For BDS admission under the OBC category through NEET, the closing rank depends on the year and the type of college. But usually, if you are from the OBC category and want to get a seat in a government dental college through All India Quota, your NEET score should be at least 520 to 540 marks. This means your rank should be under 3,00,000 to have a better chance.

Last year, many OBC students got BDS seats in government colleges with ranks around 3,50,000 or a little more. But for top dental colleges like in Mumbai, Delhi, or Bangalore, the cutoff can go higher, around 540 to 560 marks.

In state quota counselling, the cutoff may be a little lower depending on your state. So even if your rank is a little above 3 lakh, you may still get a seat through your state counselling, especially in private or semi-government colleges.

You can check more details here:
https://medicine.careers360.com/articles/bds-cutoff-for-neet