Is it possible to use fillers to address my facial asymmetry and narrow appearance?

Fillers (along with fat injections) can help shape the face. Increasing width, length, creating definition, restoring volume, increasing prominence in some areas and such. They can also help improve asymmetries in the face. If you also intend to add more definition to your face, you may also benefit from a buccal fat removal surgery. It's best you consult a board certified facial aesthetics specialist and discuss your desires and options.