We need two accents: η οδοντόβουρτσά σου. That's why it sounds rather weird.
Do you pronounce like: odandovourtsa?
Not exactly. More like Othondovurtsa (th- as in the) ^.^
there is a real hang up with dental hygiene in this part of the Greek course. all rather strange
I had "What is your toothbrush?" but it was marked wrong