The Relationship between Age and Facial Asymmetry:

Chewing Side Preference, Facial Asymmetry and Related Factors in the Northern Finland Birth Cohort 1986

OBJECTIVE

The aim of this study was to find out how the preferred chewing side (PCS) affects facial asymmetry, what kind of factors affect PCS, and whether there are differences in facial asymmetry between symmetrical and asymmetrical masticators.

MATERIAL AND METHODS

The study included 748 subjects (females n=452, males n=296) born in 1985-1986 in Northern Finland (Northern Finland Birth Cohort 1986, NFBC 1986). Subjects' faces were captured in facial 3D images with stereophotogrammetry technology, and they filled in a questionnaire concerning oral health. A comprehensive dental examination was done by a dentist. Subject´s chewing side preference was studied by chewing a piece of paraffin, cotton roll or parafilm. Asymmetry was measured from 3D images with different asymmetry measurements and facial landmarks.

RESULTS

Reduced number of teeth on contralateral side affects PCS (OR = 2.44 in the case of one tooth is missing). Being female increased the whole face and lower face symmetry (p values <0.001-0.824). Self-reported TMD pain has an effect on the sidedness of the chin; there is more pain in the larger side of the chin (OR = 9.45). Different chewing materials had no significant effect on the proportion of chewing sides.

CONCLUSIONS

Females have a more symmetrical face compared to males. PCS does not have a statistically significant effect on facial asymmetry, but the variable affecting PCS itself is extracted teeth.

New Aesthetic Unit (NAU) Method: A Comprehensive Method Based on Accurate Anatomical Assessment and Precise Multilayering Panfacial Treatment for Hyaluronic Acid Fillers

BACKGROUND

Recent progress in anatomy enables a more sophisticated approach to treat patients with facial aesthetic concerns (PFAC) with HA fillers. Furthermore, advances in rheology have offered a range of HA fillers with different biomechanical properties adapted to different indications.

METHODS

Based on recent anatomical and rheological progresses, the author has developed a new methodology that couples an accurate patient assessment tool and a panfacial precise treatment instrument. In the presented method, the face is divided into 6 units called New Aesthetic Units (NAU). NAUs are classified on the extent of volume deficiency and asymmetry, ranging from none to moderate to severe deficiencies. After discussion with the patient regarding the assessment findings, a customized treatment plan, including timelines and number of sessions, is recommended. The modalities of the treatment are exhaustively described for each NAU based on multilayering, best practice medicine, and expert consensus available in the literature.

RESULTS

Before-and after-case studies are presented to illustrate how the NAU method is used in routine practice for the treatment of two patients with HA fillers.

CONCLUSION

The NAU method is not only a practical and accurate roadmap for the assessment and treatment of PFAC with HA fillers, but also facilitates communication between injectors and patients and data analysis.

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 .

Age-related changes in cheek skin movement: A case study of Japanese women

BACKGROUND

The majority of conventional studies on skin aging have focused on static conditions. However, in daily life, the facial skin we encounter is constantly in motion due to conversational expressions and changes in facial expressions, causing the skin to alter its position and shape, resulting in a dynamic state. Consequently, it is hypothesized that characteristics of aging not apparent in static conditions may be present in the dynamic state of the skin. Therefore, this study investigates age-related changes in dynamic skin characteristics associated with facial expression alterations.

METHODS

A motion capture system measured the dynamic characteristics (delay and stretchiness of skin movement associated with expression) of the cheek skin in response to facial expressions among 86 Japanese women aged between 20 and 69 years.

RESULTS

The findings revealed an increase in the delay of cheek skin response to facial expressions (r = 0.24, p < 0.05) and a decrease in the stretchiness of the lower cheek area with age (r = 0.60, p < 0.01). An increasing variance in delay and stretchiness within the same age group was also observed with aging.

CONCLUSION

The findings of this study revealed that skin aging encompasses both static characteristics, such as spots, wrinkles, and sagging, traditionally studied in aging research, and dynamic aging characteristics of the skin that emerge in response to facial expression changes. These dynamic aging characteristics could pave the way for the development of new methodologies in skin aging analysis and potentially improve our understanding and treatment of aging impressions that are visually perceptible in daily life but remain unexplored.

Does facial asymmetry vary between subjects of different age groups? A 3D stereophotogrammetry analysis

This study was aimed to assess whether facial asymmetry increases with age and to examine potential gender differences using 3D stereophotogrammetry. A prospective cross-sectional study was performed. 3D photographs were acquired from 600 control subjects, 300 male, 300 female, and were stratified into 15 different age groups ranging from 0 to 70+. The 3D photographs were postprocessed and mirrored. The original and mirrored faces were surface-based matched using an iterative closest point algorithm. The primary outcome variable, facial asymmetry, was evaluated by calculating the absolute mean distance between the original and mirrored images. The primary predictor was age. Pearson's correlation was used to assess the correlation between facial asymmetry and age. The average overall facial asymmetry was 0.72 mm (SD 0.72 mm; range 0.25 - 3.04 mm). Mean facial asymmetry increased significantly with age, from 0.45 mm in the age group of 0-4 years to 0.98 mm in the age group of 70+ (p<0.001). Facial asymmetry was positively correlated with age (Pearson's r = 0.55; p<0.001). Male subjects were significantly more asymmetric compared to females, 0.77 mm and 0.67 mm, respectively (p<0.001). This study indicates that facial asymmetry significantly increases with age and is significantly larger in males than in females.

Periocular Asymmetry Index in Caucasian Populations Using Three-dimensional Photogrammetry Assessment

OBJECTIVE

To quantitatively assess the periocular asymmetry and investigate its sex and age-related differences in a Caucasian population using three-dimensional (3D) stereophotogrammetry.

METHOD

Standardized 3D photos of the periocular region of 301 Caucasians were taken using the VECTRA M3 3D Imaging System. Standardized landmarks were positioned, and data measurements in the periocular region were obtained from these images using VAM software and assessed using intraclass correlation coefficients (ICC) for reliability. Absolute differences and asymmetry index between the right and the left periocular region were calculated with a focus on gender and age-related differences.

RESULT

Fissure height asymmetry was positively correlated with age (p < 0.01). Furthermore, reflex distance asymmetry was positively correlated with age in the elderly group (p < 0.05). Absolute differences of upper eyelid crease were 0.65 ± 0.79 mm for females and 0.90 ± 0.94 mm for males (p < 0.05). In the elderly group, the absolute differences of reflex distance were 0.664 ± 0.471 mm for males and 0.470 ± 0.408 mm for females (p < 0.05), while the absolute differences of fissure height were 0.619 ± 0.469 mm and 0.436 ± 0.372 mm, respectively (p < 0.05). All measurements had an inter-rater ICC and intra-rater ICC between 0.761 and 0.957.

CONCLUSION

Periocular asymmetry is more prominent in older and male people. 3D photogrammetry is a reliable tool to detect periocular asymmetry and might provide an accurate and effective reference for periocular cosmetic, plastic, and reconstructive surgery in the clinical routine.

LEVEL OF EVIDENCE I

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 .

Preoperative Eyelid and Eyebrow Asymmetry: A Potential Pre-Operation Inform Consent Option: A Descriptive Cross-Sectional Study

Background

We aimed to determine the prevalence of pre-existing asymmetry in our patients and investigate the impact of age and sex on upper facial asymmetry.

Methods

We collected images from 155 patients who were undergoing upper eyelid blepharoplasty and MRD1 (marginal reflex distance 1), TPS (tarsal plate show), and BFS (brow fat span) measurements were extracted by ImageJ software. The relationship between asymmetry and age and gender was assessed by comparing the mean differences of these metrics. A generalized linear model (GLM) was used to compare the outcomes of the study. P-value < 0.05 was considered significantly different in all tests.

Results

Pre-operative asymmetry was present in 112 (72%) patients. Among the cases, 61 (39%), 40 (26%), and 24 (15.5%) patients had more than 1mm of asymmetry in BFS, TPS, and MRD1, respectively. Males under 50 years old had the most asymmetry in the preorbital area. Comparing men under 50 years old with the other groups showed that the mean ± SD of absolute differences of TPS was significantly higher in this group (all P< 0.00), but pairwise comparison for MRD1 and BFS indicated no significant correlation between age, gender, and the mean asymmetry of these parameters (overall test P = 0.70 for MDR1 and P = 0.45 for BFS).

Conclusion

Most patients have asymmetry before surgery without being aware of it. Awareness of this asymmetry and the relationship between facial asymmetry and age and gender is essential to prevent dissatisfaction due to the probable post-operative asymmetry and unrealistic expectations.

Facial asymmetry and midsagittal plane definition in 3D: A bias-free, automated method

Symmetry is a fundamental biological concept in all living organisms. It is related to a variety of physical and social traits ranging from genetic background integrity and developmental stability to the perception of physical appearance. Within this context, the study of human facial asymmetry carries a unique significance. Here, we validated an efficient method to assess 3D facial surface symmetry by best-fit approximating the original surface to its mirrored one. Following this step, the midsagittal plane of the face was automatically defined at the midpoints of the contralateral corresponding vertices of the superimposed models and colour coded distance maps were constructed. The method was tested by two operators using facial models of different surface size. The results show that the midsagittal plane definition was highly reproducible (maximum error < 0.1 mm or°) and remained robust for different extents of the facial surface model. The symmetry assessments were valid (differences between corresponding bilateral measurement areas < 0.1 mm), highly reproducible (error < 0.01 mm), and were modified by the extent of the initial surface model. The present landmark-free, automated method to assess facial asymmetry and define the midsagittal plane of the face is accurate, objective, easily applicable, comprehensible and cost effective.

Analyzing Facial Asymmetry in Alzheimer's Dementia Using Image-Based Technology

Several studies have demonstrated accelerated brain aging in Alzheimer's dementia (AD). Previous studies have also reported that facial asymmetry increases with age. Because obtaining facial images is much easier than obtaining brain images, the aim of this work was to investigate whether AD exhibits accelerated aging patterns in facial asymmetry. We developed new facial asymmetry measures to compare Alzheimer's patients with healthy controls. A three-dimensional camera was used to capture facial images, and 68 facial landmarks were identified using an open-source machine-learning algorithm called OpenFace. A standard image registration method was used to align the three-dimensional original and mirrored facial images. This study used the registration error, representing landmark superimposition asymmetry distances, to examine 29 pairs of landmarks to characterize facial asymmetry. After comparing the facial images of 150 patients with AD with those of 150 age- and sex-matched non-demented controls, we found that the asymmetry of 20 landmarks was significantly different in AD than in the controls (p < 0.05). The AD-linked asymmetry was concentrated in the face edge, eyebrows, eyes, nostrils, and mouth. Facial asymmetry evaluation may thus serve as a tool for the detection of AD.

Application of Surgery-First Approach in Treating Skeletal Dentofacial Asymmetry with Orthognathic Surgery

BACKGROUND

Skeletal dentofacial asymmetry decreases patient's attractiveness by deteriorating symmetry of facial appearance which is of great significance to individuals. Surgery-first orthognathic approach manifests its advantages of shortening treatment time and improving patient's quality of life. However, current literature on surgery-first approach mainly focuses on treating prognathism, overlooking its efficacy in improving facial symmetry of skeletal dentofacial asymmetry patients. This study aimed to assess SFA's efficacy in improving facial appearance by analyzing morphological features of asymmetric bone and facial soft tissue in a three-dimensional manner.

METHODS

Thirty-four patients who received orthognathic surgery in a surgery-first fashion were included. Based on three-dimensional CT reconstruction, bilateral preoperative morphological features and postoperative symmetry of hard tissue were compared respectively. Efficacy of facial soft tissue symmetry restoration was evaluated using root mean square deviation (RMSD).

RESULTS

Asymmetric features mainly located in menton, mandibular body length, angulation between ramus and midsagittal plane (MSP), distance between gonion and MSP and so on, which were significantly restored after the whole treatment. RMSD of facial soft tissue surface were significantly declined after the treatment and prognathism was corrected simultaneously if existed.

CONCLUSIONS

Surgery-first orthognathic approach is proved to be capable of treating skeletal dentofacial asymmetry effectively and efficiently.

Evaluation of facial soft tissue asymmetric changes in Class III patients after orthognathic surgery using three-dimensional stereophotogrammetry

The aim of this study was to investigate changes in facial soft tissue asymmetry over time after orthognathic surgery in Class III patients using three-dimensional stereophotogrammetry. The study included 101 patients with a skeletal Class III malocclusion (72 female, 29 male; age range 19-53 years, mean age 28.6 years) who underwent orthognathic surgery. The minimum follow-up was 12 months. Three-dimensional photographs were acquired using the 3dMDtrio stereophotogrammetry system, and 21 anthropometric landmark positions were evaluated at three time points: before surgery (T0), 6 months (T1) and 12 months (T2) after surgery. Facial asymmetry was assessed and classified as follows: 0-2 mm, mild; 2-5 mm, moderate;> 5 mm, severe. The average distance for whole face asymmetry differed between T0 (median 0.76 mm) and T1 (median 0.70 mm); however, there was no statistically significant difference at any time point. The chin volume asymmetry score differed significantly between T0 (median 1.11 mm) and T1 and T2 (median 1.08 mm for both; P < 0.001 and P = 0.001, respectively), but not between T1 and T2 (P = 0.061). The study findings indicate that the asymmetry of the facial soft tissues has the potential to return after 6 months, without reaching the baseline.

The effect of observation angles on facial age perceptions: A case study of Japanese women

Most conventional aging research has limited its approach concerning the head and face shape and skin condition to the frontal face. However, in our daily lives, we observe facial features from various angles, which may reveal or obscure aging features that could only be identified under limited conditions in the past. This study systematically investigates the effect of facial observation angles-specifically, of horizontal and vertical angles-on age impression. A total of 112 Japanese women aged 20-49 years participated as observers who evaluated the age impressions of 280 Japanese women aged 20-69 years. A two-way analysis of the variance of the age impression score was conducted for two factors: observation angle (five angles with yaw and pitch directions) and age group (five ages, from the 20s to the 60s). The results reveal that, as compared with frontal observation, the perceived age tended to decrease with the facial observation angles and that the effect of the angle on perceived age decreased with increasing age, especially for the profile face. Understanding the effect of the facial observation angle on age impression and clarifying the characteristics of the face and skin not perceived in the frontal face will provide useful knowledge to make people look youthful, look more beautiful, and be happier in all aspects of their lives.

Quantitative analysis of soft tissue sagging after lateral midface fractures: A 10-year retrospective study

BACKGROUND

Lateral midface fractures occasionally require open reduction and internal fixation to restore function and facial symmetry. However, some patients retain facial asymmetry despite undergoing surgery due to hard tissue displacement or soft tissue sagging. This study aimed to determine the influence of soft tissue sagging on the postoperative facial symmetry.

METHODS

We examined the medical records of 590 patients who underwent planned plate removal after lateral midface or zygomatic bone fractures. After applying the inclusion and exclusion criteria, we analyzed 106 cases of lateral midface fractures for hard tissue displacement and soft tissue sagging using pre- and postoperative radiological imaging and postoperative face scanning.

RESULTS

We observed significantly larger soft tissue sagging (p &lt; 0.001) and hard tissue displacement (p = 0.006) on the fractured side than on the non-fractured side. There was no correlation between differences in the soft tissue sagging and those in the hard tissue displacement (|rho|=0). Linear regression analysis showed no statistical influence of sex or age group on the soft tissue sagging and hard tissue displacement.

CONCLUSION

Therefore, we recommend treating soft tissue sagging as a discrete aspect of midfacial fracture treatment to achieve optimal postoperative facial symmetry. From a clinical perspective, we recommend better soft tissue management during open fracture treatment than focusing mainly on the reduction of bony hard tissues.

Anthropometric fluctuating asymmetries in living humans through the eyes of an anthropologist

There are many environmental and genetic factors that disrupt the stable structure of development in organisms. Although the strength of these vary, they leave certain signs in the body structure. Fluctuating asymmetry is a widely used population-level index of developmental instability, developmental noise, and robustness. Many bilateral traits are used in fluctuating asymmetry studies in humans. These traits include dermatoglyphics, limb lengths and widths, bilateral facial characters, and teeth. In this review, I evaluate the measurement methods of many bilateral anthropometric characters, taken from the bodies of living individuals with classical digital calipers.

Evaluation of the relationship between nasal septal deviation and development of facial asymmetry with anthropometric measurements depending on age

AIM

It was aimed to determine the change of facial asymmetry resulting from nasal septal deviation (SD) depending on age, gender, degree of deviation and the affected area besides the effect of SD on somatotype and craniofacial morphology.

MATERIALS AND METHODS

171 volunteers (90 males, 81 females), 27 individuals aged 9-13, 44 individuals aged 14-18, 44 individuals aged 19-23 and 56 individuals in control group participated in the study conducted in otorhinolaryngology polyclinic.11 photometric, 16 anthropometric measurements were taken from the participants.

RESULTS

SD affects facial asymmetry formation, although not statistically significant compared to healthy individuals asymmetry rates (p˃0.05). It was determined that the degree of SD affected asymmetry only between the ages of 14-18 (in adolescence) and the development of asymmetry in all SD patients was not statistically dependent on age and gender (p˃0.05). Photometric measurements demonstrated asymmetries in horizontally-extending parameters of 1/3 middle part of face. There was no statistically significant difference in the cranial anthropometric measurements of the upper and lower 1/3 of the face compared to the control group (p˃0.05). The order of the most asymmetrical parameters is Alare-Zygion, Alare-Subnasale, Cheilion-Gonion, Exocanthion-Cheilion, Midsagittal plane-Zygion, Zygion-Cheilion, Zygion-Gonion, Subalare-Cheilion, Glabella-Exocanthion. In all participants were determined that endomorph somatotype was dominant in female and mesomorph somatotype was dominant in male besides SD did not affect somatotype and somatotype did not alter with age.

CONCLUSION

The development of facial asymmetry due to SD is not affected by age and gender furthermore SD does not affect craniofacial asymmetry and somatotype.

Trends in horizontal periocular asymmetry

OBJECTIVE

To determine whether there is laterality predominance in the horizontal dimensions of the periocular region.

DESIGN

Retrospective study.

PARTICIPANTS

Patients >18 years of age who presented to a single academic ophthalmology department. Exclusion criteria included history of facial trauma or surgery, aesthetic injections, or other periocular-altering processes.

METHODS

Standardized digital photographs were obtained, and periocular structures were measured with Image J software. The midline was defined as the midpoint between the medial canthi, and the distances measured include midline to medial canthus, pupil centre, lateral canthus, and lateral zygoma. The palpebral fissure width was calculated as the distance between the lateral canthus and medial canthus. Data analysis was done for the full cohort and subsequently according to patient-identified gender.

RESULTS

Periocular structures were measured in 83 patients (50 female and 33 male) with a mean age of 57.0 ± 16.2 years (range, 22-84 years). Right-sided predominance was found to be increasingly significant for the following variables: midline to pupil centre (31.34 mm vs 31.08 mm, p < 0.01), midline to lateral canthus (42.57 mm vs 42.23 mm, p < 0.005), and midline to lateral zygoma (65.70 mm vs 64.01 mm, p < 0.001).

CONCLUSIONS

Photographic analysis of adults with no periocular-altering history demonstrates that there is a right-sided predominance in the horizontal dimension of the midline to the pupil, lateral canthus, and zygoma with increasing significance. Asymmetry of horizontal periocular measurements was more prevalent in males.

The Effect of Sleep Position Preference on Eyelid and Eyebrow Symmetry

PURPOSE

To investigate the relationship between sleep position preference and eyebrow and eyelid position and degree of upper eyelid dermatochalasis.

METHODS

A prospective study evaluating the impact of sleep position on facial asymmetry was conducted at an academic ophthalmology department. Eligibility criteria included the absence of periocular-altering trauma or surgery, contact lens use, or other periorbital disease processes. Patients reported their sleep position preference on a questionnaire. Standardized digital photographs of patients were obtained, and Image J software was used for measurements and converted into millimeters based on a standard corneal limbus-to-limbus ratio. Upper and lower eyelid position, upper eyelid dermatochalasis, and eyebrow position were assessed by the following image-derived measurements: marginal reflex distance 1 (iMRD1), marginal reflex distance 2 (iMRD2), tarsal platform show (iTPS), and central brow position (iBP). These results were compared with the patient reported sleep position preference to determine correlation.

RESULTS

Seventy-one patients were enrolled and reported the following sleep position preferences: 28 (right), 24 (left), 13 (both), and 6 (supine). Patients with a right- or left-sided preference demonstrated lower iMRD1 measurements for the preferred sleep side (p < 0.0004) with no other significant difference in periorbital measurements. A larger degree of upper eyelid height (iMRD1) asymmetry was observed among patients with a sleep side preference.

CONCLUSION

Patients with a predominant sleep side preference demonstrate a significant increase in ipsilateral upper eyelid asymmetry and an inferior upper eyelid position on the sleep side. There were no differences noted in lower eyelid position, central eyebrow position, or amount of upper eyelid dermatochalasis.

Studying factors influencing facial developmental instability

BACKGROUND

Developmental instability is a component of non-genetic variation that results from random variation in developmental processes. It is considered a sensitive indicator of the physiological state of individuals. It is reflected in various ways, but in this study we focussed on its reflection in fluctuating asymmetry (FA) and morphological integration.

AIM

To assess how, if at all, variations of facial morphology mirror developmental instability across childhood with respect to sex, growth rate and socioeconomic/environmental factors.

SUBJECTS AND METHODS

A set of 210 three-dimensional facial models (of children aged between 6.3 and 14.3 years) originating from the FIDENTIS 3D Face Database was subjected to landmark-based methods of geometric morphometrics to quantify the degree of facial asymmetry and facial morphological integration. In addition, the association with age, sex, and socioeconomic factors was assessed.

RESULTS

Our results showed a nonlinear increase of FA with age up to the age of 14 years. The pattern of sex-related variants in facial FA differed in relation to age, as girls exhibited higher values of FA than boys up to the age of 9 years. We found that a signal of modularity based on functional demands and organisation of the face is of particular importance. Here, girls exhibited higher morphological covariation among modules. During more rapid adolescence-related growth, however, covariation among modules at the asymmetrical level decreased in both sexes.

CONCLUSION

We can conclude that facial morphology was shown to be strongly integrated, particularly until adolescence. This covariation can facilitate an increase of FA. In addition, the results of this study indicate there is a weak association between socioeconomic stress and facial asymmetries. In contrast, sex and growth rate are reflected in developmental instability.

Brief Report: Facial Asymmetry and Autistic-Like Traits in the General Population

Atypical facial morphology, particularly increased facial asymmetry, has been identified in some individuals with Autism Spectrum Conditions (ASC). Many cognitive, behavioural and biological features associated with ASC also occur on a continuum in the general population. The aim of the present study was to examine subthreshold levels of autistic traits and facial morphology in non-autistic individuals. Facial asymmetry was measured using three-dimensional facial photogrammetry, and the Autism-spectrum Quotient was used to measure autistic-like traits in a community-ascertained sample of young adults (n = 289). After accounting for covariates, there were no significant associations observed between autistic-like traits and facial asymmetry, suggesting that any potential facial morphology differences linked to ASC may be limited to the clinical condition.

Lateral and Frontal Cephalometric Measurements in a Cohort With Saethre-Chotzen Syndrome

OBJECTIVE

Descriptions of the craniofacial morphology in Saethre-Chotzen syndrome (SCS) are primarily based on case reports or visual assessments of affected families. The aim of this study was to compare cephalometric measurements of the craniofacial skeleton in a cohort of individuals with SCS and age- and sex-matched individuals without craniofacial anomalies.

DESIGN

Retrospective case series.

PATIENTS

Eight girls and 4 boys with SCS (age range, 7.0-19.2 years).

METHODS

Cephalometric measurements were performed using lateral and frontal cephalograms.

RESULTS

Most of the individuals with Saethre-Chotzen syndrome exhibited lower values for SNA, SNB, s-n and s-ar, while their NSL/NL, NSL/ML, NL/ML, and n-s-ba values were higher than the respective mean reference values for healthy individuals. In comparison with age- and sex-matched individuals without craniofacial anomalies, the individuals with SCS showed higher values for the maxillary and mandibular angular measurements, as well as for the menton midline angle.

CONCLUSIONS

This sample of 12 unrelated individuals with SCS is the largest collected to date for cephalometric measurements. We found that the syndrome is associated with bimaxillary retrognathism, posterior maxillary and mandibular inclination, neutral sagittal relation as well as a tendency toward an open vertical skeletal relation, a short and flattened skull base, and facial asymmetry, as compared to individuals without the syndrome.

Biomarkers of fetal conditions: Finger ridge-counts, facial fluctuating asymmetry, and digit ratio (2D:4D)-are they correlated in women?

OBJECTIVES

Fetal environmental conditions are crucial for life-long health. Direct measurements of developmental conditions are limited in humans; thus, several biomarkers of those conditions have been proposed: that is, finger ridge-counts, level of facial fluctuating asymmetry (FA), and digit ratio (2D:4D). Since all of these biomarkers share a similar gestational time of formation, we hypothesize that their values are significantly correlated.

MATERIALS AND METHODS

Data were collected at the Mogielica Human Ecology Study Site in southern Poland among 234 women. Finger ridge-counts, level of facial FA, and 2D:4D have been measured. The two-step analyses included Pearson's correlations of simple values of the biomarkers and correlations of composite variables calculated based on principal component analysis.

RESULTS

We did not find any statistically significant correlations between finger ridge-counts, FA, and 2D:4D in women. Similarly, we did not observe any correlations between three composites created from the biomarkers.

DISCUSSION

Our results indicate that there are no relationships between the biomarkers, suggested as proxies of the quality of prenatal conditions, in a single population. This is the first study analyzing three different markers simultaneously. The lack of correlations may indicate that the tested biomarkers reflect, in fact, different environmental conditions, occurring in separate "critical windows" of development, or that the biomarkers are not valid as proxies of developmental conditions.

Oro-facial motor assessment: validation of the MBLF protocol in facial palsy

BACKGROUND

Oro-facial myofunctional praxis assesses the muscular coordination and the degree of motor impairment of the lingual, mandibular and facial muscles necessary for articulation, mimicry and swallowing.

PURPOSE

The objective of this study was to create and validate the MBLF protocol, a French oro-facial myofunctional assessment in order to quantify patient's impairment and to specify the motor and functional deficit for an adapted management.

METHODS

The MBLF was validated against the Sunnybrook Facial Grading System (criterion validity). The construct validity was tested by comparing healthy subjects (n = 102) from patients with facial palsy (n = 60). Internal and external consistency of face symmetry were reported. Normative data was provided.

RESULTS

There was a statistically significant correlation between the MBLF protocol and the Sunnybrook Facial Grading System [F(59) = 310.51, p < 0.001, R² = 0.843]. Significant differences were observed in Student's t test between healthy volunteers and patients with facial palsy [t(74.13) = 14,704, p < 0.001, r = 0.863]. A significant effect of the severity grades of facial palsy on the MBLF_TOTAL scores was found [F(158) = 268.469, p < 0.001]. The more severe the facial palsy, the lower the motor scores were.

CONCLUSION

This MBLF French validation provides a baseline for comparing and quantifying the performance of subjects. The MBLF protocol is valid for assessing facial symmetry in peripheral facial palsy. A prospective study is needed to validate its role in dynamic evaluation of facial palsy.

Serial measurements of facial asymmetry using a wooden tongue depressor in patients with congenital microtia

BACKGROUND AND OBJECTIVES

Congenital microtia may be associated with hemifacial microsomia, but little is known about their correlation and development with aging. Historically, facial asymmetry is easily assessed by observing the occlusal cant using a tongue depressor. We serially measured the occlusal cant in children with microtia to evaluate change in facial asymmetry with growth.

METHODS

Since 2011, frontal photographs of patients with congenital microtia biting a tongue depressor were obtained and reviewed. The occlusal angle was compared between the baseline and final photographs, and the change was compared between cant-positive (>3° at baseline) and cant-negative (<3° at baseline) groups. Multivariate analysis was conducted to determine variables associated with the change in occlusal angle.

RESULTS

Overall, 105 patients were enrolled. With a mean age of 5.4 years at baseline and a mean follow-up of 3.9 years, clinically significant aggravation was observed in 15.4% and 24.2% of cant-positive and cant-negative patients, respectively. Hemifacial microsomia (OR, 4.825; p = 0.005) and occlusal angle at baseline (OR, 0.821; p = 0.045) were associated with aggravation, but the severity of microtia showed no significant association.

CONCLUSIONS

When hemifacial microsomia was present, the occlusal cant seemed to be aggravated in children with microtia at later ages. When the occlusal cant was present without noticeable hemifacial microsomia, some compensation in facial asymmetry was expected. The use of a wooden tongue depressor is a simple, non-invasive, and radiologic hazard-free aid to detect notable change in facial asymmetry in children with microtia.

Three-Dimensional Stereophotogrammetry Assessment of Facial Asymmetry in Facial Palsy

Three-dimensional stereophotogrammetry is not much used in assessing facial palsy and a comprehensive understanding of sources of variation in these measurements is lacking. The present study assessed intra- and interobserver reliability of a novel three-dimensional stereophotogrammetry measurement of facial asymmetry and examined sources of variation in these outcomes. Three photographs (rest, closed mouth smile, and maximum smile) were made of 60 participants, 30 facial palsy patients and 30 control subjects. All images were analyzed twice by 2 observers independently, to determine intra- and interobserver reliability. Variance component analysis was performed to investigate sources of variation in the outcomes. Intraobserver reliability was good with intraclass correlation coefficients ranging from 0.715 to 0.999. Interobserver reliability ranged from 0.442 to 0.929. Reliability of the smile image measurements was not clearly different from the rest images. Variation in measurement results was largely due to the status of a participant, facial palsy versus control. When splitting the sample, the facial expression was a major source of variation. Acceptable reliability of the proposed 3D facial asymmetry measurement was found, in facial palsy patients and control subjects. Interobserver reliability was marked less compared to intraobserver reliability. For follow-up data only one observer should assess 3D stereophotogrammetry measurements.

Outcome of facial contour asymmetry after conventional two-dimensional versus computer-assisted three-dimensional planning in cleft orthognathic surgery

Computer-assisted 3D planning has overcome the limitations of conventional 2D planning-guided orthognathic surgery (OGS), but difference for facial contour asymmetry outcome has not been verified to date. This comparative study assessed the facial contour asymmetry outcome of consecutive patients with unilateral cleft lip and palate who underwent 2D planning (n = 37)- or 3D simulation (n = 38)-guided OGS treatment for correction of maxillary hypoplasia and skeletal Class III malocclusion between 2010 and 2018. Normal age-, gender-, and ethnicity-matched individuals (n = 60) were enrolled for comparative analyses. 2D (n = 60, with 30 images for each group) and 3D (n = 43, with 18 and 25 images for 2D planning and 3D simulation groups, respectively) photogrammetric-based facial contour asymmetry-related measurements were collected from patients and normal individuals. The facial asymmetry was further verified by using subjective perception of a panel composed of 6 blinded raters. On average, the facial contour asymmetry was significantly (all p < 0.05) reduced after 3D virtual surgery planning for all tested parameters, with no significant differences between post-OGS 3D simulation-related values and normal individuals. No significant differences were observed for pre- and post-OGS values in conventional 2D planning-based treatment, with significant (all p < 0.05) differences for all normal individuals-related comparisons. This study suggests that 3D planning presents superior facial contour asymmetry outcome than 2D planning.

The Face of Early Cognitive Decline? Shape and Asymmetry Predict Choice Reaction Time Independent of Age, Diet or Exercise

Slower reaction time is a measure of cognitive decline and can occur as early as 24 years of age. We are interested if developmental stability predicts cognitive performance independent of age and lifestyle (e.g., diet and exercise). Developmental stability is the latent capacity to buffer ontogenetic stressors and is measured by low fluctuating asymmetry (FA). FA is random—with respect to the largest side—departures from perfect morphological symmetry. The degree of asymmetry has been associated with physical fitness, morbidity, and mortality in many species, including humans. We expected that low FA (independent of age, diet and exercise) will predict faster choice reaction time (i.e., correct keyboard responses to stimuli appearing in a random location on a computer monitor). Eighty-eight university students self-reported their fish product consumption, exercise, had their faces 3D scanned and cognitive performance measured. Unexpectedly, increased fish product consumption was associated with worsened choice reaction time. Facial asymmetry and multiple face shape variation parameters predicted slower choice reaction time independent of sex, age, diet or exercise. Future work should develop longitudinal interventions to minimize early cognitive decline among vulnerable people (e.g., those who have experienced ontogenetic stressors affecting optimal neurocognitive development).