Ancient Greek doctors did not necessarily believe this and there is little evidence they did as a whole. The rumor of their doctors thinking this comes from a statement from Aristotle. He is the only one to have made such an assertion and the statement is grouped in with other gross misconceptions regarding the females of multiple species. In the same collection of writings he discusses bee hives headed by a king rather than a queen, and other animal falsities I can not recall off hand. This was all in a discussion where he was demonstrating how female's of species were lesser. He mentions smaller brain size, less physical defensive features, etc,. None of his statements were base on empirical evidence, but rather statements designed to defend his point regarding the inferiority of the female 'species'. What is not known, is how intentional this was in terms of if he truly thought these things or simply used them to try and hammer home his own point. I will leave that speculation for elsewhere. Ultimately, there is little evidence I am aware of that demonstrates the 'tooth fallacy' outside of his work or others quoting his work.

EDIT: Some grammar and typos.