Hello dear student,

Although you have obtained 490 marks in NEET and even you have obc category still there are very less chances for you to get admission in any government dental college. As cut offs are really high as last marks at which seat is alloted is around 510. Still you can try for the college's. I am sharing a link with you. Kindly check it and fill the college carefully 

https://www.google.com/amp/s/medicine.careers360.com/articles/neet-cut-off-for-government-colleges/amp

I hope this was helpful to you

Best wishes