
Ex: Colourful personalities abound, and people still recall one old miner whose set of false teeth was made of precious opal. Source
Note, false teeth were; the set was.
When in doubt, shorten it. Like this:
The first set was made....
...today it was made in france in the 1780's
...today was made in France in the 1780's/1780s
All the best.
Student or Learner