Dear Atul,

There are three entrance exams NEET, AIIMS and JIPMER to provide admission in BDS colleges in India.

To check the top colleges for BDS you can refer below link

Guru Gobind Singh Indraprastha University, Delhi

Jamia Millia Islamia, New Delhi

Institute of Medical Sciences Banaras Hindu University, Varanasi 

King George's Medical University, Lucknow

Savitribai Phule Pune University, Pune

Sharda University, Greater Noida

To check the complete list you can refer below link

https://medicine.careers360.com/colleges/list-of-medicine-colleges-in-India?f%5B0%5D=sm_college_course_level%3AUG&f%5B1%5D=sm_college_degree%3AB.D.S

It is advisable that you should apply for medical colleges first as it has better scope in the future and entrance exams are same.

You can apply for BDS exams after completing your 12th class.

Good Luck!!