How can I get rid of smile lines on one side of my face? (Photo)

Dear shika99,
Thank you for your question. It is difficult to make an accurate assessment and recommendations based on photographs alone. I recommend you seek an in-person consultation with a facial plastic surgeon or plastic surgeon who can perform a thorough examination and recommend the best treatment options to address your goals. It is always natural to have nasolabial folds and overtreating them with filler can lead to an unnatural appearance. If you are seeking more symmetry in your face as the one side no longer has a fold due to the accident, filler is a nice treatment option to help minimize the nasolabial fold on the other side and make your face more symmetrical. 

Hi the pic is not very clear but based on what I see the nasolabial fold on the left side is deeper so my first choice would be to use a filler such as radiesse which is calcium based and over a 1-2 year period will stimulate collagen.It gives a permanent effect without a permanent product