I think 1 is more than enough despite the size of the polycule and keeps the counter looking tidy. What do you think?
Update: getting an electric tooth brush with our first fruits and getting a separate brush attachment for each of us that we can make a piece of pottery to hold super easy! Thanks for the input those that were helpful!
The logic would be that one toothbrush is capable of serving many more people than the polycule contains.