If it's a superficial stains,
Can do scaling& polishing, costs Rs. 1000.
If the stains are deeper & penetrated then
BLEACHING, Rs 5000 till 10,000.
U can also veneer it, if there is change on shape or Alignment, which also blocks all dark stains. Rs. 8000
Next Steps
scaling
Health Tips
use branded tooth paste which doesn't make your tooth surface rough