Good day
It is important to note, that the older you get, your muscles and skin lose "elasticity" . It is natural to show less teeth, the older you get.
On the photo it is clear though, that you are not giving the biggest smile possible. These days, with proper planning and crowns or composite build ups, you can increase the amount of teeth shown. Proper planning is very important, so I would recommend seeing a dentist that specializes in prosthodontic make overs.