Hi, there's no dental check up =)
They are not looking for scientist or scholars, but pilots. Doesn't mean that if you have 3 As and another person got 6 As, he will get in and you won't.
Most importantly is, when SIA HR looks at your results, they must have the confidence that you have the calibre to get through the intense studying required for ATPL.
Based on what other ppl had said before, the minumum requirement is bla bla bla, you can check the previous posts. Anything more is just a bonus but not critical.
Good luck to you, and to me!