Studies like this imply that maintaining facial bone density (“bone mineral density”) will reduce the appearance of aging on one’s face. From the publication:
OBJECTIVE: The authors demonstrate how the facial skeleton bone mineral density (BMD) changes with age in both men and women and compare these changes to those of the axial skeleton. They also explore the aesthetic implications of such changes in bone density.
CONCLUSIONS: Our results suggest that the BMD of the face changes with age, similar to the axial skeleton. This change in BMD may contribute to the appearance of the aging face and potentially affect facial rejuvenation procedures.
From wikipedia’s “bone density” page:
Bone density (or bone mineral density) is a medical term normally referring to the amount of mineral matter per square centimeter of bones. Bone density (or BMD) is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk.