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Abstract

Knowledge of facial ageing is important in forensic facial approximation and photo identification. Previous studies mostly investigated facial ageing in European faces, and this research therefore aims to provide data on patterns of facial ageing in an African sample. One hundred eighty-nine black South African males aged 20 years and older were photographed in anterior and lateral views. Facial images were captured in a consistent position by using a Canon EOS 1300D camera and 18- to 55-mm EFS lens. Thirty individuals per decade were included, with the 80+ age category being limited to only nine participants. A facial ageing scoring system, based on previous research, was constructed for non-metric age changes such as appearance of wrinkles and sagging around the orbital area. Metric age changes such as ear lengthening and lip thinning were investigated separately. Results indicate that the ageing process in black South Africans has both similarities and differences to senescence described for European populations. Although most ageing features showed unidirectional change during time, these changes often occurred at a variable rate. Some features did not show a clear change with increasing age - these include mouth width increase, nasal elongation, nasal tip dropping, ear width increase and ear length increase. In addition to the age-feature correlations, an average face per decade was developed using Abrosoft FantaMorph Deluxe software. This provides a visual approximation of male South African faces captured at a single moment in time, as an aid for craniofacial depictions and facial image ageing in forensic practise.

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... 8 The vermilion height to mouth width ratio was larger in females than in males, and decreased with age; the total lip height and lip volumes were however significantly larger in males than in females. In a study on an adult South African male sample by Schmidlin et al. 17 , the upper and lower lip dimensions was found to similarly reduce with age, but the lip height dimensions were consistently greater than in Sforza et al.'s 8 European sample. ...
... This was similarly identified by Schmidlin et al. 17 when investigating facial ageing patterns in black South African males, and comparing results to an Italian sample taken from Sforza et al. 8 . It is generally agreed that the prognathism typical to individuals of Sub-Saharan African origin is accompanied by thicker lips 16,30 , but the exact relationship between prognathism and lip thickness is not clear. ...
... The weak relationship between incisor and lip heights also suggested that the canon employed by Gerasimov 16 13,15,17,18 Differences between the sexes in the black population included greater lip heights, central incisor heights and root lengths in males, which is comparable to several previous studies on other population groups. [12][13][14][15] White males and females did not differ significantly regarding lip heights, central incisor heights and root lengths, which was similarly identified in only two existing studies. ...
... 8 The vermilion height to mouth width ratio was larger in females than in males, and decreased with age; the total lip height and lip volumes were however significantly larger in males than in females. In a study on an adult South African male sample by Schmidlin et al. 17 , the upper and lower lip dimensions was found to similarly reduce with age, but the lip height dimensions were consistently greater than in Sforza et al.'s 8 European sample. ...
... This was similarly identified by Schmidlin et al. 17 when investigating facial ageing patterns in black South African males, and comparing results to an Italian sample taken from Sforza et al. 8 . It is generally agreed that the prognathism typical to individuals of Sub-Saharan African origin is accompanied by thicker lips 16,30 , but the exact relationship between prognathism and lip thickness is not clear. ...
... The weak relationship between incisor and lip heights also suggested that the canon employed by Gerasimov 16 13,15,17,18 Differences between the sexes in the black population included greater lip heights, central incisor heights and root lengths in males, which is comparable to several previous studies on other population groups. [12][13][14][15] White males and females did not differ significantly regarding lip heights, central incisor heights and root lengths, which was similarly identified in only two existing studies. ...
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INTRODUCTION: The South African Police Service frequently relies on craniofacial approximation and superimposition to assist in identifying unknown deceased individuals. Standards to estimate lip height are however limited. Findings from this study share medical applications. Aims and objectives: Establish reliable standards for estimating lip height using dentoskeletal measurements. METHODS: Cone-beam CTs comprising 124 black and 39 white southern African adults were assessed. A series of dimensions were recorded using a DICOM viewer with an inbuilt measuring tool. Relationships between hard tissue structures (maxillary, mandibular and total central incisor heights, their corresponding root lengths, face height (N-Gn), and nose height (N-Sn)) and respective overlaying soft tissues (upper, lower and total lip heights) were evaluated. RESULTS AND CONCLUSIONS: Statistically significant differences were observed between population, sex and age groups. A selection of regression equations to estimate lip height was calculated that included population, sex and approximate age (20-39 and 40+ years) for improved goodness-of-fit (r²-value). Regression models using face height produced the strongest multiple correlation (r-value) and goodness-of-fit (r²-value). Validation testing indicated that regression models often improved upon mean measurements, while offering a degree of individuality that mean values do not.
... Equally important, a sample size of as few as 12 individuals was sufficiently representative of each age group. A pilot study by a different research group also used facial averaging to assess facial aging changes [198]. That study included 189 black South African men ranging in age from 20 to 100 years old, with 30 participants in each decade-long age group from 20 to 29 years old up to 70 to 79 years old and nine participants in the 80+ age group. ...
... Two different computer programs for facial averaging that were used in previous research [31,188,198] were used to create the facial averages in this study. ...
... FaceMixer (https://www.abrosoft.com), the commercial facial averaging software used in the Schmidlin et al. study discussed above [198], ranges in cost from $29.00 to $99.00 per licensed copy depending on what features are needed. FaceMixer was originally meant to be used mainly for entertainment or commercial animation purposes, and it is relatively user-friendly and intuitive to use. ...
Article
Many characteristics of facial aging are common to all. The age of their onset and which characteristics tend to predominate varies among individuals depending on many factors including their genetic makeup, life experiences, environment in which they live, and the regional, ethnic, or socially perceived group to which they belong. Forensic artists are often asked to provide sketches, 2D or 3D digital renderings, or sculptures representative of how an individual may appear at an older age based on a provided photograph, victim or witness description, and/or cranial remains. The challenge escalates when the subject is a member of a regional, ethnic, or other socially perceived group to which the artist has had little or no exposure. We describe aspects of adult facial aging that are of particular relevance to the forensic artist, applicable software tools, and pertinent facial databases, especially those emphasizing non-white populations. We demonstrate that facial averaging offers two key advantages to the artistic portrayal of facial aging: first, the technique requires relatively small reference databases from groups that may present logistical challenges to collect and second, that a facial average provides a useful representation of the gestalt of the age and ethnicity cohort to which a subject belongs. The artist may use an average along with other available information such as photo reference books, eyewitness descriptions, photos of immediate family members, and cranial structure to guide production of a facial composite drawing, digital age progression, or sculpture of the subject in question.
... Tentative explanations for age-related changes in facial dimensions have included macroscopic factors (i.e., impact of gravity, changes in posture, weight gain) and microscopic factors (i.e., reductions in elastic fibers, skin elasticity and resilience, thinning of the cutis, muscle weakness and reduction, and increase in subcutaneous fat) (40,41). Schmidlin et al. (42), however, studied facial aging in 10-year increments (20-80+ years) using 189 photogrammetric surface scans of black South African males and identified no clear age-related alteration in mouth width. These differences may be related to errors in manually locating the chelions and measuring the mouth width, in the different modes of data collection used (surface scans versus CBCT scans), or a natural difference in the population/ environmental variation between samples. ...
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Standards for estimating mouth width and Cupid’s bow width in craniofacial approximation and superimposition are limited. Currently, the only guideline for mouth width, using direct skeletal references, is a general rule indicating a 75% inter‐canine to mouth width ratio. The philtrum, which closely corresponds to the Cupid’s bow, is said to be equal to the inter‐superior prominences of the maxillary central incisors. This study tested these guidelines against newly generated regression models and mean values. Cone‐beam CT scans of 120 black and 39 white southern African adults were used. Comparative hard and soft tissue measurements were taken using a 3D DICOM viewer. Regression equations accounting population, sex, and approximate age variables (20–39 and 40+ years), utilizing maxillary inter‐canine width to estimate mouth width and maxillary central–lateral incisor junction width to estimate Cupid’s bow width, performed statistically best. The regression models were more reliable than existing standards in validation tests.
... Pitanguy (2000) extended this approach toward lateral views, and both research teams further support most of the above-described soft-tissue patterns regarding eyes, lips, and ears in Brazilian patients of European descent. Schmidlin, Steyn, Houlton, and Briers (2018) obtained similar results in African faces and graphed their values in relation to the work of Sforza and colleagues in Italian faces. They confirmed the overall pattern, notwithstanding absolute thickness differences between the populations at a given age stage. ...
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Objectives Despite variation in lifestyle and environment, first signs of human facial aging show between the ages of 20–30 years. It is a cumulative process of changes in the skin, soft tissue, and skeleton of the face. As quantifications of facial aging in living humans are still scarce, we set out to study age‐related changes in three‐dimensional facial shape using geometric morphometrics. Materials and methods We collected surface scans of 88 human faces (aged 26–90 years) from the coastal town Split (Croatia) and neighboring islands. Based on a geometric morphometric analysis of 585 measurement points (landmarks and semilandmarks), we modeled sex‐specific trajectories of average facial aging. Results Age‐related facial shape change was similar in both sexes until around age 50, at which time the female aging trajectory turned sharply. The overall magnitude of facial shape change (aging rate) was higher in women than men, especially in early postmenopause. Aging was generally associated with a flatter face, sagged soft tissue (“broken” jawline), deeper nasolabial folds, smaller visible areas of the eyes, thinner lips, and longer nose and ears. In postmenopausal women, facial aging was best predicted by the years since last menstruation and mainly attributable to bone resorption in the mandible. Discussion With high spatial and temporal resolution, we were able to extract a shared facial aging pattern in women and men, and its divergence after menopause. This fully quantitative three‐dimensional analysis of human facial aging may not only find applications in forensic and ancient human facial reconstructions, but shall include lifestyle and endocrinological measures, and also reach out to studies of social perception.
... For age progression, photographs of siblings, parents, or other genetically related people may serve as guides to the final facial structure [3, 218,219]. For computer-quantified methods, faces are morphed by age using average patterns of facial appearance [221][222][223][224][225] or more individually tailored growth trajectories-for example, delineated by regressions in principal component space [164,220,226]. Age progression/ regression methods have been employed for both 2D [3, [218][219][220][221] and 3D images [164,222,226]. ...
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Facial imaging is a term used to describe methods that use facial images to assist or facilitate human identification. This pertains to two craniofacial identification procedures that use skulls and faces—facial approximation and photographic superimposition—as well as face-only methods for age progression/regression, the construction of facial graphics from eyewitness memory (including composites and artistic sketches), facial depiction, face mapping and newly emerging methods of molecular photofitting. Given the breadth of these facial imaging techniques, it is not surprising that a broad array of subject-matter experts participate in and/or contribute to the formulation and implementation of these methods (including forensic odontologists, forensic artists, police officers, electrical engineers, anatomists, geneticists, medical image specialists, psychologists, computer graphic programmers and software developers). As they are concerned with the physical characteristics of humans, each of these facial imaging areas also falls in the domain of physical anthropology, although not all of them have been traditionally regarded as such. This too offers useful opportunities to adapt established methods in one domain to others more traditionally held to be disciplines within physical anthropology (e.g. facial approximation, craniofacial superimposition and face photo-comparison). It is important to note that most facial imaging methods are not currently used for identification but serve to assist authorities in narrowing or directing investigations such that other, more potent, methods of identification can be used (e.g. DNA). Few, if any, facial imaging approaches can be considered honed end-stage scientific methods, with major opportunities for physical anthropologists to make meaningful contributions. Some facial imaging methods have considerably stronger scientific underpinnings than others (e.g. facial approximation versus face mapping), some currently lie entirely within the artistic sphere (facial depiction), and yet others are so aspirational that realistic capacity to obtain their aims has strongly been questioned despite highly advanced technical approaches (molecular photofitting). All this makes for a broad-ranging, dynamic and energetic field that is in a constant state of flux. This manuscript provides a theoretical snapshot of the purposes of these methods, the state of science as it pertains to them, and their latest research developments.
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The objective of this study was to supply information about: (1) normal sex-related dimensions of mouth and lips (linear distances, ratios, angles, area, volume); and (2) growth changes between childhood and old age. The three-dimensional coordinates of several soft-tissue landmarks on the lips and face were obtained by a non-invasive, computerized electromagnetic digitizer in 532 male and 386 female healthy subjects aged 4-73 years. From the landmarks, linear distances (mouth width, width of the philtrum, vermilion heights of the upper, lower and total lips, total lip height), the vermilion height-to-mouth width ratio, areas (vermilion of the upper, lower and total lip) and volumes (upper, lower, and total lip volume) were calculated and averaged for age and sex. Comparisons were performed by factorial analysis of variance. Mouth width, width of the philtrum, total lip height, and lip volumes were significantly larger in men than in women (p<0.01), increased with age (p<0.001), and had age x sex interactions (p<0.001). Vermilion areas and heights of the lower and total lips progressively increased with age until late adolescence, and then decreased with aging (p<0.001). The vermilion height-to-mouth width ratio was larger in women than in men (p<0.001), and decreased with age (p<0.001). Data collected in the present investigation could serve as a database for the quantitative description of human lip morphology during normal growth, development and aging. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, aging of living and dead persons, personal identification) may also benefit from age- and sex-based data banks.
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Testosterone-dependent secondary sexual characteristics in males may signal immunological competence and are sexually selected for in several species. In humans, oestrogen-dependent characteristics of the female body correlate with health and reproductive fitness and are found attractive. Enhancing the sexual dimorphism of human faces should raise attractiveness by enhancing sex-hormone-related cues to youth and fertility in females, and to dominance and immunocompetence in males. Here we report the results of asking subjects to choose the most attractive faces from continua that enhanced or diminished differences between the average shape of female and male faces. As predicted, subjects preferred feminized to average shapes of a female face. This preference applied across UK and Japanese populations but was stronger for within-population judgements, which indicates that attractiveness cues are learned. Subjects preferred feminized to average or masculinized shapes of a male face. Enhancing masculine facial characteristics increased both perceived dominance and negative attributions (for example, coldness or dishonesty) relevant to relationships and paternal investment. These results indicate a selection pressure that limits sexual dimorphism and encourages neoteny in humans.
Article
For measurements to be accurate and precise, measurement errors should be small. In the anthropometry and craniofacial identification literature, four methods are commonly used for assessing measurement error: Pearson's product moment correlation coefficient (r), intra-class correlation coefficients (ICC), statistical significance tests (often reported by P-values) and the technical error of measurement (TEM; also known as Dalberg's error/ratio). In this paper, the performance of all four of these statistics were evaluated using maximum cranial lengths (g-op) from Howells (n=2524), by duplicating the dataset and mathematically adding known degrees of error to the second set. This was repeated under a broad array of trials (2000 total) each with slightly different amounts of error simulation to comprehensively assess the four error metrics in terms of descriptive power and utility, using the same data for each of the four error assessment methods. Data simulations included the addition of random and systematic errors of different sizes with absolute differences ranging from 1 to 50mm (or in relative terms, 28% of the original measurement). Two sample sizes (n=25 and 2524 individuals) were explored and all analyses were conducted in R. P-values from Student's t-tests only showed significant differences (P<0.05) for the larger sample size when the error was systematic. Small samples, and/or any with random error, did not yield low or significant P-values (P<0.05). When raw differences were <4mm for 95% of the sample (n=2524), the ICC and r were high (>0.97) and remained so even after tripling the error, such that 95% of the sample possessed raw differences up to 12mm (r=0.8). In contrast, the TEM was low initially (<2mm or r-TEM<1%), and then increased (<4.5mm and 2.5%, TEM and r-TEM respectively). These data show that P-values, ICC and r values hold substantial limits for error description as they do not always flag error well. In contrast, TEM appears to covary with error more saliently and holds the advantage that changes are reported in the units of the original measurement. For these reasons, TEM is recommended in favour to P-values, ICC and r.
Article
Graphic exemplars of cranial sex and ancestry are essential to forensic anthropology for standardizing casework, training analysts, and communicating group trends. To date, graphic exemplars have comprised hand-drawn sketches, or photographs of individual specimens, which risks bias/subjectivity. Here, we performed quantitative analysis of photographic data to generate new photo-realistic and objective exemplars of skull form. Standardized anterior and left lateral photographs of skulls for each sex were analyzed in the computer graphics program Psychomorph for the following groups: South African Blacks, South African Whites, American Blacks, American Whites, and Japanese. The average cranial form was calculated for each photographic view, before the color information for every individual was warped to the average form and combined to produce statistical averages. These mathematically derived exemplars—and their statistical exaggerations or extremes—retain the high-resolution detail of the original photographic dataset, making them the ideal casework and training reference standards.
Article
Aging is an inevitable and complex process that can be described clinically as features of wrinkles, sunspots, uneven skin color, and sagging skin. These cutaneous effects are influenced by both intrinsic and extrinsic factors and often are varied based on ethnic origin given underlying structural and functional differences. The authors sought to provide updated information on facets of aging and how it relates to ethnic variation given innate differences in skin structure and function. Publications describing structural and functional principles of ethnic and aging skin were primarily found through a PubMed literature search and supplemented with a review of textbook chapters. The most common signs of skin aging despite skin type are dark spots, loss of elasticity, loss of volume, and rhytides. Skin of color has many characteristics that make its aging process unique. Those of Asian, Hispanic, and African American descent have distinct facial structures. Differences in the concentration of epidermal melanin makes darkly pigmented persons more vulnerable to dyspigmentation, while a thicker and more compact dermis makes facial lines less noticeable. Ethnic skin comprises a large portion of the world population. Therefore, it is important to understand the unique structural and functional differences among ethnicities to adequately treat the signs of aging.
Article
Estimating age at death is one of the most important aspects of creating a biological profile. Most adult age estimation methods were developed on North American skeletal collections from the early to mid-20th century, and their applicability to modern populations has been questioned. In 2010, Hartnett used a modern skeletal collection from the Maricopia County Forensic Science Centre to revise the Suchey-Brooks pubic symphysis method and the İşcan et al. fourth rib methods. The current study tests Hartnett's revised methods as well as the original Suchey-Brooks and İşcan et al. methods on a modern sample from the William Bass Skeletal Collection (N = 313, mean age = 58.5, range 19–92). Results show that the Suchey-Brooks and İşcan et al. methods assign individuals to the correct phase 70.8% and 57.5% of the time compared with Hartnett's revised methods at 58.1% and 29.7%, respectively, with correctness scores based on one standard deviation of the mean rather than the entire age range. Accuracy and bias scores are significantly improved for Hartnett's revised pubic symphysis method and marginally better for Hartnett's revised fourth rib method, suggesting that the revised mean ages at death of Hartnett's phases better reflect this modern population. Overall, both Hartnett's revised methods are reliable age estimation methods. For the pubic symphysis, there are significant improvements in accuracy and bias scores, especially for older individuals; however, for the fourth rib, the results are comparable to the original İşcan et al. methods, with some improvement for older individuals.
Article
The post-mortem resilience of facial creases was studied using donated bodies in order to establish the efficacy of crease analysis for identification of the dead. Creases were studied on normal (pre-embalmed) and bloated (embalmed) cadavers at the Centre for Anatomy and Human Identification (CAHID) to establish whether facial bloating would affect facial crease visibility. Embalming was chosen to simulate the effects produced by post-mortem bloating. The results suggested that creases are resilient and changes were only detected for creases located on the periphery of the face, particularly at areas where the skin is thick, such as at the cheeks. Two new creases not previously classified were identified; these creases were called the vertical superciliary arch line and the lateral nose crease. This research suggests that facial creases may be resilient enough after death to be utilised for human identification.
Article
The perception and recognition of photographic images of famous faces was compared with the same images transformed to produce caricatures of different degrees of exaggeration. Following Brennan (1982; 1985). caricatures were produced by first comparing the position of facial features in a frame-grabbed image with the average position for a series of faces; deviations from the average were then accentuated by a constant fraction (16, 32 or 48%). Photographic quality caricatures for seven famous faces were generated by distorting regions of the original images in accordance with the change in feature positions. Images reducing the distinctiveness of faces (anticaricatures) were produced by decreasing deviations from the norm. In Experiment 1, perceptual ratings of the degree to which images resembled the individuals depicted was found to vary with the degree of caricaturing (−32, −16, 0, +16, +32%). Interpolation from the data indicated that the best likeness occurred for images with a small degree of positive exaggeration (+4.4% on average). The magnitude of this caricature advantage correlated with the familiarity with the target faces and with the quality of the caricaturing proccss as assessed independently by caricature artists. Experiment 2 examined the recognition of normal and caricatured images in a namdface matching task. Overall, the subjects' fastest reaction times occurred for images with positive caricaturing. The caricature advantage was primarily attributed to improved performance on trials where the name and face did not match. The results suggest that both the precise metric proportions of faces and the way faces deviate from average are represented in memory. The results also indicate that the “super-fidelity” of caricatures found (Modes, Brennan & Carey, 1987) is not restricted to line drawings and may, therefore, have implications for how we recognise natural facial images.SUMMARY OF RESULTSExperiment 1Perceptual ratings of the degree to which images resembled depicted individuals was found to vary with level of caricaturing. Interpolation indicated the best likeness would occur with a small degree of positive caricaturing (+4.4% on average). The magnitude of the caricature advantage at the perceptual level correlated with the familiarity of the faces and with the quality of the caricaturing process as judged by caricature experts.Experiment 2Overall analysis of the degree of image manipulation producing the fastest reaction times for individual subjects revealed a caricature advantage. This increased speed of processing for caricatured images did not reflect any speed-accuracy trade-off. Caricaturing images can therefore produce more efficient processing in a task requiring matching of a person's face and name.In the overall analysis of variance of reaction times (containing match and non-match trials), the caricature advantage did not achieve statistical significance. Three factors might have contributed to the lack of effect. First, the caricature advantage was relatively small in magnitude amounting to a 3% increase in speed. Secondly, the amount of caricaturing producing optimal speed of processing varied across subjects, some performing best with +16% caricatures, others with +32% caricatures. Finally, and of more theoretical interest, the effects of caricaturing appeared to depend on the type of trial. There was no caricature advantage on congruous trials when the name matched the subsequently presented face image. The caricature advantage was prevalent, however, on incongruous trials where the face and name did not match. With non-match trials, + l6% caricatures were processed significantly faster than the veridical images. Again the increase in speed of processing was not an artefact produced by a speed-accuracy trade-off.
Article
Published formulas for the large sample variance of the kappa statistic that are appropriate for the case of different sets of raters for different Ss, when each set of raters is selected at random from a larger pool of available raters, are determined to be incorrect. New formulas are derived and checked by Monte Carlo simulation. Kappa is shown to be identical, except for terms that go to zero as the number of Ss increases, to the intraclass correlation coefficient resulting from applying a one-way ANOVA to the data. (10 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
The objective of this study was to measure: (1) normal sex-related dimensions of external nose (linear distances, ratios, angles, volume and surface area); and (2) growth changes between childhood and old age. The three-dimensional coordinates of several soft-tissue landmarks on the external nose were obtained by a non-invasive, computerized digitizer in 519 male and 340 female healthy subjects aged 4-73 years. The subjects were divided into 11 non-overlapping age groups: for children and preadolescent subjects, 2-year spans were used, while larger intervals were used for adolescent and adult subjects. From the landmarks, nasal volume and external surface area; nasal and alar base widths, nasal height, nasal bridge length, philtrum length, nasal tip protrusion, right and left nostril lengths, superior and inferior nostril widths; nasal tip protrusion-to-nasal height, and nasal width-to-nasal height ratios; nasal convexity, alar slope, and nasal tip angles were calculated, and averaged for age and sex. Comparisons were performed by factorial analysis of variance. On average, men had larger nasal external volume and area, linear distances and nasal width-to-height ratio than women (p<0.01); no sex differences were found for the angles and the nasal tip protrusion-to-nasal height ratio. Age significantly influenced all analyzed measurements (p<0.001): nasal volume, area, linear distances increased from childhood to old age, while the nasal tip angle decreased as a function of age. No consistent age related patterns were found for the ratios and the nasal convexity and alar slope angles. Men and women had different age related patterns, with significant sex by age interactions (p<0.001). Overall, in most occasions male increments in nasal dimensions were larger than female ones. Data collected in the present investigation could serve as a database for the quantitative description of human nasal morphology during normal growth, development and aging. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, aging of living and dead persons, personal identification) may also benefit from age and sex based data banks.
Article
The objective of this study was to supply information about: (1) normal sex-related dimensions of ears (linear distances and ratios, area); (2) left-right symmetry; and (3) growth changes between childhood and old age. The three-dimensional coordinates of several soft-tissue landmarks on the ears and face were obtained by a non-invasive, computerized electromagnetic digitizer in 497 male and 346 female healthy subjects aged 4-73 years. From the landmarks, paired ear width and length, the relevant ratios, ear areas and angles relative to the facial midline, as well as indices of left-right symmetry, were calculated, and averaged for age and sex. Comparisons were performed by factorial analysis of variance. All ear dimensions were significantly larger in men than in women (p<0.001). A significant effect of age was found (p<0.001), with larger values in older individuals. The ear width-to-length ratio and the sagittal angle of the auricle significantly decreased as a function of age (p<0.001) but without sex-related differences. On average, the three-dimensional position of ears was symmetric, with symmetry coefficients ranging between 92% and 96%. Asymmetry was found in the sagittal angle of the auricle (both sexes), in the ear width-to-length ratio and ear width (men only). Data collected in the present investigation could serve as a data base for the quantitative description of human ear morphology and position during normal growth, development and aging. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, aging of living and dead persons, personal identification) may also benefit from age- and sex-based data banks.
Article
The normal growth, development, and aging of facial soft tissues was studied by three-dimensional (3D) computerized mesh diagram analysis. The 3D coordinates of 50 soft-tissue landmarks were collected from 591 healthy white northern Italians (351 males, 240 females) 6-40 years of age. For each gender and age class, mean values were computed, and a standardized mesh of equidistant horizontal, vertical, and anterior-posterior lines was constructed. Within each age group, male meshes were superimposed on female meshes. For each gender, the 6-year-old reference mesh was superimposed on the reference mesh of each age group. The global (size plus shape) difference was evaluated by calculating the relevant displacement vectors for each landmark. Consequently, a size normalization was carried out and the shape difference was evaluated by calculating new relevant displacement vectors for each landmark. Growth and development were different along the three spatial planes: the largest increment was observed in the vertical dimension, with major modifications in the soft-tissue profile. The vertical dimension in males increased even after 30 years of age: ear dimensions increased, trichion moved superiorly and posteriorly, and pogonion, menton, and gonion moved anteriorly and inferiorly. In all age groups, size-standardized shape differences were found in the forehead, lower-third facial profile, eyes, cheeks, and ears. In each age class, male dimensions were larger than female dimensions. During childhood, gender differences in size were limited; shape differences were even less manifest. Overall, the profile was more anterior and inferior, the gonia were more inferior and more lateral, the forehead was more anterior, and the ears were larger in males than in females of corresponding age.
Article
This article describes and tests a photography rig that has been built at the University of Melbourne, Australia, specifically for the purpose of taking rapid and highly standardized craniofacial photographs, in simultaneous views of front and profile. The rig uses a novel projected light range-finding system that has been designed for easy and accurate positioning of subjects, in the natural head position, at precise distances from the frontal camera. Results of experiments examining the intraobserver error of multiple photographs taken on the rig indicate that high-quality, repeatable photographs can be taken after a reasonably large amount of time has lapsed between photography sessions (e.g., 30 days). This study also indicates that some variability remains between photographs even when highly standardized protocols are followed. Consequently, it is expected that the variation between photographs with limited standardization is much larger and more likely to cause significant errors in any comparisons.
Article
This paper is a summary of findings of adult age-related craniofacial morphological changes. Our aims are two-fold: (1) through a review of the literature we address the factors influencing craniofacial aging, and (2) the general ways in which a head and face age in adulthood. We present findings on environmental and innate influences on face aging, facial soft tissue age changes, and bony changes in the craniofacial and dentoalveolar skeleton. We then briefly address the relevance of this information to forensic science research and applications, such as the development of computer facial age-progression and face recognition technologies, and contributions to forensic sketch artistry.
Article
In an age of global combat against terrorism, the recognition and identification of people on document images is of increasing significance. Experiments and calculations have shown that the camera-to-subject distance - not the focal length of the lens - can have a significant effect on facial proportions. Modern passport pictures should be able to function as a reference image for automatic and manual picture comparisons. This requires a defined subject distance. It is completely unclear which subject distance, in the taking of passport photographs, is ideal for the recognition of the actual person. We show here that the camera-to-subject distance that is perceived as ideal is dependent on the face being photographed, even if the distance of 2m was most frequently preferred. So far the problem of the ideal camera-to-subject distance for faces has only been approached through technical calculations. We have, for the first time, answered this question experimentally with a double-blind experiment. Even if there is apparently no ideal camera-to-subject distance valid for every face, 2m can be proposed as ideal for the taking of passport pictures. The first step would actually be the determination of a camera-to-subject distance for the taking of passport pictures within the standards. From an anthropological point of view it would be interesting to find out which facial features allow the preference of a shorter camera-to-subject distance and which allow the preference of a longer camera-to-subject distance.
Two-dimensional computer generated average human face morphology and facial approximation
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C.N. Stephan, I. Penton-Voak, D.I. Perrett, B. Tiddeman, J. Clement, M. Henneberg, Two-dimensional computer generated average human face morphology and facial approximation, in: J. Clement, M. Marks (Eds.), Comput.-Graph. Facial Reconstr., Academic Press, Boston, 2005, pp. 105-127.
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New assault on academic excellence -research grants cut amid funding shortage, Dly. Maverick
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B. Bozzoli, New assault on academic excellence -research grants cut amid funding shortage, Dly. Maverick. (2017). https://www.dailymaverick.co.za/article/2017-10-08-op-ed-new-assaulton-academic-excellence-research-grants-cut-amid-funding-shortage/#.WrzHPIiuzIV (accessed March 29, 2018).
Lack of Resources is Crippling Effective Policing Study Finds
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S. Mabena, Lack of Resources is Crippling Effective Policing Study Finds, Bus. Day, 2017. https://www.businesslive.co.za/bd/national/2017-03-23-lack-ofresources-is-crippling-effective-policing-study-finds/. (Accessed 29 March 2018).
Mid-year Population Estimates
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P. Lehohla, Mid-year Population Estimates, Statistics South Africa, South Africa, 2016. http://www.statssa.gov.za/. (Accessed 25 March 2018).
Frankfurt Horizontal Plane
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Mosby, Frankfurt Horizontal Plane, Mosbys Med Dict., 2016, pp. 724.
A morphological and biometric study of the facial characteristics of two South African childhood populations at different age levels, Doctoral thesis
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N. Briers, A morphological and biometric study of the facial characteristics of two South African childhood populations at different age levels, Doctoral thesis, University of Pretoria, 2015.
Computer graphics in facial perception research
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Neyman-Pear son or NHST? A tutorial for teaching data testing
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J.D. Perezgonzalez, Fisher, Neyman-Pear son or NHST? A tutorial for teaching data testing, Front. Psychol. 6 (2015) 1-11. doi:10.3389/fpsyg.2015.00223.
Is South Africa a Third World country?, Free Mark
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A Morphological and Biometric Study of the Facial Characteristics of Two South African Childhood Populations at Different Age Levels
  • N Briers
N. Briers, A Morphological and Biometric Study of the Facial Characteristics of Two South African Childhood Populations at Different Age Levels, Doctoral Thesis, University of Pretoria, 2015.