The investigation of the changing facial appearance of identical twins employing a three-dimensional laser imaging system

OBJECTIVE: An investigation to determine the changing facial appearance of identical twins. DESIGN: Clinical study. MATERIALS AND METHODS: Two Minolta Vivid 900 3D optical laser scanners were placed as a stereo pair to capture the soft tissues of a pair of identical twins. Each scan took approximately 2.5 s. The scanned whole faces were superimposed to determine changes in facial morphologies at different time intervals. OUTCOME MEASURES: The shell deviations between left and right scans of each patient were recorded and analysed for differences. Furthermore, final merged faces were overlaid to determine the changes in facial morphology over time. RESULTS: The results showed that changes in height and weight correlated with changes in facial morphology. CONCLUSION: The 3D laser scanning device is a clinically useful tool in the study of facial growth and facial morphology in a pair of twins.     

Foetal alcohol syndrome: a cephalometric analysis of patients and controls

Foetal alcohol syndrome (FAS) consists of multi-system abnormalities and is caused by the excessive intake of alcohol during pregnancy. The teratogenic effect of alcohol on the human foetus has now been established beyond reasonable doubt and FAS is the most important human teratogenic condition known today. The purpose of this study was to analyse the craniofacial parameters of children with FAS and compare them with matched controls. Ninety children diagnosed with FAS (45 males, 45 females) and 90 controls were matched for age, gender, and social class. The mean age of the FAS children was 8.9 years with the controls slightly older at 9.1 years. This age difference was not significant (P = 0.34). A standard lateral cephalometric radiograph of each subject was taken. The radiographs were digitized for 20 linear and 17 angular measurements. These 37 variables were formulated to assess the size, shape, and relative position of three craniofacial complexes: (1) the cranial base, (2) midface, and (3) mandible. In addition, nine variables were computed to compare the soft tissue profiles. The study showed that measurements related to face height and mandibular size appear to be the most important features when distinguishing FAS children. Overall, the FAS children in the present study presented with vertically and horizontally underdeveloped maxillae, together with features of long face syndrome with large gonial angles and a short ramus in relation to total face height. There was also a tendency for the development of an anterior open bite, which appears to be compensated for by an increase in the vertical dimension of the anterior alveolar process to bring the incisor teeth into occlusion. The latter adaptation occurred mainly in the mandible.     

A three-dimensional look for facial differences between males and females in a British-Caucasian sample aged 151/2 years old

BACKGROUND: Optical surface scanning accurately records the three-dimension (3D) shape of the face non-invasively. Many software programs have been developed to process and analyze the 3D data, enabling the clinicians to create average templates for groups of subjects to provide a comparison of facial shape. OBJECTIVE: Differences in facial morphology of males and females were identified using a laser scan imaging technology. SUBJECTS AND METHODS: This study was undertaken on 380 British-Caucasian children aged 15 and a half year old, recruited from the Avon Longitudinal Study of Parents and Children (ALSPAC). 3D facial images were obtained for each individual using two high resolution Konica/Minolta laser scanners. The scan quality was assessed and any unsuitable scans were excluded from the study. Average facial templates were created for males and females, and a registration technique was used to superimpose the facial shells of males and females so that facial differences can be quantified. RESULTS: Thirty unsuitable scans were excluded from the study. The final sample consisted of 350 subjects (166 females, 184 males). Females tend to have more prominent eyes and cheeks in relation to males with a maximum difference of 2.4 mm. Males tend to have more prominent noses and mouths with a maximum difference of 2.7 mm. About 31% of the facial shells match exactly (no difference), mainly in the forehead and chin regions of the face. CONCLUSIONS: Differences in facial morphology can be accurately quantified and visualized using 3D imaging technology. This method of facial assessment can be recommended and applied for future research studies to assess facial soft tissue changes because of growth or healthcare intervention.     

A cephalometric assessment of children with fetal alcohol syndrome

Lateral cephalometric radiographs were quantitatively assessed in a series of 15 American black children with fetal alcohol syndrome (FAS). Although none was profoundly affected, FAS had been diagnosed in all the children at birth. Comparisons with age-, sex-, and race-matched controls disclosed a triad of facial profile differences: (1) frontal bossing, (2) palatal plane tipped up in the front with proclined upper incisors and a sharp nasolabial angle acquired from digit habits, and (3) above-average length of the mandibular corpus. Collectively these generate the perception of midface hypoplasia, although the midface actually is unremarkable in size and position. A high prevalence of chronic digit habits (8 of 15) is a secondary consideration in FAS, leading to localized skeletodental problems.     

Three-dimensional facial characteristics of Caucasian infants without cleft and correlation with body measurements.

OBJECTIVE: The aim of this study was to characterize the soft tissue facial features of infants without cleft and to report on the correlation between these with weight, length, and head circumference. DESIGN: This was a prospective study using a noninvasive three-dimensional (3D) stereophotogrammetry (C3D) system to capture the images of the participants. Landmarks were identified on the 3D facial images. Means and SDs were derived for facial distances and angles. A facial asymmetry score was calculated for each image. Two sample Student's t tests, Pearson's correlation coefficients and analysis of covariance were used to ascertain any gender differences and determine whether these could be explained by weight differences. PARTICIPANTS: Eighty-three infants, 41 boys and 42 girls, were captured at rest with their lips apart, at approximately 3 months of age. RESULTS: Significant sex differences, of 1 to 2 mm, were found in several facial dimensions, such as face height and nose width. The larger facial measurements correlated significantly with body measurements. Analysis of variance confirmed these differences could be explained by differences in weight. There were no sex differences in the nose/mouth width ratios or in any of the angles measured, suggesting that there may be little sex difference in shape. A slight degree of asymmetry in the faces of infants without cleft was detected. CONCLUSIONS: Comparisons between noncleft controls and infants with cleft should take cognizance of normal age and sex variations in height and weight that occur among infants.     

Face shape of unaffected parents with cleft affected offspring: combining three‐dimensional surface imaging and geometric morphometrics

Authors – Weinberg SM, Naidoo SD, Bardi KM, Brandon CA, Neiswanger K, Resick JM, Martin RA, Marazita ML Objective – Various lines of evidence suggest that face shape may be a predisposing factor for non‐syndromic cleft lip with or without cleft palate (CL/P). In the present study, 3D surface imaging and statistical shape analysis were used to evaluate face shape differences between the unaffected (non‐cleft) parents of individuals with CL / P and unrelated controls. Methods – Sixteen facial landmarks were collected from 3D captures of 80 unaffected parents and 80 matched controls. Prior to analysis, each unaffected parent was assigned to a subgroup on the basis of prior family history (positive or negative). A geometric morphometric approach was utilized to scale and superimpose the landmark coordinate data (Procrustes analysis), test for omnibus group differences in face shape, and uncover specific modes of shape variation capable of discriminating unaffected parents from controls. Results – Significant disparity in face shape was observed between unaffected parents and controls (p < 0.01). Notably, these changes were specific to parents with a positive family history of CL / P. Shape changes associated with CL / P predisposition included marked flattening of the facial profile (midface retrusion), reduced upper facial height, increased lower facial height, and excess interorbital width. Additionally, a sex‐specific pattern of parent‐control difference was evident in the transverse dimensions of the nasolabial complex. Conclusions – The faces of unaffected parents from multiplex cleft families displayed meaningful shape differences compared with the general population. Quantitative assessment of the facial phenotype in cleft families may enhance efforts to discover the root causes of CL /P.     

Foetal alcohol syndrome: a dental and skeletal age analysis of patients and controls

Foetal alcohol syndrome (FAS) consists of multisystem abnormalities and is caused by the excessive intake of alcohol during pregnancy. The teratogenic effect of alcohol on the human foetus has now been established beyond reasonable doubt and FAS is one of the most important human teratogenic conditions known today. The purpose of this study was to assess the dental age (DA) and skeletal age (SA) of children with FAS and compare them with matched controls. The samples of 90 children diagnosed with FAS and 90 controls were matched for age, gender, and social class. The mean chronological age (CA) of the FAS subjects was 8.95 years, with the controls slightly older at 9.04 years. This difference was not significant. Dental maturity was determined by assessing the stage of tooth formation and SA assessment was made from hand-wrist radiographs for the patients and controls by assigning a SA and comparing it with standard plates. The means and standard deviations of CA and DA for the stages of calcification were calculated and the Pearson ranked order correlation coefficient was applied to measure the associations between skeletal maturity indicators and DA. t-tests were used to test for group differences between independent groups, and paired t-tests to determine paired group differences. This study provided evidence of a positive association between DA and SA in both the FAS children and the controls. The data suggest that both DA and SA may be a reflection of general somatic growth. It must be acknowledged that growth of individuals is often irregular, when any norms of development based on central tendencies and variabilities of healthy children are applied. Some aspects of growth and development for healthy children may show a variable pattern of growth. Therefore, correlation of these aspects of growth and development will often not show the degree of correlation that theoretically exists between different areas of growth and development. A more complete appraisal of the entire skeleton and an evaluation of the entire dentition, rather than just the mandibular teeth, might improve the correlation between the variables.     

Facial characterization of infants with cleft lip and palate using a three-dimensional capture technique.

OBJECTIVE: To characterize the soft tissue features of infants with unilateral cleft lip (UCL) and unilateral complete cleft lip and palate (UCLP) prior to primary surgery and compare with noncleft controls. DESIGN: Prospective controlled capture of the facial morphology of infants using a noninvasive three-dimensional stereophotogrammetry method. PARTICIPANTS: 23 children with presurgical cleft: 11 UCL (M = 6, F = 5); 12 UCLP (M = 9, F = 3), and 21 noncleft controls (M = 7, F = 14) were imaged at approximately 3 months of age (range 10 to 16 weeks). MAIN OUTCOME MEASURE: Accurate, repeatable quantification of facial soft tissues in infants with clefts prior to surgery. RESULTS: Significant differences (p <.05) were found between the UCLP group and UCL and control groups in anatomical and soft nose width, cleft-side alar wing length, and nasal tip horizontal displacement. Both cleft groups were significantly different from controls and from each other in cleft-side nostril dimensions, alar wing angulation, columella angle, and alar base to corner of mouth dimension; alar base width; and soft tissue defect in nose and the lip and philtrum length bordering the cleft. Significant differences between clefts and controls were identified in the nostril and philtrum on the noncleft side. CONCLUSIONS: The use of children with UCL as controls for UCLP studies is inappropriate. This technique overcame the limitations of direct measurement of infant faces to aid the surgeon in the planning and subsequent re-evaluation of surgical rationale.     

Fetal alcohol syndrome and developing craniofacial and dental structures--a review

OBJECTIVES: Fetal alcohol syndrome (FAS) is a collection of signs and symptoms seen in children exposed to alcohol in the prenatal period. It is characterized mainly by a distinct pattern of craniofacial malformations, physical and mental retardation. However, with the increased incidence of FAS, there is a great variation in the clinical features of FAS. DESIGN: Narrative review. RESULTS: This review describes data from clinical and experimental studies, and in vitro models. Experimental studies have shown that alcohol has a direct toxic effect on the ectodermal and mesodermal cells of the developing embryo, particularly in the cells destined to give rise to dentofacial structures (i.e. cranial neural crest cells). Other effects, such as, abnormal pattern of cranial and mandibular growth and altered odontogenesis are described in detail. The exact mechanism by which alcohol induces its teratogenic effects remains still unknown. The possible mechanisms are outlined here, with an emphasis on the developing face and tooth. Possible future research directions and treatment strategies are also discussed. CONCLUSION: Early identification of children affected by prenatal alcohol exposure leads to interventions, services, and improved outcomes. FAS can be prevented with the elimination of alcohol consumption during pregnancy. We need to provide education, target high-risk groups, and make this issue a high priority in terms of public health.     

The perception of facial asymmetry using 3-dimensional simulated images

Objective:To investigate the perception of facial asymmetry in young adults to identify the amounts of chin asymmetry that can be regarded as normal and may benefit from correction.Materials and Methods:Three-dimensional (3D) images of 56 individuals of mixed ethnicity were obtained and used to produce average 3D images of male and female faces. Distortion was then applied to these average faces using a 3D graphics package to simulate different amounts of chin point asymmetry. Five observer groups (lay individuals, dental students, dental care professionals, dental practitioners, and orthodontists) assessed timed presentations of 3D images, rating them as “normal,” “acceptable,” or “would benefit from correction.” Time-to-event analysis was used to assess the level of chin asymmetry perceived as normal and beneficial for correction for each group.Results:The factors influencing the perception of facial asymmetry were the degree of asymmetry and the observer group. Direction of the asymmetry and gender of the assessed individual did not affect the perception of asymmetry, except in the 4- to 6-mm distortion range. The gender of the observer had no influence on perception. There were statistically significant differences in the amounts of asymmetry that the laypeople and orthodontists considered to be normal (5.6 ± 2.7 mm and 3.6 ± 1.5 mm, respectively; P < .001) and felt would benefit from surgical correction (11.8 ± 4.0 mm and 9.7 ± 3.0 mm, respectively; P  =  .001).Conclusions:Perception of asymmetry is affected by the amount of asymmetry and the observer group, with orthodontists being more critical.     

Soft tissue facial angles in individuals with ectodermal dysplasia: A three-dimensional noninvasive study.

OBJECTIVE: To supply quantitative information about the facial soft tissues of patients with hypohidrotic ectodermal dysplasia. DESIGN: Prospective assessment. SETTING: National meetings of hypohidrotic ectodermal dysplasia patients and families. PATIENTS AND MAIN OUTCOME MEASURES: Facial and mandibular corpus convexities in the horizontal plane; facial convexity in the sagittal plane; interlabial, naso-labial, nasal convexity, and left and right soft tissue gonial angles were calculated from the three-dimensional coordinates of 11 soft tissue facial landmarks obtained in 18 male and 17 female hypohidrotic ectodermal dysplasia patients aged 3 to 41 years and in 504 reference healthy individuals. In addition, z-scores were computed and the patients were grouped by cluster analysis. RESULTS: Male and female z-scores did not differ. In the pooled group, facial convexities in the horizontal and sagittal planes were significantly (Student's t, p < .01) increased (flatter) in hypohidrotic ectodermal dysplasia patients, compared with normal controls. The naso-labial angle was significantly reduced (more acute). Upper and lower facial convexity and mandibular corpus convexity in the horizontal plane deviated less from the norm with increasing age. Facial convexity in the horizontal and sagittal planes, soft tissue gonial angles, and naso-labial and interlabial angles deviated less from the norm with increasing number of teeth present in the mouth. Cluster analysis identified three homogeneous groups, all characterized by a peculiar facial phenotype. Modifications in facial convexity and gonial and interlabial angles differentiated each cluster. CONCLUSIONS: Patients with hypohidrotic ectodermal dysplasia had flatter faces in the horizontal and sagittal planes than normal controls had. Cluster analysis revealed patterned differences in facial phenotype.     

新疆喀什地区维吾尔族青年面部三维扫描的形态学研究

目的:利用三维扫描技术获取新疆喀什地区维吾尔族青年人群颌面部二维及三维数据,比较维吾尔族男性与女性面部差异性。方法:采用3DCaMega光学三维扫描仪收集341例维吾尔族样本,男性116例,女性225例,应用Geomagic studio软件对数据进行重建、定点、测量、验证测量值可重复性、测量标志点间的平面距离及曲面距离,应用SPSS24.0软件进行统计学分析。结果:9个测量指标重复性好(P>0.05),比较维吾尔族男性及女性面部距离参数,其中两眼间距、外眦间距、鼻长、面下1/3高度,平面与曲面测量值男女间均存在显著差异(P<0.05);额高、鼻宽平面测量值无统计学意义(P>0.05),曲面测量值有统计学差异(P<0.05)。结论:三维面部测量的方法在反映面部复杂结构的差异性方面更加精确,是一个有价值、可靠人体测量学工具。     

Perceptions of facial aesthetics in two and three dimensions

The aims of this study were to investigate whether the preferred facial relationship chosen by professionals and the general public is Class I and to ascertain whether viewing two-dimensional (2D) or three-dimensional (3D) images had any effect on the ranking of facial attractiveness. Orthodontists (n = 47), maxillofacial surgeons (n = 25) and members of the general public (n = 78) assessed 2D and 3D facial scans of two males and two females that had been morphed to produce five images reflecting different skeletal patterns: Class I, mild and moderate Class II, and mild and moderate Class III. Each assessor placed the images in rank order of preference, after viewing alternate 2D and 3D image formats for each face. The data were analysed using logistic regression.In 2D, professionals (orthodontists and maxillofacial surgeons) chose Class I as the preferred facial image more frequently than the general public for only one of the four faces. However, in 3D format they chose Class I as the preferred facial image for some subject faces more, and others less, frequently when compared with the general public. The gender of the assessor was not significant when assessing the preferred facial relationship for Class I images in either 2D or 3D formats. The oldest assessors (56+ years) were significantly less likely than the younger age groups to select Class I as the preferred facial relationship in both 2D and 3D. In summary, there was too great a degree of variation to say that a difference between 2D and 3D facial images was evident.     

A new method for the 3D measurement of postoperative swelling following orthognathic surgery

OBJECTIVE: To describe a new method for measuring facial swelling following orthognathic surgery using a 3D laser-scanning device. DESIGN: Prospective clinical trial. Setting and Sample Population -- University Dental Hospital, Wales College of Medicine, Biology Life and Health Sciences. Three subjects requiring bi-maxillary orthognathic surgery were recruited for the study. EXPERIMENTAL VARIABLES: Laser-scanned images of the subjects were obtained under a reproducible and controlled environment with two Minolta Vivid 900 (Osaka, Japan) optical laser-scanning devices assembled as a stereo-pair. A set of left and right scanned images was taken for each subject and each scan took an average of 2.5 s. 3D laser scans were recorded over six time periods (T1 -- pre-surgical scan, postoperatively: T2 -- 1 day, T3 -- 1 week, T4 -- 1 month, T5 -- 3 months and T6 -- 6 months). OUTCOME MEASURE: Facial scans from different time periods were overlaid onto the baseline (T6) facial scan to determine the reduction and changes in swelling following orthognathic surgery. RESULTS: The results showed that swelling could be accurately quantified following surgery. Furthermore, there was a significant reduction in the amount of swelling 1 month postoperatively. Furthermore, the facial morphology returned to approximately 90% of the baseline facial scan at 3 months. CONCLUSION: The 3D laser-scanning device and the method described was a reliable and accurate measure of facial swelling following surgery.     

A new method for automatic tracking of facial landmarks in 3D motion captured images (4D)

The aim of this study was to validate the automatic tracking of facial landmarks in 3D image sequences. 32 subjects (16 males and 16 females) aged 18–35 years were recruited. 23 anthropometric landmarks were marked on the face of each subject with non-permanent ink using a 0.5 mm pen. The subjects were asked to perform three facial animations (maximal smile, lip purse and cheek puff) from rest position. Each animation was captured by the 3D imaging system. A single operator manually digitised the landmarks on the 3D facial models and their locations were compared with those of the automatically tracked ones. To investigate the accuracy of manual digitisation, the operator re-digitised the same set of 3D images of 10 subjects (5 male and 5 female) at 1 month interval. The discrepancies in x, y and z coordinates between the 3D position of the manual digitised landmarks and that of the automatic tracked facial landmarks were within 0.17 mm. The mean distance between the manually digitised and the automatically tracked landmarks using the tracking software was within 0.55 mm. The automatic tracking of facial landmarks demonstrated satisfactory accuracy which would facilitate the analysis of the dynamic motion during facial animations.     

Fetal alcohol syndrome: anthropometric and oral health status

The purpose of this study was to analyze the anthropometric measures and oral health status of children with fetal alcohol syndrome (FAS) and compare them to matched controls. The sample of 90 cases (children diagnosed with FAS) and 90 controls were matched for age, gender, and social class. The mean age of the cases was 8.9 years with the controls slightly older at 9.1 years. The results of the anthropometric measurements in respect of weight, height, and head circumference showed significantly lower values for the FAS children when compared to the controls. Several physical abnormalities described in children with FAS were seen in this study. Some of these abnormalities seen in the FAS children included deformities in the small joints of the hand, altered palmar creases, and malformation of the ears. The prevalence of enamel opacities between FAS and controls was not significantly different and averaged around 15% for both groups. More than three quarters of both the cases and the controls demonstrated the presence of plaque and almost two-thirds demonstrated gingival bleeding on probing. FAS patients had statistically significantly (p<0.001) more dentofacial anomalies than the controls. The mean decayed, missing, and filled teeth (dmft) score for the FAS sample was slightly higher, though not significantly different from that of the controls, and the decayed component (d) made up the largest part of the index in both groups.     

2D and 3D analysis methods of facial asymmetry in comparison

Symmetry is a significant factor, among others, influencing the attractiveness of human faces. Hence its restoration is an essential task in oral and maxillofacial surgery. Until recently, most of the techniques to objectively quantify the facial asymmetry were based on the evaluation of two-dimensional data, i.e. photographs. These techniques are well-established in literature and have in common that several landmarks in the face are identified manually and put together in a formula to obtain a facial asymmetry value. The increasing availability of three-dimensional measuring systems offers the possibility to perform an automated 3D analysis of the facial symmetry based on a dense 3D point cloud of the facial surface. The results of this analysis are on the one hand a mirror plane, which meets best the partial symmetry of the face regarding the median sagittal plane, and on the other hand a 3D asymmetry index quantifying the overall facial asymmetry characteristics. In this paper three selected 2D analysis methods and one 3D analysis method are compared.     

Fluctuating asymmetry of dynamic smiles in normal individuals

The aim of this study was to quantify the fluctuating dynamic facial asymmetry during smiling in a group of ‘normal’ adults, using three-dimensional (3D) motion facial capture technology. Fifty-four male and 54 female volunteers were recruited. Each subject was imaged using a passive markerless 3D motion capture system (DI4D). Eighteen landmarks were tracked through the 3D capture sequence. A facial asymmetry score was calculated based on either a clinically derived midline or Procrustes alignment; scores were based on the Euclidean distance between landmark pairs. Facial asymmetry scores were determined at three time points: rest, median, and maximum frame. Based on the clinically derived midline and on Procrustes alignment, the differences between male and female volunteers, as well as those at the three different time points, were not clinically significant. However, throughout a smile, facial and lip asymmetry scores increased over the duration of the smile. Fluctuating facial asymmetry exists within individuals, as well as between individuals. Procrustes superimposition and the clinically derived midline produced similar asymmetry scores and both are valid for symmetrical faces. However, with facial asymmetry, Procrustes superimposition may not be a valid measure, and the use of the clinically derived midline may be more appropriate, although this requires further investigation.     

Reproducibility of facial soft tissue landmarks on 3D laser‐scanned facial images

Authors – Toma AM, Zhurov A, Playle R, Ong E, Richmond S Background – The three‐dimensional (3D) measuring technology is useful to inspect facial shape in three planes of space (X, Y, and Z). Recent work has been directed to analyse craniofacial morphology using facial soft tissue landmarks to identify facial differences among population. The reproducibility of facial landmarks is almost necessary to ensure accurate 3D facial measurements. Objective – The aim of this study is to assess the reproducibility of facial soft tissue landmarks using laser‐scan 3D imaging technology. Subjects and Methods – Facial landmarks were assessed for 30 15½‐year‐old British‐Caucasian children (15 males and 15 females). The sample was recruited from the Avon Longitudinal Study of Parents and Children (ALSPAC). The 3D facial images were acquired for each subject using two high‐resolution Konica/Minolta laser scanners. Twenty‐one facial landmarks (63 X, Y, and Z coordinates) were identified and recorded on each 3D facial image by two examiners. The reproducibility of landmarks identification at 2‐week interval was assessed for one of the examiners (intra‐examiner). In addition, the reproducibility of landmarks was assessed between the two examiners (inter‐examiner). Using Bland‐Altman plots, both intra‐ and inter‐examiner assessments had evaluated landmarks reproducibility in three dimensions for the sample divided by gender. The reproducibility of the 3D‐coordinates for each landmark was considered under three categories (< 0.5 mm, < 1 mm, and >1 mm) for both intra‐ and inter‐examiner reproducibility assessments. Results – The distribution of coordinates at the three levels of reproducibility show the following percentages: intra‐examiner: < 0.5 mm (38%), < 1 mm (51%), >1 mm (11%); inter‐examiner: < 0.5 mm (35%), < 1 mm (48%), >1 mm (17%). Generally, 10 landmarks were reproducible to less than 1 mm for both intra‐ and inter‐examiner reproducibility assessments. The Labiale Superius was the most reproducible and Palebrale Superius was the least reproducible landmark. Some landmarks showed greater reliability in certain planes of space; the Glabella was more reliable in the Z than the Y axis. Gender differences were found; Subnasale was more reproducible in the Y‐axis in males compared with females. Conclusions – The reproducibility of facial landmarks should be considered in the three planes of space. The majority of X‐Y‐Z coordinates taken to the 21 facial landmarks were reproducible to < 1 mm which is clinically acceptable. The accuracy of landmarks identification ranged from 0.39 to 1.49 mm. The reliability in identification depends on the clarity and definition of each landmark as well as gender characteristics. The different landmarks reproducibility should be considered when evaluating changes related to growth and healthcare interventions.