How long before my tooth falls out? (Photo)

It is common for front teeth to begin to shift and crowd beginning around age 20 years.  You may want to consider a bonded retainer wire to prevent teeth from shifting.  Also, the gum recession that I see in this photo is mild and you would likely get the same advice in my office.  However, you can certainly take a more proactive approach by removing the tight frenum attachment (that piece of tissue holding your lower lip to your gums).  In my office this is a minor procedure done with a laser.  You could even have a small gum graft to bolster the amount of gum tissue around the tooth in question.  Your dentist is correct that oral hygiene is critical to keeping a healthy mouth.  A healthy diet and healthy habits are just as important.