Hi Deepak,

As per your query about the marks required for BDS, I would like to inform you that it will vary every year based on the difficulty level of ques paper and number of students scoring that mark
It also depends on college you targeting like govt or private... Through STATE QUOTA 85%  Or ALL INDIA QUOTA 15 %.....
BUT going by previous years trend for government college in obc category 450-550 will be a safer score.. If you target private it will around 400-500 .

Hopefully it helps!!