Morphometry of the ear in north Sudanese subjects with Down syndrome: a three-dimensional computerized assessment.

Down syndrome (DS) is the most frequent live-born autosomal aneuploidy in humans. Scanty data on the craniofacial phenotype of African subjects with DS have been published so far. We wanted to detail the morphologic characteristics of the ears in north Sudanese subjects with DS. The three-dimensional coordinates of 13 soft-tissue landmarks on the ears were obtained using a laser scanner in 64 north Sudanese subjects with DS aged 4 to 34 years and in 682 sex- and age-matched control subjects. 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 vs the facial midplane), and the three-dimensional symmetry index were calculated. Distances, angles, areas, and ratios were computed. Subject and reference data were compared by computing z scores and calculating Student t tests. Ear width, length, and area were significantly (Student t test, P < 0.001) smaller in the subjects with DS than in the reference subjects. On the right side of the face, the subjects with DS 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. In conclusion, ear dimensions, position, and shape significantly differed in subjects with DS when compared with sex-, age-, and ethnic group-matched control subjects.

Three-dimensional assessment of nose and lip morphology in North Sudanese subjects with Down syndrome.

OBJECTIVE: To detail the nasolabial morphologic characteristics of North Sudanese subjects with Down syndrome (DS). MATERIALS AND METHODS: Nasolabial morphology was assessed three-dimensionally in 64 North Sudanese subjects with DS aged 4 to 34 years and in 682 sex- and age-matched controls. Three-dimensional facial coordinates were collected using a laser scan, and selected distances, angles, areas, and volumes were computed. Subject and reference data were compared by computing z-scores and Student's t-tests. RESULTS: The nose was significantly smaller (area) in subjects with DS than in reference subjects, and it had a different shape (more flat angle of alar slope, more acute nasal tip angle). The vertical (nasal bridge length, nose height) and anteroposterior (nasal tip protrusion) dimensions were reduced, while the horizontal dimensions (alar base width, inferior widths of the nostrils) were increased. The nasolabial angle was increased. The cutaneous lip volume was significantly smaller, while the vermilion lip area was larger in the subjects with DS. The mouth and philtrum widths were significantly reduced, while the vermilion height was significantly increased. CONCLUSION: Analyzed subjects with DS had a hypoplastic nose and different upper and lower lips than did reference, normal subjects.

Non-invasive longitudinal assessment of facial growth in children and adolescents with hypohidrotic ectodermal dysplasia.

Facial growth patterns in 12 subjects (six boys and six girls) with hypohidrotic ectodermal dysplasia (HED) were analyzed and compared with facial growth patterns obtained in healthy reference peers. All subjects with HED were aged 7 yr (mean age +/- standard deviation: 7.08 +/- 0.41 yr) at the first examination and 14 yr (mean age +/- standard deviation: 14.56 +/- 0.34 yr) at the last examination. In each subject, the three-dimensional coordinates of facial landmarks were collected non-invasively at eight subsequent years. The volumes of forehead, nose, maxilla and mandible, upper lips, and lower lips were estimated. For each facial volume, differential values between different time points were calculated individually, separately for the 'childhood' (7-10 yr) and the 'adolescence' (11-14 yr) growth period in both HED and reference subjects. Children and adolescents with HED had a slightly reduced global facial growth in comparison with normal reference peers. The peak mandibular and maxillary development was delayed by approximately 2 yr towards later adolescence. The present non-invasive system seems to be useful for studying longitudinal changes of facial growth in healthy and syndromic subjects.

Fatigue in the sternocleidomastoid muscle and hip dysplasia: a surface electromyographic assessment in adult women.

OBJECTIVE: The aim of this study is to assess a possible relationship between unilateral hip dysplasia and sternocleidomastoid muscle function during a fatiguing task. METHODS: In this patient-control, cross-sectional study, 11 female patients (aged 37-63 years) with unilateral coxoarthrosis subsequent to hip dysplasia and 9 female control subjects matched for age were assessed. Surface electromyography of the right and left sternocleidomastoid muscles was measured in the women performing a standardized endurance test. The median power frequency was calculated at the beginning (T0) and at the end of the task (T1, endurance time). For each subject and muscle, percentage decrements in the median power frequency were computed at T1. RESULTS: Endurance time ranged between 15 and 125 s (control group), and 10 and 200 s (patient group), without a significant difference between the 2 groups (Mann-Whitney test, P > .05). In the patient group, no significant differences in the median power frequency between the ispilateral to coxoarthrosis and contralateral sides were found (Wilcoxon test, P > .05). The percentage decrements of the median power frequency in the control (right and left side pooled) and patient group did not significantly differ either in the ispilateral to coxoarthrosis and contralateral sides (Mann-Whitney test, P > .05). CONCLUSIONS: The lack of significant differences between the sternocleidomastoid muscles of healthy women and those of women with hip dysplasia does not support the presence of a common noxa causing both congenital muscular torticollis and hip joint alterations. Alternatively, the coexistence of the 2 alterations in infancy may disappear during adult life.

A quantitative three-dimensional assessment of abnormal variations in the facial soft tissues of individuals with Down syndrome.

OBJECTIVE: To supply quantitative information about the facial soft tissues of subjects with Down syndrome by using summary anthropometric measurements. DESIGN, SETTING, AND PATIENTS: The three-dimensional coordinates of soft tissue facial landmarks were obtained using a computerized digitizer in 28 subjects with Down syndrome (11 girls and women and 17 boys and men aged 12 to 45 years) and 429 healthy controls matched for sex, age, and ethnicity. From the landmarks, 18 facial dimensions were calculated. Data were compared with those collected in healthy individuals by computing z-scores. Two summary anthropometric measurements for quantifying craniofacial variations were assessed in both the subjects with Down syndrome and the reference subjects: the mean z-score (an index of overall facial size) and its standard deviation, craniofacial variability index (an index of facial harmony). RESULTS: In subjects with Down syndrome, facial size was smaller than in normal individuals, and in 17 subjects the mean z-score fell outside the normal interval (mean +/- 2 SD). Twenty subjects had a craniofacial variability index larger than the normal interval. CONCLUSIONS: The facial soft tissue structures of subjects with Down syndrome differed from those of normal controls of the same age, sex, and ethnic group: a reduced facial size was coupled with a global anomalous relationship between individual measurements. The two indices allowed discriminating more than 89% of subjects with Down syndrome when compared with normal subjects.

Three-dimensional assessment of nose and lip morphology in subjects with down syndrome.

Nasolabial morphology was assessed 3-dimensionally in 28 subjects with Down syndrome aged 12-45 years and in 449 sex- and age-matched controls. Subject and reference data were compared by computing z scores and calculating Student's t tests. The nose was significantly smaller (volume, area) in the subjects with Down syndrome than in the reference subjects, and it had a different shape (more flat angle of alar slope, more acute nasal tip angle). The vertical (length of the nasal bridge, height of the nose) and anteroposterior (nasal tip protrusion) dimensions were reduced, while the horizontal dimensions (alar base width, superior and inferior widths of the nostrils) were increased. The lower lip was significantly smaller (volume, area, vermilion height), while the upper lip was larger (area, vermilion height) in the subjects with Down syndrome. The mouth width was also significantly smaller. In conclusion, the analyzed subjects with Down syndrome had a hypoplastic nose and different upper and lower lips than reference, normal subjects.

Soft-tissue facial areas and volumes in individuals with ectodermal dysplasia: a three-dimensional non invasive assessment.

The objective of this study was to supply quantitative information about the facial soft-tissues of a group of patients with hypohidrotic ectodermal dysplasia. The three-dimensional coordinates of 28 soft-tissue facial landmarks were obtained by an electromagnetic digitizer in 11 male and 9 female patients with hypohidrotic ectodermal dysplasia aged 7-41 years, and in 318 healthy individuals of the same age, ethnicity, and sex. From the landmarks, facial areas (eyes, ears, nose, and lips) and volumes (nose and lips) were calculated according to a geometrical model of face. Data were compared to those collected in the normal subjects by computing z-scores. Male and female z-scores were not significantly different. In the pooled sample, the deviations from the norm were particularly evident in the lips, with a significant (Student's t-test, P < 0.05) increment of the total lip area (mean z-score: 0.96) and of the vermilion area of the upper lip (mean z-score: 1.07), a finding negatively related (r = -0.632) to the number of teeth present in the mouth. The eye area was reduced in most patients, a finding significant on the left side (mean z-score: -0.76). Most of the facial areas and volumes of the ectodermal dysplasia patients had z-scores deviating only +/-2 standard deviations from the reference groups. Only 4% of measurements had z-scores larger than +/-3. Additionally, a large inter-individual variability was found, together with a certain age-related trend of improvement of the number of measurements within the +/-2 interval. The method allowed a simple, low cost, fast, and non invasive examination of the patients, and provided a quantitative assessment of the deviation from the norm.

Soft tissue facial morphology in obese adolescents: a three-dimensional noninvasive assessment.

The number of obese adolescents is increasing in the Western society. For a deeper understanding of the mechanisms underlying this pathology, the quantitative characteristics of the facial soft tissues should also be investigated. The three-dimensional coordinates of 12 soft tissue facial landmarks were obtained by computerized digitizers in 11 male and 14 female adolescents aged 13-17 years, all with a body mass index larger than 30 kg/m2 (mean 31.67 kg/m2, SD 1.58). From the landmarks, several facial dimensions were calculated. Data were compared with those collected in normal individuals of the same age, ethnicity, and sex by computing z scores. Significant (paired Student's t-test, P < .05) larger dimensions were found for skull base width (girls), mandibular width (both sexes), lower face depth (girls), and mandibular corpus length (girls). In the pooled sample (boys plus girls), the faces of obese adolescents were significantly wider transversally (skull base width, mandibular width), deeper sagittally (mid and lower face depth, mandibular corpus length), and shorter vertically (upper facial height) than those of their normal school companions. "Borderline" obese adolescents possessed some facial characteristics typical of patients with more substantial obesity. The effect of an increased body weight-per-height was therefore present also in subjects not already referred to a medical control.

A quantitative three-dimensional assessment of soft tissue facial asymmetry of cleft lip and palate adult patients.

The three-dimensional coordinates of 23 selected soft-tissue facial landmarks were digitized on 18 cleft lip and palate (CLP) white patients (11 male and 7 female patients aged 19-27 years) and 161 healthy controls (73 female and 89 male subjects aged 18-30 years) by an electromagnetic instrument. Facial asymmetry was quantified by detecting a plane of symmetry and the centers of gravity (CG) of the right and left hemifaces and by calculating the distance between the two CG (distance from symmetry [DFS]). Both absolute (millimeters) and percentage (of the nasion center of gravity distance) DFS was obtained. The asymmetry of single landmarks was also quantified. Overall, asymmetry in operated CLP patients appeared only moderately larger than that measured in the healthy reference population, with the largest value being only 5% larger than the maximum normal asymmetry. Female patients had a somewhat larger lateral asymmetry than male patients, and unilateral CLP patients (particularly the men) were more asymmetrical than bilateral CLP patients. Pronasale and subnasale landmarks were asymmetrical in 8 patients, whereas endocanthion, zygion, cheilion, and gonion landmarks were symmetrical in all patients. In conclusion, the facial soft-tissue structures of CLP patients operated on as adults were only moderately more asymmetrical than those measured in a reference group of the same age, sex, and ethnicity.

A quantitative three-dimensional assessment of abnormal variations in facial soft tissues of adult patients with cleft lip and palate.

OBJECTIVE: To supply quantitative information about the facial soft tissues of adult operated patients with cleft lip and palate (CLP). DESIGN, SETTING, AND PATIENTS: The three-dimensional coordinates of soft tissue facial landmarks were obtained using an electromagnetic digitizer in 18 Caucasian patients with CLP (11 males and 7 females aged 19 to 27 years) and 162 healthy controls (73 females and 89 males aged 18 to 30 years). From the landmarks, 15 facial dimensions and two angles were calculated. Data were compared with those collected in healthy individuals by computing z-scores. Two summary anthropometric measurements for quantifying craniofacial variations were assessed in both the patients and reference subjects: the mean z-score (an index of overall facial size), and its SD, called the craniofacial variability index (an index of facial harmony). RESULTS: In treated patients with CLP, facial size was somewhat smaller than in normal individuals, but in all occasions the mean z-score fell inside the normal interval (mean +/- 2 SD). Almost all patients had a craniofacial variability index larger than the normal interval, indicating a global disharmonious appearance. Overall, in patients pronasale, subnasale, and pogonion were more posterior, the nose was shorter and larger, the face was narrower, and the soft tissue profile and upper lip were flatter than in the reference population. CONCLUSIONS: The facial soft tissue structures of adult operated patients with CLP differed from those of normal controls of the same age, sex, and ethnic group. In this patient group, surgical corrections of CLP failed to provide a completely harmonious appearance, even if the deviations from the reference were limited. Further analyses of larger groups of patients are needed.

Three-dimensional assessment of the reliability of a postural face-bow transfer.

STATEMENT OF PROBLEM: Incorrect 3-dimensional orientation of a dental cast may compromise the functional and esthetic result of prosthetic restorations. PURPOSE: This study assessed the reliability of a new method to transfer the 3-dimensional orientation of the occlusal plane with a postural face-bow. MATERIAL AND METHODS: The 3-dimensional position of the occlusal plane in 20 subjects (age 20 to 32 years) with a complete dentition in both arches was assessed with a postural face-bow. An irreversible hydrocolloid impression of the maxillary arch was made for each subject and poured in dental stone. The maxillary arch was mounted in an articulator with use of a postural face-bow. The 3-dimensional position of the occlusal plane was then measured and compared to the values obtained with the use of a previously certified, computerized, noninvasive instrument. This instrument digitizes the coordinates of dental and facial landmarks and then calculates the spatial position of the occlusal plane. For each subject, the direct assessment and the face-bow measurement were compared by calculating the absolute difference of the following: the inclination of the occlusal plane relative to the true vertical, frontal plane projection (angle alpha) and sagittal plane projection (angle beta); intercondylar distance; distance of the center of gravity of the anterior part of the maxillary arch to the midpoint of the intercondylar axis; and the maxillary right canine to right condylion distance. Descriptive statistics of the differences were calculated. RESULTS: The postural face-bow appeared reliable and compared well to the computerized assessment, with mean differences ranging from 2.5 degrees to 3 degrees. CONCLUSION: In the population tested, a postural face-bow reliably reproduced the spatial orientation of the occlusal plane relative to the true horizontal plane. This position was transferred to an articulator with limited errors.