The nasolabial fold: a photogrammetric analysis

Area of Science:

• Facial anatomy
• Aging research
• Biomechanical analysis

Background:

• The nasolabial fold is a prominent facial feature affected by aging.
• Understanding age-related changes in facial soft tissues is crucial for aesthetic and reconstructive science.

Purpose of the Study:

• To analyze the changes in the nasolabial fold and adjacent soft tissues associated with aging.
• To investigate the biomechanical factors contributing to the deepening of the nasolabial fold over time.

Main Methods:

• Longitudinal analysis of chronologic photographs from subjects aged 20 to their present age.
• Photographic analysis of facial portraits (repose and smiling) in young and old adults using a standardized mechanical frame.
• Measurement of facial landmark displacements and fold depth in anteroposterior and coronal planes, with normalization using facial dimensions.

Main Results:

• Aging leads to anterior, lateral, and inferior displacement of the cheek mass.
• This displacement results in a deepening of the nasolabial fold, while upper lip-fold relationships remain constant.
• The lateral commissure moves laterally with age, and the apparent nasolabial fold angle decreases due to reduced horizontal fold length.

Conclusions:

• The deepening of the nasolabial fold with aging is primarily attributed to changes in the cheek mass and its underlying support structures.
• Age-related soft-tissue displacement significantly impacts facial aesthetics, particularly the prominence of the nasolabial fold.
• Quantitative analysis of facial changes provides insights into the biomechanics of facial aging.