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

Facial morphology analysis of Caucasian Brazilian adult women using stereophotogrammetry

This cross-sectional observational study aimed to evaluate and compare facial metrics in women aged 20-65 years using a three-dimensional (3D) stereophotogrammetry system and to establish standardized values for facial metric variations in different age subgroups. This study included 84 Caucasian women divided into two groups based on their age: group 1 (G1) included women aged 20-40 years and group 2 (G2) included women aged 41-65 years. Twenty-one morphometric points on the face were identified, and the facial images were captured using a 3D stereophotogrammetry system, Twenty-three linear measures and 12 angular measures were evaluated, revealing statistically significant differences in 11 linear and 5 angular measures between the groups. In the G2 group, nasal and mouth width, lip philtrum height, Tragus-Nasion and Tragus-Pronasale lengths were increased, along with increased nasofrontal angle, decreased palpebral fissure inclination, and lip vermilion angles. However, palpebral fissure width and height, binocular width, and lip vermilion height were reduced. The aging process in women causes substantial changes in facial features, particularly in the middle and lower thirds of the face. Conversely, no major changes were observed in the upper third of the face. Our study findings provide potential insights for clinicians in developing facial rejuvenation procedures as well as for forensic purposes and surgical planning. The standardized facial metrics values in different age subgroups can guide clinicians in determining appropriate treatment plans for patients seeking facial rejuvenation.

A new perspective: Quantitative description of the Cupid's peak aesthetics essence

OBJECTIVES

The Cupid's peak triangle theory was established to reveal the aesthetics essence of the Cupid's peak through golden ratio deviation to provide quantitative theoretical basis for lip plastic and cosmetic surgery.

MATERIALS AND METHODS

Model the Cupid's peak line on the lip bow ridge and construct expressions for Cupid's peak parameters and their associated triangle theory using the angle circle (AC) and radius circle (RC) of the Cupid's peak line. Calculate and establish functional relationships for Cupid's peak parameters and the concept of the Cupid's peak index (CPI) golden ratio deviation (GRD).

RESULTS

In the Cupid's peak triangle theory, important parameters describing Cupid's peak morphology include Cupid's peak angle (ACp), arc (RCp), the smooth connection point (SI) of the Cupid's peak arc and line, and the CPI. The parameters are interrelated in their functional relationships. ACp determines RCp, the SI point determines the proportion of the Cupid's peak arc to the line, and CPI determines GRD. Cupid's peak parameter ranges in the normal population are as follows: ACp is 109°-160°, RCp is 1.24-0.35 rad, CPI is 0.614-0.508, and GRD is 0.62%-17.85%.

CONCLUSIONS

The Cupid's peak triangle theory reveals the functional relationship between the Cupid's peak parameters and quantifies the aesthetics essence of lip shape.

CLINICAL RELEVANCE

The morphology of the Cupid's peak serves as a tangible manifestation of lip shape aesthetics. This study aims to elucidate the aesthetic essence and general principles of Cupid's peak morphology, offering a quantitative theoretical foundation for lip plastic and cosmetic surgery.

Factors influencing speech improvement following maxillary complete-arch implant-supported restorations: A retrospective study

OBJECTIVE

This study explored factors affecting speech improvement in patients with an edentulous maxilla after the delivery of a complete-arch implant-supported fixed dental prosthesis (IFDP).

MATERIALS AND METHODS

Patients who had received IFDP for edentulous maxilla were enrolled, and various potential speech improvement-related factors were considered, including patient demographics, anterior residual bone volume, preoperative facial features, preoperative acoustic parameters, and adaptation time. Acoustic analysis and perceptual ratings were used to assess three fricatives [s], [f], and [ɕ]. Correlation and regression analyses were conducted to assess the association between changes in fricatives and potential factors (α = .05).

RESULTS

The study included 50 patients (18 females and 32 males, aged 50.62 ± 15.71 years, range 19-76). Significant correlations were found among the change in the center of gravity (ΔCoG) of [s] and anterior residual bone volume, zygomatic implants number and proportion (p < .05). These correlations were largely mirrored in the perceptual score (ΔPS) changes. After controlling for age, sex, preoperative acoustic parameters, and adaptation time, the ΔCoG and ΔPS of fricatives were mainly correlated with the anterior residual bone volume, preoperative acoustic parameters, and adaptation time.

CONCLUSION

Speech improvements post-IFDP delivery are mainly related to preoperative speech characteristics, anterior residual bone volume, and adaptation time. The residual bone volume's impact on consonants varies with specific articulatory gestures. This study provides insights into forecasting speech outcomes following IFDP restoration and provides recommendations and methods for data collection in developing future prediction models.

Comparative 3D Analysis of Lip Rejuvenation: Investigating Effects Before and After Soft-Tissue Filler Compared with Controls

BACKGROUND

The aim of this study was to evaluate changes in lip metrics before and after facial rejuvenation treatment with hyaluronic acid-based fillers and to compare them with those of a control group using stereophotogrammetry (3D).

METHODOLOGY

This study included 63 Caucasian women divided into Group C (<30 years, n=30) and Group H (>30 years, n=33), which was further divided into before (HT0) and after (HT1) lip augmentation with hyaluronic acid (HA). Eleven anthropometric landmarks were identified for linear, angular, and surface area measurements. Three photos were captured in Group C, while Group H had photos taken at T0 and T1. Statistical analysis was conducted using the Shapiro-Wilk test to evaluate normality, the Kruskal-Wallis test and one-way ANOVA. Tukey's post hoc and pairwise comparison tests were performed to analyze differences between variables (P value < 0.05).

RESULTS

There were significant differences between lip width (ChR-ChL) and philtrum width (CphR-CphL) (P<.001). The total heights of the upper (Ls-Li) and lower vermilion lips (Sto-Li) increased, and the heights of the upper (Sn-Ls) and lower (Li-Sl) cutaneous lips decreased. The angles related to the philtrum (ChR-CphR-Ls, P<.001; ChL-CphL-Ls, P<.001) and nasolabial angle (Prn-Sn-Ls) (P<.001) exhibited significant differences. The surface areas of the upper, lower, and total vermilion lip showed significant differences (P<.001). Tukey's test indicated no significant differences in surface area after lip augmentation between the HT1 and C groups.

CONCLUSION

Analysis of lip morphology after a filler procedure revealed a reversal of age-related changes, with increases in vermilion lip height and surface area comparable to those of younger individuals.

LEVEL OF EVIDENCE II

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 .

Automated 3D Perioral Landmark Detection Using High-Resolution Network: Artificial Intelligence-based Anthropometric Analysis

BACKGROUND

Three-dimensional facial stereophotogrammetry, a convenient, noninvasive and highly reliable evaluation tool, has in recent years shown great potential in plastic surgery for preoperative planning and evaluating treatment efficacy. However, it requires manual identification of facial landmarks by trained evaluators to obtain anthropometric data, which takes much time and effort. Automatic 3D facial landmark localization has the potential to facilitate fast data acquisition and eliminate evaluator error.

OBJECTIVES

The aim of this work was to describe a novel deep-learning method based on dimension transformation and key-point detection for automated 3D perioral landmark annotation.

METHODS

After transforming a 3D facial model into 2D images, High-Resolution Network is implemented for key-point detection. The 2D coordinates of key points are then mapped back to the 3D model using mathematical methods to obtain the 3D landmark coordinates. This program was trained with 120 facial models and validated in 50 facial models.

RESULTS

Our approach achieved a satisfactory mean [standard deviation] accuracy of 1.30 [0.68] mm error in landmark detection with a mean processing time of 5.2 [0.21] seconds per model. Subsequent analysis based on these landmarks showed mean errors of 0.87 [1.02] mm for linear measurements and 5.62° [6.61°] for angular measurements.

CONCLUSIONS

This automated 3D perioral landmarking method could serve as an effective tool that enables fast and accurate anthropometric analysis of lip morphology for plastic surgery and aesthetic procedures.

Enhancing Aesthetic Harmony: Comprehensive Anthropometric Lip Measurements in Youthful and Attractive Indonesian Adults for Precision Cosmetic Procedures

Lips are an important part of our perception of beauty, youthfulness and attractiveness. Aesthetic lips, as with the rest of the face, differs according to age, ethnicity and sex. The aim of this study was to evaluate the anthropometric measurements of the lips of young and attractive Indonesian adults. Photographs of faces were taken at an anterior neutral position for 100 participants; 47 men and 53 women volunteered to participate in this study. Seven landmarks were used in this study: stomion (st), sublabiale (sl), subnasale (sn), labiale superius (ls), labiale inferius (li), crista philtre (cp) and chelion (ch). Using these landmarks, lower lip height, upper lip height, philtrum length, upper vermillion height, lower vermillion height, cutaneous lower lip height, philtrum width and mouth width were measured. The results were analysed using independent t-test and Mann-Whitney test. Significant differences in lip size were observed between men and women in all the measurements st-sl (lower lip height), sn-st (upper lip height), sn-ls (philtrum length), li-sl (cutaneous lower lip height), sn-ls/ls-st (philtrum length and upper vermillion height) and ls-li/ch-ch (cutaneous lower lip height and mouth width) with a significance of p=0.003, p=0.007, p<0.001, p=0.05, p=0.005 and p=0.021, respectively. Male lip measurements of ch-ch (overall lip width) and ls-st/li-st (overall lower lip height) were significantly smaller than those of female lips. The lip ratios calculated in this study were congruent with aesthetic parameters reported in other populations. This study suggests that the same measurement standards cannot be used on different populations, but these ratios may offer a better framework for precision cosmetic procedures. We believe that the results obtained in this study on lip anthropometry will help in optimising the standard values that can be used for the Indonesian population aged 20 to 35 years.

Image-based investigation of lip aging features in a large number of Korean women

BACKGROUND

The lips play a significant role in shaping facial aesthetics. Due to the distinct attributes of lips in contrast to other facial skin, a unique approach is imperative for managing lip aging. We analyzed lip characteristics (morphology, wrinkles, and color) to investigate visual changes and distinctive attributes of aging lips.

METHODS

By utilizing image data processing methods, including facial landmark detection, pattern recognition, and color quantification, we extracted 11 lip characteristic indices (four morphological indices, four wrinkle indices, and three color indices) from high-resolution images of 1000 Korean women aged 20-69. Correlation tests were conducted to assess the relationship between lip characteristic indices and age, and also between lip morphological and wrinkle indices.

RESULTS

Lip height significantly decreased, while lip width and lip ratio (lip width divided by the sum of the upper and lower lip height) significantly increased with aging. Lip wrinkles significantly increased with aging, whereas lip colors (redness and yellowness) decreased. The lip wrinkle indices, which are segmented for the first time in this study, exhibited significant correlations with lip width, and three of them additionally were correlated with lip ratio (p < 0.05). The results imply such morphological changes can be associated with wrinkle formation of human lips.

CONCLUSION

The indices suggested in this study can be used for assessing lip aging characteristics, and the study results can contribute to deeper understanding of lip aging.

Development and Validation of a Comprehensive Perioral Evaluation Method Using Three-Dimensional Stereophotogrammetry

BACKGROUND

The non-invasive three-dimensional (3D) stereophotogrammetry is widely used in anthropometry for medical purpose. Yet, few studies have assessed its reliability on measuring the perioral region.

OBJECTIVES

This study aimed to provide a standardized 3D anthropometric protocol for the perioral region.

METHODS

38 female and 12 male Asians were recruited (mean age 31.6 ± 9.6 years). Two sets of 3D images using the VECTRA 3D imaging system were acquired for each subject, and two measurement sessions for each image were performed independently by two raters. 25 landmarks were identified, and 28 linear, 2 curvilinear, 9 angular and 4 areal measurements were evaluated for intrarater, interrater, and intramethod reliability.

RESULTS

Our results showed high reliability of 3D imaging-based perioral anthropometry by mean absolute difference (0.57 and 0.57 unit), technical error measurement (0.51 and 0.55 unit), relative error of measurement (2.18% and 2.44%), relative technical error of measurement (2.02% and 2.34%), and intraclass correlation coefficient (0.98 and 0.98) for intrarater 1 and intrarater 2 reliability; respectively 0.78 unit, 0.74 unit, 3.26%, 3.06% and 0.97 for interrater reliability; and respectively 1.01 unit, 0.97 unit, 4.74%, 4.57% and 0.95 for intramethod reliability.

CONCLUSIONS

This standardized protocol utilizing 3D surface imaging technologies are feasible and highly reliable in perioral assessment. It could be further applied for diagnostic purpose, surgical planning and therapeutic effect evaluation in clinical practice in relation to perioral morphologies.

LEVEL OF EVIDENCE IV

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 .

Gender- and Age-Related Characterization of Lip Morphology: A Three-Dimensional Analysis in a Chinese Population

BACKGROUND

Establishing facial anthropometric reference values is essential for diagnosis of deformity, assessment of aging, and planning for aesthetic and reconstructive treatment.

OBJECTIVES

This study aimed to provide detailed perioral anthropometric data in relation to sex and age in Chinese persons with a standardized 3-dimensional protocol.

METHODS

Three-dimensional facial photographs were obtained of 60 male and 64 female healthy Chinese participants ages 20 to 35 and 50 to 65 years old, as well as 2 acromegaly patients, with the VECTRA 3D camera. A standardized evaluation was performed to locate 37 perioral landmarks and generate corresponding measurements, including 26 linear distances, 5 ratios, 2 curvatures, 4 areas, and 9 angles. Measurements of different age groups and of different genders were compared, as were measurements of healthy individuals with those of acromegaly patients.

RESULTS

Sex discrepancy was noted in philtrum length, width, and area, lip width, and vermilion and cutaneous upper lip area; these were larger in Chinese males than females. However, vermilion heights were similar in both genders. With age, philtrum and cutaneous upper lip height and area, lip width, and angles related to cupid's bow significantly increased, whereas vermilion height and mouth corner angles decreased, and philtrum width, vermilion areas, and lip protrusion remained unchanged. Compared to healthy Chinese patients, acromegaly patients had a larger value for most measurements. Perioral rejuvenation based on detailed 3-dimensional anthropometry showed good results.

CONCLUSIONS

Chinese males have wider but not thicker lips than females, and aging features thin, flattened, and wide vermilions with a lengthened philtrum in both genders. These data can serve as a reference standard for disease diagnosis, aesthetic procedures, and reconstructive lip surgeries.

LEVEL OF EVIDENCE: 4

In vitro and in vivo validation of a new three-dimensional fringe projection-based device (AEVA-HE) dedicated to skin surface mapping

BACKGROUND

Aging signs are much visible on the surface of the skin that presents different changes: cheeks start to sag, more and deeper wrinkles appear, and pigmentation spots increase. Face diagnostic to recommend products includes assessing cutaneous micro-relief or the micro-depressive network on the face. Furthermore, there is an increasing demand for clinical and instrumental methods to prove the efficacy of anti-aging treatments. As a result, very accurate and sensitive three-dimensional (3D) devices are developed and validated to measure and quantify aging skin and to catch fine anti-aging products acting on wrinkles and fine lines.

METHODS

AEVA-HE, a non-invasive 3D method based on fringe projection technology, is used to robustly characterize the skin micro-relief from a full-face acquisition and from multiple extracted zones of interest. In vitro and in vivo studies are conducted to assess the reproducibility of this system and its precision toward a standard fringe projection system, DermaTOP.

RESULTS

The AEVA-HE successfully measured micro-relief and wrinkles and demonstrated the reproducibility of measurements.  AEVA-HE parameters were found highly correlated to DermaTOP.

CONCLUSION

The present work illustrates the performance of the AEVA-HE device and its dedicated software kit as a precious tool for quantifying the major characteristics of wrinkles appearing with age and thus offers a high potential for assessing the effect of anti-wrinkling products.

Lip Lifting Efficacy of Hyaluronic Acid Filler Injections: A Quantitative Assessment Using 3-Dimensional Photography

The study aimed to compare the volume enhancement and the lifting capacity of two different hyaluronic acid gels for lip injection. Thirty-six Korean female patients were randomized into two groups according to the cross-linking degree of the hyaluronic acid filler injected. Using a fixed injection protocol, patients were injected with 1 mL of hyaluronic acid filler in the lips and followed up at four and 12 weeks after injection. Lip volume, lip projection, and columella–labial angle were measured using a 3-dimensional imaging system at each time point. Follow-up values were compared with baseline. Compared with pre-treatment values, there was a statistically significant increase in mean lip volume and lip projection at four and 12 weeks after injection, with no significant differences between the two groups. Lips injected with hyaluronic acid filler of intermediate cross-link density resulted in more acute angles than lips injected with lightly cross-linked hyaluronic acid. The difference was statistically significant at each follow-up time point. No serious complications were observed throughout the study period. Our results imply that in patients who want a prominent upper lip lift, lip injections using hyaluronic acid fillers with intermediate cross-linking density can be a good option due to their lift capacity. The degree of cross-linking may not be a significant determinant of simple lip volume augmentation when other variables are constant.

Three-dimensional facial scanner in the hands of patients: validation of a novel application on iPad/iPhone for three-dimensional imaging

Background

Three-dimensional (3D) photography plays an important role in surgical planning and postoperative evaluation. Commercial 3D facial scanners are expensive, and they require patients to come to the clinics for 3D photography. To solve this problem, we developed an iPad/iPhone application to enable patients to capture 3D images of themselves on their own. This study aimed to evaluate the validity and reproducibility of this novel imaging system.

Methods

3D images were taken on 20 volunteers using the novel imaging system. Twenty-one anthropometric parameters were measured using calipers (direct measurement) and 3D photographs (3D photogrammetry). The results were compared to assess the accuracy and bias of 3D photogrammetry. The reproducibility was evaluated by testing intra- and interobserver reliabilities. Furthermore, 3D virtual models obtained by the novel imaging system and Vectra H1 camera were compared by performing heat map analysis.

Results

The 3D photogrammetric results showed excellent correlations with direct measurements. Most anthropometric parameters did not show statistically significant differences between the two methods. The 95% limits of agreement exceeded 2 mm in some parameters, especially those with large numbers, although their relative error measurements were very small. Intra- and interobserver reliabilities were high enough to ensure good reproducibility. The comparison of 3D models obtained by the novel imaging system and Vectra H1 camera showed that the mean distance and the mean RMS were 0.08 and 0.67 mm, respectively.

Conclusions

The novel 3D facial scanning system is validated to enable patients to take 3D images on their own. The imaging quality of the subnasale region needs further improvement. Future clinical applications include surgical planning, postoperative evaluation, and early diagnosis of diseases that affect facial appearance.

Relationship between lip skin biophysical and biochemical characteristics with corneocyte unevenness ratio as a new parameter to assess the severity of lip scaling

Objective

Lip skin dryness and chapping are major concerns related to lip skin care in many populations. The distinctive features of lip skin, such as the low water‐holding capacity and weak skin barrier, are strongly associated with these problems; however, few studies have examined lip skin characteristics and the mechanisms underlying these issues. This study was conducted to identify the biophysical properties of dry lip skin and molecular targets affecting lip skin physiology.

Methods

Skin hydration, transepidermal water loss and lip skin scaling were evaluated in 40 female subjects. Skin scaling was assessed as a percentage area divided into five categories (G0, G1, G2, G3 and G4) according to the thickness level of tape‐stripped corneocytes. The activities and amounts of proteases, cathepsin D and bleomycin hydrolase were measured as markers for the desquamation process and skin hydration, respectively.

Results

Skin hydration showed a significantly positive correlation with the percentage area of evenly thin corneocytes (G0) and negative correlations with the percentage areas of slightly thick to severely thick corneocytes (G1‐G4). The corneocyte unevenness ratio (CUR) was calculated by dividing the sum of the G1, G2, G3 and G4 values with the G0 value. The CUR was significantly negatively correlated with skin hydration, suggesting that CUR is a new parameter representing the severity of lip scaling. Subjects with lower hydration and higher CUR had higher bleomycin hydrolase activity and lower cathepsin D activity, respectively, than subjects with higher hydration and lower CUR.

Conclusion

Our study revealed a correlation between lip skin hydration and severity of lip scaling and verified the association of protease activity with the hydration and chapping state of lip skin. These observations provide a basis for further studies of the persistent problem of lip skin dryness and chapping.

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.