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Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Aging and the shape of the mandible
Joel E Pessa1, D E Slice, Kevin R Hanz
1Houston, Texas; Vienna, Austria; Winston-Salem, N.C.; and Cleveland, Ohio From the Department of Plastic Surgery, University of Texas Southwestern Medical School; the Institute for Anthropology, University of Vienna; Wake Forest University; and Case Western Reserve School of Dentistry.
Plastic and Reconstructive Surgery
|January 8, 2008
Summary
The shape of the mandible changes significantly with age in both males and females due to differential growth, impacting facial aesthetics. Understanding these changes is crucial for cosmetic surgeons. Keywords: mandible shape, aging, facial aesthetics, cosmetic surgery.
Area of Science:
- Anthropology
- Plastic Surgery
- Biomedical Engineering
Background:
- Clinical observations suggest age-related changes in mandibular shape.
- Mandibular shape and size significantly influence the perception of youth.
- A pilot study was initiated to investigate these age-related mandibular alterations.
Purpose of the Study:
- To quantitatively analyze age-related changes in mandibular shape.
- To determine if these changes are statistically significant in both sexes.
- To inform cosmetic surgical approaches for facial rejuvenation.
Main Methods:
- Longitudinal data from the Bolton Brush Growth Study were analyzed.
- Serial frontal radiographs of 16 dentate individuals (8 male, 8 female) from youth to maturity were used.
- Geometric morphometric analysis was employed to assess mandibular shape changes.
Main Results:
- Statistically significant differences in mandibular shape were observed with age in both males (p=0.001) and females (p=0.02).
- The mandible exhibits continued growth, with differential growth rates in various areas contributing to shape alteration.
- These findings align with the principle of differential growth within the facial skeleton.
Conclusions:
- Mandibular shape undergoes significant age-related changes due to differential growth.
- Cosmetic surgeons must consider both bone and soft tissue contributions to lower facial appearance in older individuals.
- Creating an illusion of a smaller lower face through surgical procedures can enhance cosmetic outcomes, particularly in facelift procedures.
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