Yeah, definitely look at each school you're applying too. Most list it on their websites under application components or something like that.
For some, you're probably going to need either another non-science professor letter or one from a dentist, but definitely check into it.
I maxed out on my AADSAS 4 with 2 science, 1 dentist, and 1 non-science.. but I had two schools that required a 3rd science so I just had that 3rd science letter sent directly to the schools (not through AADSAS)
As you can tell, it was kind of a pain, but most schools are different in what they want so definitely check! 🙂