Craniofacial structures' development in prenatal period: An MRI study.

INTRODUCTION: The development of skeletal structures (cranial base, upper and lower) and upper airways spaces (oropharyngeal and nasopharyngeal) of the skull has always been an issue of great interest in orthodontics. Foetal MRI images obtained as screening exam during pregnancy can help to understand the development of these structures using a sample cephalometric analysis. MATERIAL AND METHODS: A total of 28 MRI images in sagittal section of foetuses from 20th to 32th weeks of gestation were obtained to dispel doubts about the presence of skeletal malformations. Cephalometric measurements were performed on MRI T2-dependent images acquired with a 1.5 T scanner. The Software Osirix 5 permits to study sagittal and vertical dimensions of the skull analysing linear measurements, angles and areas of the skeletal structures. RESULTS: Vertical and sagittal dimension of cranial base, maxilla and mandible grow significantly (P < .01) between the second and third trimester of gestational period as well as nasopharyngeal and oropharyngeal spaces (P < .05). High correlation between the development of anterior cranial base and functional areas devoted to speech and swallow is demonstrated (r: .97). CONCLUSIONS: The development of craniofacial structures during foetal period seems to show a close correlation between skeletal features and functional spaces with a peak between the second and third trimester of gestation. MRI images result helpful for the clinician to detect with a sample cephalometric analysis anomalies of skeletal and functional structures during prenatal period.

Assessing the effects of biomechanical overload on dairy parlor workers' wrist: Definition of a study approach and preliminary results.

BACKGROUND: Dairy milking is a demanding work task that has been associated with hand and wrist musculoskeletal disorders. Clinical approaches to identify the early effects of musculoskeletal disorders among dairy parlor workers' wrist have not been well defined. OBJECTIVES: The purpose of this pilot study was to develop a study protocol that would assist in the identification and quantification of hand and wrist disorders among dairy workers that perform tasks in the dairy parlor. Additionally, such a study protocol was needed to perform relatively rapid assessments of the wrist/hand on large samples of dairy workers. METHODS: Fourteen dairy parlor workers were assessed for i) upper limb symptoms and work history through questionnaire, ii) a physical examination of the upper limb and in particular wrists and iii) wrist ultrasonography. An additional 21 unexposed paired participants (the control group) also participated in the data collection. RESULTS: The study results identified two ultrasound acoustic windows characterized by the highest predictive value for alteration of the wrist's structure. Study results indicated an impairment of the distal median nerve in structure and mobility and impairment of the distal tendon of the muscle extensor carpi ulnaris that included dislocation and frank damage. CONCLUSIONS: This study identified at least two acoustic windows that should be assessed with ultrasound studies on larger groups and in prospective periodical health surveillance of dairy workers. The study confirmed the wrist was at risk for biomechanical stress among workers conducting milking tasks in the dairy parlors.

Automatic detection of neurons in large cortical slices.

The analysis of neuron distribution inside the cerebral cortex is getting more and more attention. It allows assessing, for instance, age-related and pathological decay and preferential connections; moreover, it complements well studies on functional morphology aimed to discovering information coding in neuron assemblies. A large obstacle to these studies is the huge amount of time required by an operator to manually mark the single neurons. We present here an innovative solution for automaticize the entire process: starting from a set of tile images of a given cortical slice, the system stitches all the tiles together, identifies the grey areas and cover them with a mesh. Neurons are automatically identified and their local distribution determined. Key element of the method is a reliable neuron identification algorithm based on a novel multilayer shape analysis of the blobs identified in the tiles images. This allows identifying on average 87+/-6% of the total neurons in the slice, with a false positive ratio of 14+/-9%, in a relatively short processing time. The algorithm was tested on Nissl-stained cortical slices of the BA4 Human area, 10 microm thick, acquired as a meander of tiles ( approximately 3000 images for a slice of medium size) at 40 x magnification, which gives a resolution of 0.264 microm/pixel. Preliminary results on cortical lamination of Human BA4 area are reported. This method is the first automated algorithm for the analysis of a large high-resolution cortical slice.

Single tooth bite forces in healthy young adults.

The assessment of bite forces on healthy single tooth appears essential for a correct quantification of the actual impact of single implant oral rehabilitations. In the present study, a new single tooth strain-gauge bite transducer was used in 52 healthy young adults (36 men, 16 women) with a complete permanent dentition. The influences of tooth position along the dental arch, of side, and of sex, on maximum bite force were assessed by an ANOVA. No significant left-right differences were found. On average, in both sexes the lowest bite force was recorded on the incisors (40-48% of maximum single tooth bite force), the largest force was recorded on the first molar. Bite forces were larger in men than in women (P < 0.002), and increased monotonically along the arch until the first or second permanent molar (P < 0.0001). The present data can be used as reference values for the comparison of dental forces in patients.

Comparison of unilateral chewing movements vs. dental guidance through the dental guidance ratio.

STATEMENT OF PROBLEM: Limited knowledge exists about the interaction between dental morphology and mandibular excursive movements. PURPOSE: This study evaluated dental guidance in lateral excursive movement and its relationship to jaw motion in unilateral chewing. MATERIAL AND METHODS: Three-dimensional mandibular movement paths (in lateral guiding movements and in the final part of a monolateral chewing stroke) were collected with automated infrared motion analysis in 22 subjects with complete, permanent dentitions. On 2 traces selected from the recorded movements, the angular values projected in all planes of space obtained from 2 lines tangent to a point at a distance of 2.5 mm from maximum intercuspation were used to calculate a canine and a molar dental guidance ratio (DGR). Descriptive statistics were computed for the DGRs in the 3 spatial planes. RESULTS: Assuming masticatory movements of any given subject are restricted or guided by dental anatomy, a value below 100% of the DGR was expected. This was true for the frontal plane only, with mean values of approximately 80% (working-side movements, canines, and molars) and approximately 60% (nonworking-side movements for both molars and canines). In the horizontal and sagittal planes, mean values between 102% and 137% were found. CONCLUSION: Within the limitations of this study, masticatory movement was within the physical borders dictated by dental anatomy in the frontal plane only.

The influence of different jaw positions on the endurance and electromyographic pattern of the biceps brachii muscle in young adults with different occlusal characteristics.

To investigate the hypothesis of a functional coupling between the stomatognathic motor apparatus and the muscles of other body districts, as well as between occlusal conditions and neuromuscular performance, two groups of men (age range 20-26 years), with either normal occlusion (14 men) or malocclusion (15 men), sustained with their dominant arm a dumbbell weighing 80% of their maximum while maintaining different jaw positions: mouth open, without dental contact; mouth close, with light dental contact; maximum voluntary clench; maximum voluntary clench on two cotton rolls positioned on the posterior mandibular teeth; maximum voluntary clench on one cotton roll positioned on the right/left-side posterior mandibular teeth. Surface electromyography (EMG) of the biceps brachii muscle was performed, and the endurance time, mean root mean square (rms) potential, and mean median power frequency were computed. The mean potential and median power frequency were also computed for 2-s windows, and values as a function of time were interpolated by a linear regression analysis. Data were compared between groups and trials by using a factorial analysis of variance. The malocclusion group subjects could perform the exercise for a longer time span than the normal occlusion individuals (P < 0.005). During this endurance time their biceps brachii muscles contracted with different patterns: on average, in the malocclusion group they had a larger EMG amplitude (P < 0.005), and a shift of the power spectrum toward lower frequencies (P < 0.005). The factor 'jaw position' was significant only for the endurance time (P < 0.005). In both groups, the longest endurance time was found in the 'clench' trial, while the shortest in the 'right-side bite' trial. In conclusion, a morphologically altered occlusion does not always worsen the muscular performance of other body districts, and the use of occlusal supports (cotton rolls) is not always beneficial.

Repeatability of choku-tsuki and oi-tsuki in shotokan karate: a 3-dimensional analysis with thirteen black-belt karateka.

13 black-belt karateka performed two different standardized counter-offensive techniques. The trajectories of selected body landmarks were studied by using a computerized image analyzer that allows a 3-dimensional reconstruction of standardized movements. The repeatability of both karate techniques was quantified for each participant. Analysis confirmed that more experienced karateka obtained the best repeatability, as already demonstrated in a preliminary study conducted with a smaller sample of less experienced participants.

Three-dimensional inclination of the dental axes in healthy permanent dentitions--A cross-sectional study in a normal population.

The 3-dimensional (3-D) inclination of the facial axis of the clinical crown (FACC) and the size of the clinical crowns were measured in 100 white northern Italians. The subjects consisted of 22 girls and 21 boys, ages 13-15 years (adolescents), and 31 women and 26 men, ages 16-26 years (adults), all with a complete permanent dentition and Class I dental relationships. The 3-D coordinates of dental landmarks were obtained with a computerized electromagnetic digitizer. Clinical crowns heights and FACC inclinations in the anatomical frontal and sagittal planes relative to 2 reference planes, maxillary and mandibular (between the incisive papilla and the intersection of the palatal/lingual sulci of the first permanent molars with the gingival margin), were calculated. Ages and sexes were compared by ANOVA. On average, the frontal plane FACCs of most teeth converged toward the midline plane of symmetry. In contrast, the incisors diverged from the midline plane or were nearly vertical. Within each quadrant, the inclinations of the postincisor teeth progressively increased. In the sagittal plane, most teeth had a nearly vertical FACC. FACC inclinations showed sex- and age-related differences (P < .05). In the frontal plane, the canines, premolars, and molars were more inclined in adolescents than in adults. In the sagittal plane, a large within-group variability was observed. Clinical crown height was significantly larger in males than in females in all maxillary and mandibular canines, premolars, second molars, maxillary central incisors, and first molars. With age, some degree of dental eruption was found in maxillary and mandibular canines, maxillary second premolars, and molars. The age-related decrease in FACC inclination may be the effect of a progressive buccal and mesial drift.

Morphometry of the orbital region: a soft-tissue study from adolescence to mid-adulthood.

The objective of this study was to gain information about normal sex-related linear and angular dimensions of the orbital region; left-right symmetry; and growth changes between adolescence and mid-adulthood. The three-dimensional coordinates of several soft-tissue landmarks on the orbits and face were obtained by an electromagnetic digitizer in 40 male and 33 female adolescents aged 12 to 15 years, 73 female and 89 male young adults aged 19 to 30 years, and 41 male and 38 female adults aged 31 to 56 years. From the landmarks-binocular and intercanthal widths; paired height and inclination of the orbit relative to both the true horizontal (head in natural head position) and Frankfurt plane; length and inclination of the eye fissure; and the orbital height to eye fissure length ratio were calculated and averaged for age and sex. Comparisons were performed by factorial analysis of variance. Both the linear dimensions and the angular values were significantly larger in male subjects than in female subjects of corresponding age (p < 0.05). A significant effect of age was found (p < 0.05): while the linear distances and the orbital height-to-length ratio were greater in older people of the same sex, the inclination of the eye fissure decreased as a function of age. Both orbital inclinations were larger in the young adult group than in the adolescent and middle-aged groups. On average, the paired measurements were symmetrical, with similar values within each sex and age group. Data collected in this investigation could serve as a database for the quantitative description of human orbital morphology during normal adolescent and adult growth.

Harmonic analysis of footprint symmetry in healthy adolescents.

In the present study, the within-subject normal symmetry of footprint shape and size was analyzed from a mathematical standpoint. On the standardized left and right footprints of 83 adolescents (46 boys, 37 girls) aged 12-15 years (mean 13 years), the outline of each foot excluding the toes was identified and automatically digitized by a computerized video analyzer. Only those subjects with both left and right continuous footprints were further analyzed (36 boys, 26 girls). The footprint area was computed. The footprint shape, independent of its size, was quantified using the elliptic Fourier analysis with a 20-harmonic truncation. The symmetry in shape was quantified on an intra-subject basis by calculating a morphological distance D between the mathematical reconstructions of the left and right footprints of each subject. Symmetry in size was assessed by right-to-left area ratio. Subjects were grouped for sex, and the mean values computed. Mean footprint area was significantly larger in boys than in girls (p < 0.05). Asymmetry in size (area ratio) was 1.01 in girls, 1 in boys. Within-subject symmetry in footprint shape appeared high, with mean morphological distances of 5.95 in girls, and 6.06 in boys. No consistent associations between footprint symmetry and age, height and body weight, or shoe size were found. The mean size-independent shapes of the male and female left and right footprints were also calculated. Together with the analysis of individual asymmetry, they could be used as quantitative parameter in clinical diagnosis.

A three-dimensional quantitative analysis of lips in normal young adults.

OBJECTIVE: To supply information about (1) sex-related dimensions (linear distances and ratios, vermilion area, volume) of normal adult lips, (2) presence of sexual dimorphism, and (3) correlations between anthropometric characteristics of the lip and nose. METHODS: The three-dimensional coordinates of soft tissue landmarks on the lips and nose were obtained using an optoelectronic instrument in 90 healthy young adult women and 90 healthy young adult men. From the landmarks, several linear distances (mouth width, total vermilion height, nose height, anatomic nose width, total lip height, upper lip height), the ratio of vermilion height to mouth width, and some areas (vermilion of the upper lip, vermilion of the lower lip, total vermilion) and volumes (upper lip volume, lower lip volume, total lip volume) were calculated. Linear correlation analyses between pairs of variables were also conducted within each sex. RESULTS: All lip dimensions (distances, areas, and volumes) were significantly larger in men than in women (p<.005), but no sex differences were found in the vermilion height to mouth width ratio. Overall, mouth and nose dimensions were not significantly correlated, with the exceptions of the upper and lower lip volumes in both sexes and of the mouth and nose widths in the female sample, in which a modest part of the variance in one measurement could be explained by the other. CONCLUSION: The dimensions of the mouth and the nose did not seem to be strictly related. Data collected in the present investigation could represent a database for the quantitative description of human lip morphology in adult subjects.

Harmonic analysis of mandibular form and symmetry with computerized tomographic views.

OBJECTIVE: To quantitatively describe the isotropic (ie, orientation independent) morphologic characteristics of a standardized computed tomographic image of the mandible with the use of the elliptic Fourier series. STUDY DESIGN: Spiral CT scans parallel to the mandibular plane and enclosing both mental foramina were obtained in 17 adults (9 edentulous women, mean age, 75 years; 4 edentulous men, mean age, 68 years; and 4 dentate men, mean age, 30 years). The mandibular outline was traced, digitized, and mathematically reconstructed with the elliptic Fourier series. Mandibular area, shape, and individual symmetry were quantified. RESULTS: Mandibular area and symmetry were larger in men than in women (P <.05). In men, no effect of edentulousness was observed in either area or symmetry. Mandibular shape seemed to be influenced neither by sex nor by the presence of teeth. CONCLUSION: Mandibular size and symmetry in the analyzed computed tomographic scan (which included only the mandibular basal bone) seemed to be sex related but independent of the dental status. Mandibular shape did not seem to be modified by sex or edentulousness. Different findings may be obtained in the analysis of a section of the alveolar bone.

Soft tissue facial growth and development as assessed by the three-dimensional computerized mesh diagram analysis.

The normal growth and development of facial soft tissues from 6 years to adulthood has been studied by the 3D computerized mesh diagram analysis. The analysis allows independent quantifications of size and shape modifications both between different age groups, and between males and females. Normal age-related and sex-related references are provided. The three-dimensional facial morphometry method has been used for the collection of the x, y, z coordinates of 22 soft tissue landmarks in 2023 examinations performed on 1157 healthy white children and adolescents between 6 and 17 years of age and 191 young adults. The method detects the three-dimensional coordinates of retroreflective, wireless markers positioned on selected facial landmarks using two charge-coupled device cameras working in the infrared field. For each sex and age class, mean values were computed, and a standardized mesh of equidistant horizontal, vertical, and anteroposterior lines was consequently constructed. Within each age group, male meshes were superimposed on female meshes. Moreover, within each sex, the adult reference mesh was superimposed on the reference mesh of each age group. The global (size plus shape) difference was then evaluated by the calculation of the relevant displacement vectors for each soft tissue landmark. A global difference factor was calculated as the sum of the modules of all the displacement vectors. Consequently, a size normalization was performed, and the shape difference (size standardized) was then evaluated by the calculation of new relevant displacement vectors for each landmark, as well as a shape-global difference factor. When compared to the young adult situation, the largest child discrepancies were found in the soft tissue profile. After size standardization, shape differences were found in the forehead, nose, and chin. The soft tissue facial dimensions of boys and girls grow with similar characteristics and at the same rate between 6 and 11 years of age, but showed different patterns after this age. Within each age class, most of the sex-related differences were dimensional discrepancies that were corrected after size standardization. Nevertheless, before adolescence even these size differences were limited. On average, male faces had a larger forehead, longer and more vertical nose, more inferior and posterior gonia, more inferior and prominent lips, and a larger mouth than female faces of corresponding age.

The influence of crossbite on the coordinated electromyographic activity of human masticatory muscles during mastication.

The analysis of the masticatory muscle activity in subjects with altered occlusal relationships could provide useful data of the functional impact of morphological discrepancies. Thirty subjects aged 16-18 years, with a sound, full permanent dentition, bilateral angle class I, and an overjet and overbite between 2 and 5 mm, were examined. The control group (10 male, 10 female) had no crossbite, while the crossbite group (four male, six female) had a posterior unilateral crossbite (five on the left side, five on the right side). The electromyographic activity of the left and right masseter and temporalis anterior muscles was recorded during 15 s of unilateral (left and right) chewing of gum, and expressed as a percentage of the maximum voluntary clench on cotton rolls. For each subject, the masticatory frequency, the confidence ellipse of the simultaneous differential left-right masseter and temporal activity (Lissajous figure), and an index of muscular symmetry, were computed to assess muscular coordination. In the crossbite subjects, the four analysed muscles appeared to contract with altered and asymmetric patterns. A large variability was found, and the confidence ellipses calculated for the chewing tests performed on the crossed sides were not significant, while the confidence ellipses of the uncrossed side chewing were different from the ellipses computed in the normal occlusion group. The altered occlusal relationship influenced the coordination of the masticatory muscles during chewing on both sides. The functional alteration was more apparent when the side with the altered morphology was directly involved, i.e. when chewing was performed on the crossbite side.

Three-dimensional dental arch curvature in human adolescents and adults.

The three-dimensional arrangement of dental cusps and incisal edges in human dentitions has been reported to fit the surface of a sphere (the curve of Monson), with a radius of about 4 inches in adults. The objective of the current study was to compare the three-dimensional curvature of the mandibular dental arch in healthy permanent dentitions of young adults and adolescents. The mandibular casts of 50 adults (aged 19 to 22 years) and 20 adolescents (aged 12 to 14 years) with highly selected sound dentitions that were free from temporomandibular joint problems were obtained. The three coordinates of cusp tips excluding the third molars were digitized with a three-dimensional digitizer, and used to derive a spherical model of the curvature of the occlusal surfaces. From the best interpolating sphere, the radii of the left and right curves of Spee (quasi-sagittal plane) and of molar curve of Wilson (frontal plane) were computed. Mandibular arch size (interdental distances) was also calculated. The occlusal curvature of the mandibular arch was not significantly influenced by sex, although a significant effect of age was found (Student t, P <.005). The radii of the overall sphere, right and left curves of Spee, and curve of Wilson in the molar area were about 101 mm in adults, and about 80 mm in adolescents. Arch size was not influenced by either sex or age. The different curvatures of the occlusal plane in adolescents and adults may be explained by a progressive rotation of the major axis of the teeth moving the occlusal plane toward a more buccal position. These dental movements should be performed in a frontal plane on an anteroposterior axis located next to the dental crown.

Size and shape of the human first permanent molar: a Fourier analysis of the occlusal and equatorial outlines.

Form can be viewed as a combination of size and shape. Shape refers to the boundary outline independently from its orientation, relation to reference planes, and dimension (or size). Shape and its changes could be quantified by mathematical methods such as the Fourier series. In this investigation, Fourier analysis has been used to quantify the morphologic characteristics (size and shape) of the outline of the occlusal surface and maximum circumference (equator) in 259 normal, healthy human first permanent maxillary and mandibular molars and to assess the effect of sex. Large within-group variability was found in the Fourier coefficients. Both equatorial and occlusal molar areas were on average larger in male than in female homologous teeth, but the difference was statistically significant only for the equatorial areas. The mean ratios between equatorial and occlusal dental areas were independent from arch (maxillary and mandibular), side, or sex. Both equatorial and occlusal outlines of left and right homologous molars within sex and arch were similar, without size and shape differences. Similarly, no sex differences in shape were found in the comparison of homologous teeth. The method used in the present study could supply information about dental shape in both its entirety and local variations. In particular, the method is extremely sensitive to local variations in dental shape, and it could be usefully employed to compare single teeth to a standard.

The effects of a single intercuspal interference on electromyographic characteristics of human masticatory muscles during maximal voluntary teeth clenching.

In 13 healthy subjects (eight men and five women, mean age, 22 years), an aluminum intercuspal interference (height, 0.25 mm) was placed on the maxillary right first premolar to study its effect on the contractile symmetry of the right and left masseter and anterior temporalis muscles when measured through a Percentage Overlapping Coefficient (POC), derived from surface electromyographic recordings of maximum voluntary teeth clenching. Additionally, and to estimate the potential of the experimental intercuspal interference to induce lateral displacement of the mandible, a Torque Coefficient (TC) was derived from surface electromyographic recordings. The conclusion was that the experimental occlusal interference gave rise to asymmetric contractile activity in the studied mandibular elevator muscles as well as a potential to displace the mandible in a lateral direction.

Morphometry of the normal human ear: a cross-sectional study from adolescence to mid-adulthood.

The objective of this study was to supply information about: (1) normal gender-based dimensions of ears (linear distances and ratios, area); (2) left right symmetry; and (3) growth changes between adolescence and mid-adulthood. The three-dimensional co-ordinates of several soft-tissue landmarks on the ears and face were obtained by an electromagnetic digitizer in 40 male and 33 female adolescents aged 12-15 years. 73 young female and 89 young male adults aged 19-30 years, and 41 male and 38 female adults aged 31-56 years. From the landmarks, paired car width and length were calculated and averaged for age and gender, as well as the relevant ratios, ear areas and angles relative to the facial midline, and indices of left right symmetry. Comparisons were performed by factorial analysis of variance. All ear dimensions were significantly larger in men than in women (P < 0.005). A significant effect of age was found (P < 0.005), with larger values in older individuals. On average, the three-dimensional position of ears was symmetric, with symmetry coefficients ranging between 94 and 96%. Data collected in the present investigation could serve as a database for the quantitative description of human ear morphology during normal adolescent and adult growth.

Reliability of soft tissue references for anteroposterior measurement of dental bases.

The aims of the present investigation were to devise a new anteroposterior measurement of maxillomandibular discrepancies that would consider both hard and soft tissue contributions, and to verify the correlation of this measurement to a well-established linear assessment of anteroposterior discrepancy. On the pretreatment lateral cephalographs of 300 orthodontic patients (162 males, 138 females) aged between 6 and 50 years, the Wits appraisal and a new "soft tissue" Wits appraisal (linear distance between the projections of soft tissue A and B points on the bisecting occlusal plane) were measured. In the analyzed sample, the former was more variable than the latter. The two measurements were significantly correlated to each other without sex- or age-characteristic patterns. From the correlation, reference values for the new measurement were estimated and found to be between -1.9 mm and 5.4 mm for individuals with a normal occlusion. The new measurement could allow a more careful evaluation of the soft tissue drape together with the underlying hard tissue structure.

A three-dimensional computerized mesh diagram analysis and its application in soft tissue facial morphometry.

A modified computerized mesh diagram analysis that allows rapid and independent quantifications of soft tissue facial size and shape in the three-dimensional space is presented. Normal references are provided, and the application of the method is also exemplified by the analysis of two maxillofacial surgical patients. The Three-Dimensional Facial Morphometry method has been used for the collection of the x, y, z coordinates of 22 soft tissue landmarks in 50 men and 50 women (all healthy young white adults). The method detects the three-dimensional coordinates of retroreflective, wireless markers positioned on selected facial landmarks with two charge-coupled device cameras, working in the infrared field. The midpoint between the right and left tragus landmarks served as the origin of the coordinate axes, and the landmark coordinates were rotated, setting the intercantheal line horizontal on both the frontal and the horizontal planes, and the Camper's plane inclined at -7.5 degrees on the sagittal plane. A standardized mesh of equidistant horizontal (dimension: half the upper face width), vertical (half the vertical projection of upper face height), and anteroposterior (half the horizontal projection of upper face depth) lines was consequently constructed. The lattice was replicated on the entire face and comprised 84 parallelepipeds. Both male and female reference meshes had a harmonious and symmetric appearance, with gender differences in facial size but not in facial shape. The standard normal reference was superimposed on the patient's tracing, and the global (size plus shape) difference was then evaluated by the calculation of the relevant displacement vectors for each soft tissue landmark. A global difference factor was calculated as the sum of the modules of all the displacement vectors. Consequently, a size normalization was performed, and the shape difference (size-standardized) was then evaluated by the calculation of new relevant displacement vectors for each landmark, as well as a shape--global difference vectors.