In my experience; I’ve noticed various mini dentures. Probably, when patients start to complain of sore spots, a dentist just grinds dentures away.
In dental school, we are taught there are 3 components in successful removable dentures; retention, support, and stability. For complete denture, you get retention from adhesion and cohesion so the contact area is larger you have a more retentive denture. That’s why most people are happy with the upper denture and the lower denture is hard to be retentive. (Due to the tongue; which takes up space and moves denture around.) The key to success is to be experienced in this field of expertise.