Preliminary approach for the surface electromyographical evaluation of the oral phase of swallowing.

Swallowing is a muscular activity that occurs both after mastication and spontaneously as a result of saliva accumulation. Spontaneous saliva swallowing occurs about every 2 minutes. Comprehension of its functional mechanisms is relevant to assess their modification in clinical situations. A standardised surface electromyographical (ssEMG) protocol for the evaluation of this muscle activity is lacking. Aims of the present study are: (i) to determine the reproducibility of a ssEMG protocol for the evaluation of the oral phase of saliva swallowing and (ii) to evaluate the activity of masseter (MM), anterior temporalis (TA), submental muscles (SM) to draw a reference model of swallowing. Standardised surface electromyographical activity of MM, TA and SM during swallowing of saliva spontaneously accumulated was recorded in 20 healthy participants. Functional indexes including symmetry (POC), recruitment (Impact), duration of activation of each couple of muscles and of the whole exercise, position, intensity of the spike were computed. Inter- and intra-appointment reliabilities were assessed and method errors calculated. Descriptive statistics, sex- and muscles-related comparisons were carried out. Standardised surface electromyographical assessment of MM, TA and SM muscles was reliable. A high inter-individual variability was found. Percentage overlapping coefficient (POC) values were close to 80% for TA and SM, higher than for MM (P < .001). Impact values ranged between 16.4% and 30.7%, and differences were found between muscles (P < .001). The global muscle activity during swallowing lasted between 1.5 and 1.8 seconds. For each couple of muscles, the duration of activation ranged between 0.7 and 1.6 seconds and muscles-related differences were found (P < .001). The spike of activation for each couple of muscle ranged between 35.7% and 44.2% of the duration. The protocol was reliable and intra-participants repeatable measures can be carried out. Due to the high inter-participants variability, further analyses are needed to draw a model of muscular activity.

Electromyographic assessment of jaw muscles in patients with All-on-Four fixed implant-supported prostheses.

This study evaluated the electromyographic (EMG) characteristics of masticatory muscles in patients with fixed implant-supported prostheses according to All-on-Four(®) principles and in control healthy dentate subjects. Twenty-six subjects aged 50-74 years were examined. Eighteen were edentulous and had been successfully rehabilitated with (i) mandibular All-on-Four(®) implant-supported fixed prostheses and maxillary complete dentures (10 patients) and (ii) mandibular and maxillary All-on-Four(®) implant-supported fixed prostheses (eight patients). Eight reference subjects had natural dentition. Surface EMG recordings of the masseter and temporalis muscles were performed during maximum voluntary teeth clenching and during unilateral gum chewing. All values were standardised as percentage of a maximum clenching on cotton rolls. During clenching, a good global neuromuscular equilibrium was found in all participants. During chewing, all groups had similar values of working-side muscle activities and of chewing frequency. No significant differences in the analysed EMG parameters were found between the patients with mandibular and maxillary All-on-Four(®) implant-supported prostheses and the reference subjects. In contrast, standardised pooled muscle activities and standardised muscular activities per cycle were larger in patients with a maxillary removable prosthesis than in control subjects (Kruskal-Wallis test, P < 0·01). Also, patients wearing a complete maxillary denture showed a poor neuromuscular coordination with altered muscular pattern and lower values of the index of masticatory symmetry than dentate control subjects (P < 0·01). EMG outcomes suggest that All-on-Four(®) implant-supported prostheses may be considered a functionally efficient treatment option for the rehabilitation of edentulous patients with reduced residual bone volume.

Relationship between facial morphology and cervical vertebral shape: a radiographic investigation.

AIM: The aim of this study was to investigate the relationships between the characteristics of cervical vertebrae and craniofacial morphology using a global mathematical method. METHODS: Several cephalometric measurements and the outlines of the second (C2) and fourth (C4) cervical vertebrae were obtained from 45 head films (32 females aged 20-40 years; 13 males aged 21-37 years). Vertebral outlines were mathematically obtained by Fourier series, and the morphological distance between each outline and a reference one was computed. Linear correlations were run between cephalometric variables and morphological distances. RESULTS: Significant correlations (P<0.05) were found between anterior cranial base length (sella-nasion) and the morphological distance of C4 (subjects with a longer cranial base differ more from the reference vertebral outline), and between maxillary length and the morphological distance of C2 (subjects with a shorter maxilla differ more from the reference vertebral outline). The relationship between mandibular base length (Go-Me) and the morphological distance of C2 (subjects with a shorter mandible differ more from the reference vertebral outline) was nearly significant. Within each subject, the two analyzed vertebrae had independent relationships with the reference outlines. CONCLUSION: A significant but limited relationship between craniofacial structures and vertebral morphology was found: at the best, 10% of the differences between the individual vertebral morphology and the reference one may be explained by craniofacial cephalometric measurements. The differences found between C2 and C4 morphologies may show a different effect of suboccipital muscles and of neck muscles within the theories of the functional matrix hypothesis.

Palate morphology of bruxist children with mixed dentition. A pilot study.

The objective of the study was to analyse quantitatively palatal morphology in bruxist and non-bruxist children with mixed dentition. Twenty-three children with mixed dentition were classified as bruxist according to their anxiety level, audible occlusal sounds related by the parents and signs of temporomandibular disorders; 23 children were control subjects matched for gender, age, and dental formula. The maxillary dental arches of all subjects were reproduced from alginate impressions cast in dental stone with a standardized technique. The casts were digitalized and mathematical equations were used to obtain the form of the palate in the sagittal, frontal and horizontal planes. Bruxist children had a statistically significant longer palate in the sagittal plane than control children; palatal shape differed especially in correspondence of the third, fourth and fifth teeth, bruxist children showing a relatively higher palate than control children. In this pilot study, sagittal plane differences in the palate between bruxist and non-bruxist children matched for age and gender were found. Further investigations are needed to understand better the clinical implications of the findings. Results should be taken into account in the diagnosis of the occlusal development in children with parafunctions to prevent future abnormalities: a bruxist child may have bigger dental arches than a normal child.

Anatomy of emotion: a 3D study of facial mimicry.

Alterations in facial motion severely impair the quality of life and social interaction of patients, and an objective grading of facial function is necessary. A method for the non-invasive detection of 3D facial movements was developed. Sequences of six standardized facial movements (maximum smile; free smile; surprise with closed mouth; surprise with open mouth; right side eye closure; left side eye closure) were recorded in 20 healthy young adults (10 men, 10 women) using an optoelectronic motion analyzer. For each subject, 21 cutaneous landmarks were identified by 2-mm reflective markers, and their 3D movements during each facial animation were computed. Three repetitions of each expression were recorded (within-session error), and four separate sessions were used (between-session error). To assess the within-session error, the technical error of the measurement (random error, TEM) was computed separately for each sex, movement and landmark. To assess the between-session repeatability, the standard deviation among the mean displacements of each landmark (four independent sessions) was computed for each movement. TEM for the single landmarks ranged between 0.3 and 9.42 mm (intrasession error). The sex- and movement-related differences were statistically significant (two-way analysis of variance, p=0.003 for sex comparison, p=0.009 for the six movements, p<0.001 for the sex x movement interaction). Among four different (independent) sessions, the left eye closure had the worst repeatability, the right eye closure had the best one; the differences among various movements were statistically significant (one-way analysis of variance, p=0.041). In conclusion, the current protocol demonstrated a sufficient repeatability for a future clinical application. Great care should be taken to assure a consistent marker positioning in all the subjects.

Two-dimensional vs three-dimensional assessment of soft tissue facial profile: a non invasive study in 6-year-old healthy children.

AIM: In medical practice, the analysis of facial soft tissues often complement (or even supplement) the evaluation of the hard-tissue relationships. Current technology provides reference data in three dimensions, but clinical practice still uses two-dimensional photographs. In the current study, two-dimensional photographic and computerized, three-dimensional angles measured on the facial profile of children were compared. METHODS: Two-dimensional angular measurements (facial convexity including/excluding the nose; maxillary prominence; nasal prominence; nasolabial; mentolabial; maxillo-labio-mandibular; interlabial) were obtained on the facial profile photographs of 55 boys and 31 girls aged 6; measurements were compared to three-dimensional computerized data collected on 27 boys and 28 girls of the same age and ethnic group. RESULTS: On average, in boys, only the angles of facial convexity including the nose, interlabial, nasolabial and maxillo-labio-mandibular showed differences between the means larger than 2 degrees (up to 2.5 degrees). Statistically significant differences (P<0.05, Watson-Williams' test) were found for the angle of facial convexity including the nose and the maxillary prominence angle. In girls, differences between the two methods larger than 2 degrees were found for the interlabial, maxillo-labio-mandibular (statistically significant), and mentolabial angles (differences up to 7 degrees, corresponding to 4% of the relevant mean). CONCLUSION: The two-dimensional photographic and the three-dimensional computerized data compared in the current study, even not superimposable, seemed sufficiently interchangeable, at least from a clinical point of view. A particular attention should be given to the recording of lip position.

Morphometry of the ear in Down's syndrome subjects. A three-dimensional computerized assessment.

The three-dimensional coordinates of 13 soft-tissue landmarks on the ears were obtained by a computerized digitizer in 28 subjects with Down's syndrome aged 12-45 years, and in 449 sex, age and ethnic group matched controls. From the landmarks, left and right linear distances (ear width and length), ratios (ear width-to-ear length), areas (ear area), angles (angle of the auricle versus the facial midplane) and the three-dimensional symmetry index were calculated. For both males and females, all linear dimensions and areas were significantly (Analysis of Variance, P < 0.001) larger in the reference subjects than in the subjects with Down's syndrome. All values significantly increased as a function of age (P < 0.05); the increment was larger in the reference subjects than in the subjects with Down's syndrome. On both sides of the face, the subjects with Down's syndrome had larger ear width-to-ear length ratios, and larger angles of the auricle versus the facial midplane than the reference subjects. The three-dimensional symmetry index was significantly larger in the reference subjects and in the older persons. In conclusion, ear dimensions, position and shape significantly differed in subjects with Down's syndrome when compared to sex, age and ethnic group matched controls. Some of the differences were sex and age related.

Body movements on the men's competition mushroom: a three dimensional analysis of circular swings.

OBJECTIVES: To develop a method for the three dimensional analysis of body movements and body positions during the performance of circular swings on the competition mushroom, an apparatus used by young gymnasts for pommel horse training. METHODS: Five experienced male gymnasts, all of national level, performed three series of 10 circular swings on the competition mushroom. An optoelectronic instrument was used for the detection of the three dimensional movement of 13 body landmarks. From landmark trajectories, several technical measurements were obtained: diameters of ideal circles of ankles, hips, shoulders; deviation of the ankle diameters from circularity and from the horizontal plane; angle between the shoulder, hip, and ankle. The values were used for a quantitative assessment of performance of the five gymnasts. RESULTS: During the exercise, each ankle should follow a nearly horizontal circular path (deviation from circularity ranged from 3.6% to 6%, deviation from horizontality was 9.4-19.7%), there should be an angle of about 180 degrees at the hips (actual values 146-153 degrees ), and the shoulders should move as little as possible, and only in the lateral plane, without major anteroposterior movements (shoulder movement was 27-31% of ankle movement, hip movement was 16-20%). CONCLUSIONS: The method could help coaches and gymnasts to determine which parts of the body are not repeating a selected movement with sufficient accuracy and to quantify improvements made after a specific training programme.

Facial changes in adult uremic patients on chronic dialysis: possible role of hyperparathyroidism.

BACKGROUND: Uremic patients on regular dialytic treatment (RDT) are often affected by a complex metabolic syndrome leading to osteodystrophy. Bone changes are primarily due to high bone turnover, often combined with a mineralization defect leading to increased bone fractures and bone deformities. Although rarely considered, the craniofacial skeleton represents one of the peculiar targets of this complex metabolic disease whose more dramatic pattern is a form of leontiasis ossea. This complication, although described, has never been evaluated in depth nor quantitatively assessed. In order to assess facial deformities in uremic conditions and to understand the possible relation with hyperparathyroidism, we undertook a quantitative evaluation of soft facial structures in a cohort of uremic patients undergoing RDT. METHODS: The three-dimensional coordinates of 50 soft-tissue facial landmarks were obtained by an electromagnetic digitizer in 10 male and 10 female patients with chronic renal insufficiency aged 53-81 years, and in 34 healthy individuals of the same age, ethnicity and sex. Uremic patients were enrolled according to hyperparathyroid status (PTH < 300 pg/mL and PTH > 500 pg/mL). From the landmarks, facial distances, angles and volumes were calculated according to a geometrical face model. RESULTS: Overall, the uremic patients had significantly larger facial volumes than the reference subjects. The effect was particularly evident in the facial middle third (maxilla), leading to an inversion of the mandibular-maxillary ratio. Facial dimensions were increased in all three spatial directions: width (skull base, mandible, nose), length (nose, mandible), and depth (mid face, mandible). The larger maxilla was accompanied by a tendency to more prominent lips (reduced interlabial angle). Some of the facial modifications (nose, lips, mandible) were significantly related to the clinical characteristics of the patients (age, duration of renal insufficiency and PTH levels). CONCLUSIONS: This report, the first in the literature, shows that facial structures of uremic patients are enlarged in comparison with matched normal subjects and that increased bone turnover could be responsible--at least in part--for facial bone changes.

Shape of the human corpus callosum. Elliptic Fourier analysis on midsagittal magnetic resonance scans.

RATIONALE AND OBJECTIVES: Sex, age, or functional-asymmetry-related variations in the size and shape characteristics of the midsagittal magnetic resonance (MR) image of the human corpus callosum (CC) have been widely investigated in the last 10 years, with conflicting results. In the current study, the authors attempted to analyze the sex- and age-related shape differences of the human CC in a large sample of adult subjects from a mathematical standpoint. METHODS: On the midsagittal MR images of 143 neurologically intact adults (75 women, 68 men, 21 to 81 years of age) the outline of the CC was identified. The shape of the CC was quantified using elliptic Fourier analysis, which allows for a global evaluation of the shape of organs identified by their outlines independent of their size, spatial orientation, and relation to reference planes. Subjects were grouped by sex and age. RESULTS: The shape of the human CC within age and sex class was highly variable. The analysis of variance showed a significant effect of age; however no significant sex differences could be demonstrated. CONCLUSIONS: Larger sample sizes are required to definitively assess the normal shape variations in human CC. The method developed also could be applied to the comparison of healthy and diseased individuals.

Shape of the human corpus callosum in childhood. Elliptic Fourier analysis on midsagittal magnetic resonance scans.

RATIONALE AND OBJECTIVES: The authors previously investigated the midsagittal magnetic resonance images of neurologically intact adults, and analyzed the shape of corpus callosum from a mathematic standpoint. Significant effects of age were demonstrated, without significant sex differences. In the current study, the same mathematic method was applied to analyze the sex and age shape differences of the human corpus callosum in childhood. METHODS: On the midsagittal magnetic resonance images of 84 neurologically intact children (39 boys, 45 girls, aged 4 months to 15 years) the outline of the corpus callosum was identified. Its shape was quantified using elliptic Fourier analysis, which allows for global evaluation of the shape of organs identified by their outlines independently from size, spatial orientation, and relationship to reference planes. Subjects were grouped by sex and age. RESULTS: The shape of the corpus callosum within age and sex classes in childhood was more homogeneous than in adulthood. A significant effect of age was demonstrated by the analysis of variance; however, no significant sex differences were found. CONCLUSIONS: Corpus callosum shape in midsagittal magnetic resonance images was strongly influenced by central nervous system development and aging, but the influence of sex was not sufficient to be detected by current standard magnetic resonance imaging technology, and by the available sample sizes. The current investigation supplies data on the normal callosal shape in the first two decades of life, thus completing previous analysis.

Quantitative analysis of penile ultrasonographic shape during the erectile cycle: a new diagnostic tool for erectile dysfunction? Repeatability of the method and preliminary results.

Penile modifications during erection interest not only penile length and circumference, but also its size and shape. In this investigation, the size and shape repeatability of a single standardized ultrasonographic image of penis during flaccidity and erection was quantified in a group of 19 patients complaining of erectile dysfunction. The penis of each patient was placed in the dorsal position and scanned by a 10 MHz linear ultrasonographic probe at the site of maximal corporeal size: (1) during flaccidity; (2) after an intracorporeal injection of 10 micrograms alprostadil; and (3) after a genital stimulation. Each scan was repeated three times for each patient and printed. On each print the outline of the tunica albuginea was drawn, digitized, and mathematically reconstructed by Fourier series that allow a separate quantification of the size and shape differences. Reliability of the tunica albuginea outline and repeatability of probe positioning were separately assessed within patient and functional phase, and found to be good. The actual examinations of two impotence patients performed using the described method are also given. The shape of the corpora cavernosa may be potentially indicative of the homogeneous function of the tunica albuginea, and it may be of use in patients' follow up.

Foot asymmetry in healthy adults: elliptic fourier analysis of standardized footprints.

The size and shape of paired structures differ in the left and right sides of the body. Shape characteristics should be analyzed separately from size to supply information about the normal variations of human organs. 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 46 healthy adults (23 women and 23 men; 19-26 years old), the outline of each foot excluding the toes was identified and its shape was quantified independently from size by the elliptic Fourier analysis. The symmetry in shape was quantified on an intra-subject basis by calculating a morphologic distance D between the mathematical reconstructions of the left and right footprints of each subject. Symmetry in size was assessed by the right-to-left area ratio and found to be very good for all subjects; it ranged from 0.948 to 1.049. The subjects were also grouped by sex, and mean values were calculated. Within-subject symmetry in the footprint shape appeared high, with morphologic distances ranging between 8.94 and 2.66 in men and between 7.15 and 3.09 in women. No consistent associations between footprint symmetry and age, body height and weight, or shoe size were found. On average, women had more symmetric size-standardized footprints than did men (women: mean 4.57, SD 1.14; men: mean 5.46, SD 1.7; p < 0.05). Mean size-independent shapes of male and female left and right footprints were also calculated. Together with the analysis of individual asymmetry, they could be used for the quantitative diagnosis of borderline patients.

Statistical evaluation of Monson's sphere in healthy permanent dentitions in man.

The three-dimensional curvature of the mandibular dental arch was studied in 20 men and 20 women with sound dentitions and free from temporomandibular joint problems. The x, y, z coordinates of cusp tips of all but the third molars were obtained 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 the canine and molar curves of Wilson (frontal plane) were computed. The occlusal curvature of the mandibular arch was not significantly influenced by gender, even if, on average, all the computed variables were larger in men than women. The radii of the overall sphere, right and left curves of Spee, and curve of Wilson in the molar area were about 105 mm in men, and about 100 mm in women. A relatively large intrasample variability in arch curvature was found. The mean sphere radius in men was very close to the classical value of 4 in, confirming Monson's observations, but the relatively large intrasample variability prevented any definitive determination of a sexual dimorphism in the three- dimensional characteristics of occlusal curvature.

Mathematical definition of the curve of Spee in permanent healthy dentitions in man.

The intrinsic morphology of the mandibular curve of Spee (i.e. independent from reference planes) was studied in 50 men and 45 women with sound dentitions. Left and right curves were reconstructed by a second-order quadratic interpolation of buccal cusp tips. Gender differences were found in both sides, while side differences were found only in the male sample. Male and female curves had similar concavities, but the position of the interpolating second-order quadratic curve relative to the dental arch was significantly different. The right and left male sides showed different concavities, the right-hand side being flatter than the left. Male curves appeared larger than female ones, and the left-hand side was significantly larger than the right regardless of gender. The reported second-order quadratic curves could be used as reference for prosthetic and orthodontic reconstructions.

Maxillary versus mandibular arch form differences in human permanent dentition assessed by Euclidean-distance matrix analysis.

Euclidean-distance matrix analysis (EDMA) was used to analyse the dental arch form in 50 men and 45 women aged 20-27 yr with sound dentitions. Fourteen landmarks, corresponding to the centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar), were identified on the dental casts of subjects. All the possible linear distances between pairs of teeth were computed and maxillary/mandibular arch differences within sex were tested by EDMA. In both sexes, the maxillary arch was larger than the mandibular arch; arch shape was also significantly different. All teeth contributed to the shape difference between arches regardless of gender. EDMA also separated the influence of anterior and posterior teeth in the determination of upper/lower arch characteristics.

Dental arch asymmetry in young healthy human subjects evaluated by Euclidean distance matrix analysis.

Form differences between biological structures can be evaluated using several approaches. A recently proposed method (Euclidean distance matrix analysis; EDMA) seems to be able to differentiate between size and shape differences. Here it has been applied to study the asymmetry of mandibular and maxillary arches in 50 men and 45 women with sound dentitions. The centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar) were individualized on the dental casts of subjects. The form of the right and left maxillary and mandibular hemi-arches was separately assessed by calculating all the possible linear distances between pairs of teeth within arch and side. Side differences were tested by EDMA. In men, the maxillary and the mandibular arches were both symmetrical (i.e. there were no significant differences in size or shape between the left and right hemi-arches). In women, the mandibular arch was symmetrical, but in the maxillary arch the two antimeres had a significantly different shape. No size differences were found between the left and right female hemi-arches.

A computerized non-invasive method for the assessment of human facial volume.

The three-dimensional coordinates of 22 standardized soft-tissue facial landmarks were used in the definition of a three-dimensional model of the adult human face. The model allows the estimation of the volume of the face in toto and of its parts (upper, middle and lower thirds, nose). Landmark coordinates were collected in 80 healthy young adults (40 men and 40 women selected according to criteria of dentofacial normality) by infrared photogrammetry by an automated instrument, and facial volumes calculated. Sample variability was larger in women than in men; the nose and the upper third of face had the largest variability regardless of gender. On average, all volumes computed in men were significantly larger than the corresponding values computed in women. Also the lower-to-middle third face ratio was significantly higher in men than in women. The sexual dimorphism in human facial volume did not involve the different parts of the face to the same extent: a large part of male facial volume preponderance was explained by the lower third of face. The proposed facial model could adequately represent the human face in all those research and clinical fields where noninvasive surface measurements could be employed alone or in support of conventional radiographic data.

Soft-tissue facial morphometry from 6 years to adulthood: a three-dimensional growth study using a new modeling.

A recently introduced three-dimensional computerized system with landmark representation of the soft-tissue facial surface allows noninvasive and fast quantitative study of facial growth. The aims of the present investigation were (1) to quantify growth changes in soft-tissue facial morphology, (2) to evaluate sex differences in growth patterns, and (3) to provide reference data for selected angular and linear measurements that could be of interest for the objective analysis of maxillofacial surgery or orthodontic patients. The three-dimensional coordinates of 22 standardized facial landmarks were automatically collected by automated infrared photogrammetry using the three-dimensional facial morphometry method in a mixed longitudinal and cross-sectional study, in which 2023 examinations were obtained in 1348 healthy nonpatient subjects between 6 years of age and young adulthood. Selected parameters (angles, linear distances, and ratios) were calculated and averaged for age and sex. Male values were compared with female values by means of Student's t test. Within each age group, linear distances were significantly larger in boys than in girls (p < 0.05) with some exceptions coinciding with the earlier female growth spurt, whereas angular measurements did not show a corresponding sexual dimorphism. Linear distances in girls had almost reached adult dimensions in the 12-to-13-year-old age group, whereas in boys a large increase was still to occur. This was most evident in the middle third of the face, where both sexes showed almost the same dimension and amount of growth up to the age of 13, with significant differences afterward, boys being larger than girls. On the contrary, in the lower third of the face, significant differences occurred throughout the whole investigated period, boys being always larger than girls. The male versus female angular comparison reflected the differential timing in attainment of adult proportions. The three-dimensional facial morphometry method allowed the noninvasive evaluation of a large sample of nonpatient subjects, leading to the definition of three-dimensional normative data about facial soft tissues. The method could supplement more invasive radiographic evaluations, allowing frequent examinations of children and adolescents before and during treatment, as well as in the follow-up.

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.