Will lip reposition relapse?

A common cause of Gummy Smile is an underdeveloped maxilla rather than a soft tissue problem. Yoy did not include photos to help in understanding problems.

Patients with very a narrow maxilla have a developmental problem that is orthopedic in nature. These patients have a narrow smile and space between back teeth and cheeks that appears dark.

Three dimensional Expansion with Epigenetic orthopedics or the DNA Appliance is my preferred approach to the narrow maxilla but MARE, SARPE and other surgical procedures are possible.

The soft tissue drapes over bone and teeth but the hard tissues actually determine what the facial tissues look like. Think about TV shows where they find bones and show facial pictures of what person probably looked like.
I typically utilize DNA Appliances to treat medical issues primarily but some patients come in specifically for cosmetic improvements.