Can you tell me if i could modify my teeth as shark's?

Probably not: Personally, you would have to mutilate your teeth to the point of cutting them deep into the dentin, a process that would be quite painful without a local anesthetic. They would then be cavity prone and sensitive to hot, cold, and sweets, possibly needing root canal tx. Restoring them back to human form can cost $ 3500+ per tooth.. Unlike a shark, you do not grown new sets of teeth.