It may take more than a facelift to keep up that youthful appearance.

According to a study by physicians at the University of Rochester Medical Center, changes in facial bones—as detected by a series of CT scans—occur over time and could affect how people appear as they age.

The study, presented March 23 at the annual meeting of the American Association of Plastic Surgeons and published in the Journal of Plastic and Reconstructive Surgery, suggests that to provide patients with the desired youthful look, some kind of facial reconstruction may actually be necessary before skin straightening procedures are attempted.

Howard Langstein, MD, a professor and chief of plastic and reconstructive surgery at the University of Rochester Medical Center in New York, and colleagues, reviewed 120 facial CT scans that had been taken for other medical reasons and measured the facial changes that occurred to the bones over time. The researchers divided the scans by gender and age--20 men and 20 women in each of three age groups: young (ages 20-36), middle (41 to 64), and old (65 and older)—and used a computer program to measure the length, width and angle of the jaw bone for each scan, comparing the results for each group.

They found that the angle of the jaw increases with age, resulting in a loss of definition of the lower part of the face. Specifically, they found that jaw length decreases within the middle age groups compared to the younger group and that the decline in jaw height in the older group was signicant.

“The jaw is the foundation of the lower face, and changes to it affect facial aesthetics,” said Langstein. “These measurements indicate a significant decline in the jaw’s volume as a person ages, and therefore less support of soft tissue of the lower face and neck.”

Langstein said the loss of bony volume could contribute to sagging facial skin and that the decline in jaw volume could lead to a softer, oval appearance around the chin.

“Physicians have long been taught that facial aging is caused by soft tissue descent and loss of elasticity,” Langstein said. “Though we have always known that bones change over time, until now, the extent to which it causes an aged appearance was not appreciated.”

Co-author Robert B. Shaw, Jr., MD, also from the University of Rochester Medical Center, said that future facial cosmetic procedures may have to include “methods to suspend soft tissue – such as chin and cheek implants – to rebuild the structure that time has worn away, in addition to lifting and reducing excess skin.”