You're neglecting—or abusing—your teeth.
Teeth add structure and vertical height to the face. When they get worn down through grinding, nail biting or aggressive chewing, or worse, when a diseased tooth needs to be pulled, the facial skin can become looser, explains Phil Haeck, MD, a plastic surgeon based in Seattle and the past president of the American Society of Plastic Surgeons. Combined with the skin's natural loss of elasticity over time, this can lead to wrinkles and sagging around the mouth. Dentures help fill in the gaps left by missing teeth, but dental implants do a better job at restoring the height of the jaw, Haeck says. You know what to do: Brush twice a day, have your teeth professionally cleaned at least once a year and remember to floss. If grinding is a problem, talk to your dentist about a bite guard.