The labial aging process: a surface analysis-based three-dimensional evaluation

Differences in the 3-dimensional aging changes of the lips among female adults with skeletal Class I, II, and III malocclusion

INTRODUCTION

The objective of this study was to evaluate and compare the 3-dimensional (3D) aging changes of the lips among adult skeletal Class I, II, and III malocclusion.

METHODS

Female adult orthodontic patients aged 20-50 years with pretreatment cone-beam computed tomography scans were retrospectively classified according to age (20s [20-29 years], 30s [30-39 years], and 40s [40-49 years]) and then subclassified by malocclusion into skeletal Class I, II, and III relationship (9 groups; n = 30 per group). Positional differences in midsagittal and parasagittal soft-tissue landmarks and 3D morphologic aging changes of the lips were evaluated using cone-beam computed tomography scans.

RESULTS

Labiale superius and cheilion for patients in their 40s indicated a significant downward and backward position compared with those in their 20s, regardless of skeletal classifications (P <0.05). Accordingly, the upper lip height decreased, and the mouth width increased significantly (P <0.05). For Class III malocclusion, the upper lip vermilion angle was greater for patients in their 40s than those in their 20s (P <0.05), whereas the lower lip vermilion angle was only lower for patients with Class II malocclusion (P <0.05).

CONCLUSIONS

Middle-aged adult females (40-49 years) had a lower upper lip height and greater mouth width than those in their 20s, regardless of skeletal malocclusion. However, prominent morphologic aging changes of the lips were noted on the upper lip for skeletal Class III malocclusion and the lower lip for skeletal Class II malocclusion, implying that the underlying skeletal features (or malocclusion) may influence 3D aging changes of the lips.

Three-dimensional analysis of modeled facial aging and sexual dimorphism from juvenile to elderly age

A detailed understanding of craniofacial ontogenetic development is important in a variety of scientific disciplines dealing with facial reconstruction, forensic identification, ageing prediction, and monitoring of pathological growth, including the effect of therapy. The main goals of this study were (1) the construction of the facial aging model using local polynomial regression fitting separately for both sexes, (2) evaluation of the aging effect not only on facial form as a whole but also on dimensions important for clinical practice, and (3) monitoring of the development of shape facial sexual dimorphism. Our study was based on the form and shape analysis of three-dimensional facial surface models of 456 individuals aged 14-83 years. The facial models were obtained using a structured light-based optical scanner and divided (for some analyses) into four age categories (juveniles, young adults, middle adults, and elderly adults). The methodology was based on geometric and classic morphometrics including multivariate statistics. Aging in both sexes shared common traits such as more pronounced facial roundness reducing facial convexity, sagging soft tissue, smaller visible areas of the eyes, greater nose, and thinner lips. In contrast to female faces, male faces increase in size until almost 30 years of age. After the age of 70, male facial size not only stagnates, like in females, but actually decreases slightly. Sexual dimorphic traits tended to diminish in the frontal and orbitonasal areas and increase in the gonial area.

Stereophotogrammetry to reveal age-related changes of labial morphology among Chinese women aging from 20 to 60

Background

The lip is of important aesthetic value and highly subjected to aging. Collecting anthropometric baseline data and understanding age‐related changes of labial morphology can help with diagnosis of deformity, assessment of aging, and planning of cosmetic procedures. Many studies have focused on Caucasians, while there is a lack of anthropometric data on Chinese women.

Methods

A total of 169 women were enrolled in this cross‐sectional study and divided into four consecutive age groups. Linear distances, angles, and surface area data were obtained via stereophotogrammetry. Intergroup comparisons between different age groups were performed to find age‐related differences.

Results

Lip width significantly increased with age while philtrum width seemed to show no obvious change. Cutaneous upper and lower lip height increased, lengthening the lip in the vertical dimension. Decrease of upper vermilion height and changes in angles indicated that aging process shortened the upper vermilion and flattened the vermilion border. Surface area also showed age‐related changes. Intergroup comparison showed no statistical significance in most variables between 20s and 30s or 30s and 40s, while age‐related changes in some variables were significant between 40s and 50s.

Conclusion

This study provided anthropometric data of labial morphology across a wide age range. Aging process affected a variety of labial anthropometric variables. Age‐related changes accelerated after 40 among Chinese women.

Lip Morphology and Aesthetics: Study Review and Prospects in Plastic Surgery

The lip profile plays an important role in the perception of facial aesthetics; lip morphology and aesthetics research is receiving increasing attention. The advancement of research tools such as three-dimensional imaging technology has led to the clarification of lip morphologic and aesthetic characteristics. After studies of lip characteristics according to gender, ethnicity and age provided basic data, studies on lip aesthetics have been conducted by scholars worldwide. These studies could provide a basic theory to support diagnosis and treatment options, as well as the basis for evaluative criteria for precise treatment and technical improvements. According to the conclusions of the above studies, new ideas for cosmetic surgery design, including lip, perioral and labial-facial relationships, have been discovered.Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Variability of facial movements in relation to sexual dimorphism and age: three-dimensional geometric morphometric study

The aim of this study was to introduce suitable imaging technique and analytical methods for a detailed description of the facial movements in relation to sexual dimorphism and age in adult individuals. Removing of size factor from the analysis, we hypothesised that there will be no significant intersexual difference in facial mobility. We assume facial movements to be more pronounced in the older age category due to increasing the facial surface. We have compared five facial movements - raising eyebrows, closing eyes, pursing of the lips, inflating of the cheeks and smile - in relation to neutral expression of the human face. The material sample comprised three-dimensional facial surface models of healthy adult individuals of the Czech nationality (63 females, 58 males). Methods of geometric morphometry and multivariate statistics were used. Local tissue motion due to facial movements was expressed using colour-coded maps. The movement showing significant intersexual difference was inflating of the cheeks. Ageing in both sexes has significantly influenced the facial mobility on average after 50 years of age. Changes related to senescence have occurred in eye closing, smile and inflating of the cheeks. An enlarged facial surface has been noted in the group of individuals belonging to the older age category, what is probably the result of increased manifestation of skin folds and wrinkles. This is related to the loss of skin elasticity and overall weakening of the underlying muscles, especially in the infraorbital and cheeks area.

Age-Related Changes of the Orolabial Region in Caucasian Women: An Anthropometric Analysis

PURPOSE

Anthropometric data can provide valuable support for the attending physician in planning surgical and nonsurgical esthetic procedures with regard to a patient's age. The purpose of the present study was to identify age-related orolabial changes in younger and older Caucasian women.

MATERIALS AND METHODS

In the present cross-sectional study, anthropometric landmarks were identified using indirect anthropometry (2-dimensional photometry) in younger (≤35 yr) and older (≥50 yr) Caucasian women to analyze age-related parameters and proportions of the orolabial region, especially of the lower and upper lip vermilion areas. The Mann-Whitney U test was applied to compare the results between the younger and older populations.

RESULTS

The study population consisted of 45 women. The cohort was divided into a younger population (24 participants; mean age, 27.4 yr) and an older population (21 participants; mean age, 58 yr) to evaluate age-related differences. Increases of upper lip height, cutaneous height of the upper lip, and cutaneous height of the lower lip were observed in older women. In contrast, the vermilion height of the lower lip decreased significantly with increasing age.

CONCLUSION

These results show changes of the orolabial region occur in Caucasian women with increasing age. The statistically relevant decrease of the vermilion height of the lower lip should be given particular attention for (age-appropriate) diagnostic, esthetic, and prosthetic treatment planning.

The influence of age on lip-line cant in adults: a cross-sectional study

OBJECTIVE

The aims of this study were to assess the direction and degree of lip-line cant in Korean adult orthodontic patients and to identify the effects of sex and age on changes in the cant severity.

METHODS

In this cross-sectional retrospective study, lip-line cant was measured in the frontal photographs of 585 Korean patients (92 men and 493 women) aged 18-48 years. The outcome variables (direction and degree of lip-line cant) were assessed in terms of predictor variables (sex, age, sagittal skeletal relationship, and menton deviation angle).

RESULTS

The direction of lip-line cant did not differ according to sex, age, or skeletal classification. Patients had 1.6° of lip-line cant on average before orthodontic treatment. Middle-aged adults displayed a significant trend toward a lower degree of lip-line cant compared to younger adults (p < 0.01). Multiple linear regression analysis showed that the degree of lip-line cant was weakly negatively correlated with age (p < 0.001).

CONCLUSIONS

While the direction of lip-line cant did not differ according to the parameters explored here, the degree of cant was correlated with age in adults, independent of menton deviation. Specifically, middle-aged adults tended to display significantly lower degrees of lip-line cant than did younger adults.

Sexual dimorphism of facial appearance in ageing human adults: A cross-sectional study

In the forensic sciences, knowledge of facial ageing is very important in searching for both dead and living individuals. Ageing estimations typically model the biological profile, which can be compared to missing persons. The main goals of this current study were to construct ageing trajectories for adult human faces of both sexes and evaluate sexual dimorphism in relation to static allometry. Our study was based on the analysis of three-dimensional facial surface models of 194 individuals 20-80 years of age. The evaluation consisted of a dense correspondence analysis of facial scans and multivariate statistics. It was shown that both age and sex have a significant influence on facial form and shape. Male features included a longer face, with more protruded foreheads, eyebrow ridges and nose, including the region under the upper lip and mandible region, but more retruded cheeks compared to females. Ageing in both sexes shared common traits, such as more pronounced roundness of the face (rectangular in males), decreased facial convexity, increased visibility of skin folds and wrinkles connected with the loss of skin elasticity, and soft tissue stretching, especially in the orbital area and lower face; however, male faces exhibited more intense ageing changes. The above-mentioned sexual dimorphic traits tended to diminish in the elderly age category, though overall sexual dimorphism was heightened with age. The static allometric relationships between size and form or shape were similar in both sexes, except that the larger faces of elderly males displayed more intensive ageing changes.

A Quantitative Analysis of Lip Aesthetics: The Influence of Gender and Aging

INTRODUCTION

The quantitative analysis of sexual dimorphism of facial structures may valuably support reconstructive and feminization surgery, thanks to the estimation of metrical thresholds useful for distinguishing male and female traits. This study aims at verifying the metrical characteristics of female and male lips, to provide indications for aesthetic surgery.

METHODS

Thirty healthy Caucasian volunteers (20 men and 20 women) were divided into two groups according to age: 21-34 years and 45-65 years. Arches and the cutaneous (external) and mucosal (internal) labial surfaces were reproduced by stone models, and digitised using a computerised electromechanical instrument. Area, volume and thickness were measured separately for the upper and lower lips, and compared between sexes and ages by Student's t test, and multinomial logistic regression.

RESULTS

All lip measurements were larger in males than in females; upper lip thickness best divided males from females, adopting a 9.5-mm threshold (percentage of correct diagnosis: 85 %). Young subjects always showed higher measurements than old subjects; lower lip thickness provided the highest percentage of correct age diagnosis (85 %, adopting a 13.8-mm threshold).

CONCLUSION

This study provides novel thresholds that may contribute to the assessment of adequate reconstruction of lips in aesthetic surgery.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .