entry requirement: international baccalaureate and a-level

Hello guys
Basically my question is what is international baccalaureate/ iB diploma program? I want apply to dentistry for Queen Mary University and one of the requirements is iB diploma program. I have no clue what it is and for reference i am British living in East London and have done a-levels (A*,A,A). Do I have to do the iB diploma program? Is it a requirement that I must fulfill?

No, you don't need to do the IB.

The IBDP is an alternate level 3 qualification, (equivalent to A-Levels). It's taken around the world and moreso in places where students might be applying internationally.