Surface anatomy of the face in Down's syndrome: age-related changes of anthropometric proportion indices in the craniofacial regions

The purpose of the study was to determine the age-related changes in normal and abnormal proportion indices in Down's syndrome patients between 1 to 5, 6 to 15, and 16 to 36 years of age. Nine indices were analyzed in five craniofacial regions of 125 subjects: 70.2% to 79.0% were normal and 21.0% to 29.8% abnormal. Proportionate indices increased in frequency in all age groups in a much higher percentage than disproportionate ones. In the oldest group, the frequency of normal proportions significantly increased in the head and trended higher in the facial, orbital, and nasal regions, and lower in the ear. Disproportions showed a similar pattern, with a decreasing frequency in all regions except the ear. The variations of harmony and disharmony in normal proportions, and moderate and severe in disproportions, helped clarify the morphological changes influencing the craniofacial design. Among proportionate ratios, harmony ranged from 45% to 65.5% in age group 1 and from 30% to 87.5% in group 3. No cases of severe subnormal disproportions were seen in the nasal tip protrusion-nose width and nasal root depth indices in age group 1, and none in the cephalic index, midface-lower face depth, and nasal tip protrusion-nose width indices in group 3. The 20-year age range of group 3 helped show the post-maturation improvements of the face and the remedying effect of the extended growth rate on some initial facial disproportions.     

Surface anatomy of the face in Down's syndrome: linear and angular measurements in the craniofacial regions

Measurements (23 projective linear, 2 angular) taken in the 6 craniofacial regions of 127 patients with Down's syndrome showed that 63.1% (1,836 of 2,908) were within normal limits and 36.9% (1,072) were outside them. Abnormal measurements were subnormal in 90.8% (973) and supernormal in 9.2% (99). All statistical summaries were based on z scores (adjusting for age and sex differences) classified into a small number of ranges to yield a simplified frequency distribution for each measurement. The purpose of the study was to identify the measurements closest to normal and those indicating the most severe degrees of sub- or supernormality. Approximately a quarter of normal measurements were classified as optimal, and half the subnormal or supernormal measurements were classified as severe. Intercanthal width had the highest frequency of optimal measurements (93.7%, 119 of 127), head circumference the smallest (28.6%, 36 of 126). Knowledge of the frequency of extreme abnormalities in the craniofacial regions will help during visual examination of patients with Down's syndrome. This study found the highest percentage of severely subnormal measurements in the orbital region (57.8%, 74 of 128) and the smallest in the labio-oral region (32.7%, 16 of 49). The measurement with the highest proportion of severely subnormal to all subnormal values was the palpebral fissure length (68%, 51 of 75), and the nose width had the smallest proportion (14.3%, 1 of 7).     

Craniofacial disproportions in Apert's syndrome: an anthropometric study

Twenty craniofacial indices composed of 26 surface measurements taken directly from the head and face were determined in 14 Apert's syndrome patients 18 days to 5 years old (younger subgroup) and 14 patients ages 6 years to 15 years old (older subgroup). All of the patients were North American Caucasians who had undergone early suture release but no facial repair. The indices were compared with those in healthy controls of the same age and sex. The wide intercanthal distance in relation to the narrow soft nose was the most frequent (81.5%) and extensive (17.7% above the maximum normal index value) disproportion. Abnormal indices occurred most often with the combination of one abnormal and one normal measurement (61.0%). All seven of the 16 disproportions seen in both age subgroups increased in frequency nonsignificantly with age: the supernormal cephalic, intercanthal, nasal, and vertical mandibulofacial indices and the subnormal nasofacial, upper face, and jaws' arcs indices. Of the six disproportions that decreased in frequency with age, four changed significantly (the supernormal frontoparietal and frontozygomatic indices and the subnormal mandibulofacial and nasozygomatic indices) and two changed nonsignificantly (the supernormal intercanthoalar and subnormal cheilozygomatic indices). With the exception of two nasal proportions, the extent of the disproportionality decreased in all of the indices that increased with age.     

Patterns of dysmorphology in Crouzon syndrome: an anthropometric study

Twenty-four craniofacial proportion indices were calculated from 26 surface measurements taken directly from the head and face in 61 patients with Crouzon syndrome, aged 11 days to 32 years. All patients were North American caucasians who had not undergone facial repair. The measurements and proportions were compared with those in healthy controls of the same age and sex. In most patients, the only disproportions present were a wide forehead in relation to the cranial breadth and wide orbital region compared with the face width. The proportions were in the normal range in most cases (71.7%), although many tended toward its extremities. Disproportions were associated most frequently with a combination of abnormal and normal measurements (48.9%); however, a large number (42.4%) involved two normal measurements. Among the normal proportions, most involved two normal measurements, although almost one fourth (22.8%) were associated with one or two abnormal measurements.     

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.     

Proportion indices in the craniofacial regions of 284 healthy North American white children between 1 and 5 years of age

The study's aim was to provide the normal range data on 81 anthropometric proportion indices of the craniofacial complex, separately in boys and girls between 1 and 5 years of age, supplementary to the previously published normal proportion values of the North American white population from 6 to 18 years of age. In the first age group, 17 or 18 boys and 18 or 22 girls were measured. In each age group between 2 and 5 years old, 30 boys and 30 or 31 girls were examined. The normal values of the 81 proportion indices were established with the help of 45 measurements (7 cranial, 13 facial, 4 orbital, 12 nasal, 7 labio-oral, and 2 auricular) taken from 287 healthy children. The data on the normal indices were reported in two groups: areal and interareal. The areal proportions are formed by taking measurements from one particular craniofacial region. Proportions indicating the quality of relation of measurements taken from two craniofacial regions were classified as interareal (N = 36). The basic proportions (N = 13) of the areal one show the relation between the measurements influencing the general view of each craniofacial region. The detailed analysis of the proportionality in the individual regions, carried out with the help of the other measurements within the regions, established 36 additional areal proportion indices. The recommended method of examination is to start with the basic proportions, which offers the determination of the most and least disproportionate craniofacial region, followed by a more comprehensive search for other disproportions with the help of the additional areal proportions (N = 36) and interareal proportions (N = 32).     

Anthropometric growth study of the head.

Five measurements of the head were taken between 1 year and 18 years of age in 1,537 North American Caucasians. By 1 year of age, the circumference (87.5%) and length (87.1%) of the head showed the highest levels of developmental level compared with their adult size. By 5 years, the developmental level of all measurements in head width, head length, and circumference increased, closely approaching maturation. Head length reached full maturation at 10 years in females (182.7 mm), and at 14 years in males (189.2 mm). In females, head width showed the most advanced maturation at 14 years (142.7 mm). In males, most of the head measurements matured at 15 years of age. Adult head height was approached at 13 years in both sexes (113.3 mm in males and 109.8 mm in females). Early rapid growth in head height and head length took place between 1 and 4 years of age, and between 1 and 6 years in forehead width. The head width and head circumference showed continuous but mild growth rates throughout this period.     

Salivary sialic acid, protein, salivary flow rate, pH, buffering capacity and caries indices in subjects with Down's syndrome

OBJECTIVES: The aim of this study was to compare salivary sialic acid, protein, salivary flow rate, pH and buffering capacity and caries indices between subjects with Down's Syndrome and healthy controls. METHODS: Unstimulated mixed saliva was collected from 26 Down's syndrome subjects and 25 healthy subjects of age range 6-24 years. Total protein was determined by the method of Lowry and total sialic acid using Ehrlich reagent. Laemmli SDS-polyacrylamide gel electrophoresis was also carried out. RESULTS: Buffering capacity and pH were quite similar for both groups. For permanent dentition subjects pH was significantly higher (P = 0.03) in the Down's syndrome group. The salivary flow rate of the Down's syndrome subjects was significantly lower (P < 0.01) than that of healthy controls and the Down's syndrome subjects' salivary protein and sialic acid levels were significantly higher (P < 0.001). The ratios of total sialic acid to total protein were significantly higher (P < 0.001) in the Down's syndrome group. However, salivary sialic acid expectoration rates, a means of compensating for flow rate differences, were significantly lower (P = 0.01) in the Down's syndrome subjects than in controls. Electrophoresis revealed no significant differences between the protein bands of the groups. There were no significant differences in caries indices between groups, even when compensated for age, nor in the salivary parameters within groups between sexes. CONCLUSIONS: Total salivary sialic acid in Down's syndrome subjects, higher in terms of levels but lower in terms of expectoration rates, was significantly different from that of controls of similar caries indices.     

A quantitative study of the face in Down's syndrome.

The large number of persons with Down's syndrome among the group of physically and mentally retarded demands that continuing study be directed toward its causes and effects. Much conflicting data are reported in the literature concerning the facial and cranial effects of this syndrome. The cephalic proportions, in profile, of a group of male Caucasian trisomic Mongoloids were compared with the proportions of a control group of male Caucasians of similar age range. Using the areas of the midface, mandible, and endocranium obtained from cephlograms of the two groups, the following ratios were studied: (1) midfacial area/endocranial area (2) mandibular area/endocranial area, and (3) midfacial area/mandibular area. A significant degree of deficiency in midfacial area, mandibular area, and endocranial area was found in the Mongoloid group. In studying the facial proportions, we found that the Down's syndrome group's ratios were significantly smaller in all three areas. The magnitude of the deficiency in the Mongoloid midface, both in gross area and in relation to endocranial area, remained nearly constant with age. The ratio of midfacial area to mandibular area in Mongoloids was much more comparable to that of the normal group than the other two ratios studied. In both groups the ratio of the midfacial area to the mandibular area became smaller with age. The decrease was more rapid in the Down's syndrome group. The findings of this study imply that all areas of the face and skull are deficient in persons with Down's syndrome. The data point to the possibility that the characteristics of this syndrome and the deficiencies described are polygenic in origin. Also, contrary to the majority of reports in the literature, the mandible and the midface grow in approximately the same proportion in both study and control groups     

Soft tissue facial angles in Down's syndrome subjects: a three-dimensional non-invasive study

The aim of the present study was to obtain quantitative information concerning the three-dimensional (3D) arrangement of the facial soft tissues of subjects with Down's syndrome. The 3D co-ordinates of 50 soft tissue facial landmarks were recorded by an electromechanical digitizer in 17 male and 11 female subjects with Down's syndrome aged 12-45 years, and in 429 healthy individuals of the same age, ethnicity and gender. From the landmark co-ordinates, geometric calculations were obtained of several 3D facial angles: facial convexity in the horizontal plane (upper facial convexity, mid facial convexity including the nose, and lower facial convexity), mandibular corpus convexity in the horizontal plane, facial convexity including the nose, facial convexity excluding the nose, interlabial angle, nasolabial angle, angle of nasal convexity, left and right soft tissue gonial angles. Data were compared with that collected for the normal subjects by computing the z-scores.Facial convexity in the horizontal plane (both in the upper and mid facial third), facial convexity in the sagittal plane and the angle of nasal convexity were significantly (P < 0.05) increased (flatter) in subjects with Down's syndrome than in the normal controls. Both left and right soft tissue gonial angles were significantly reduced (more acute) in the Down's syndrome subjects. Subjects with Down's syndrome had a more hypoplastic facial middle third with reduced nasal protrusion, and a reduced lower facial third (mandible) than reference, normal subjects.     

Dental and alveolar arch widths in normal occlusion, class II division 1 and class II division 2

The aim of this study was to compare the transverse dimensions of the dental arches and alveolar arches in the canine, premolar, and molar regions of Class II division 1 and Class II division 2 malocclusion groups with normal occlusion subjects. This study was performed using measurements on dental casts of 150 normal occlusion (mean age: 21.6 +/- 2.6 years), 106 Class II division 1 (mean age: 17.2 +/- 2.4 years), and 108 Class II division 2 (mean age: 18.5 +/- 2.9 years) malocclusion subjects. Independent-samples t-test was applied for comparisons of the groups. These findings indicate that the maxillary interpremolar width, maxillary canine, premolar and molar alveolar widths, and mandibular premolar and molar alveolar widths were significantly narrower in subjects with Class II division 1 malocclusion than in the normal occlusion sample. The maxillary interpremolar width, canine and premolar alveolar widths, and all mandibular alveolar widths were significantly narrower in the Class II division 2 group than in the normal occlusion sample. The mandibular intercanine and interpremolar widths were narrower and the maxillary intermolar width measurement was larger in the Class II division 2 subjects when compared with the Class II division 1 subjects. Maxillary molar teeth in subjects with Class II division 1 malocclusions tend to incline to the buccal to compensate the insufficient alveolar base. For that reason, rapid maxillary expansion rather than slow expansion may be considered before or during the treatment of Class II division 1 patients.     

Effect of periodic preventive care on the progression of periodontal disease in young adults with Down's syndrome

OBJECTIVES: To examine the effect of periodic preventive care on the progression of periodontal disease in 24 young adults with Down's syndrome (DS) (mean age+/-SD: 20.8+/-5.6 years) MATERIAL AND METHODS: Subjects were divided into two groups: 13 subjects who had frequently visited our clinic (mean interval between visits: 3.7+/-1.3 months; managed group) and 11 subjects who had not visited our clinic for more than 1 year (mean duration of no visits: 27.5+/-10.1 months; interrupted group). The progression of periodontal disease in the subjects was evaluated clinically, microbiologically and roentgenologically. RESULTS: Clinical parameters (probing depth, frequency of the presence of a pathological periodontal pocket, alveolar bone loss, frequency of the incidence of pathological bone loss, and modified total PMA (M-PMA)) and benzoyl-DL-arginine-naphthylamide (BANA) scores in the interrupted group were significantly higher than those in the managed group. Subject age showed significant positive correlations with probing depth and alveolar bone loss. BANA scores showed significant positive correlations with probing depth, alveolar bone loss and M-PMA in the interrupted group. CONCLUSIONS: The results suggest that periodic preventive care is effective for suppressing the progression of periodontal disease in young adults with DS.     

Craniocervical postural relations and craniofacial morphology in 30 blind subjects

Previous studies have shown that head posture is dependent on vision. The head posture of blind persons therefore can be expected to differ from that of normal subjects. This is of interest in the current analyses of the relation between head posture and craniofacial morphology. The purpose of the present investigation was to describe the posture of the head and cervical column and the craniofacial morphology in a group of blind subjects, and to compare the findings with those previously found in male and female groups of normal subjects. The sample comprised 30 blind subjects--18 men and 12 women, aged 15 to 35 years, all of whom had been without perception of light since birth. The control group comprised 120 male dental students in the age range 22 to 30 years and 51 female dental students in the age range 22 to 27 years. The analysis of head posture showed that the intra-and interindividual variabilities of the craniovertical angles were significantly larger than those of the craniocervical angles in the blind group. The interindividual variabilities of the craniovertical angles were significantly larger in the blind than in the control group, but the variabilities of the craniocervical angles were similar in both groups. Craniovertical relations thus were more variable in the blind subjects, whereas craniocervical relations showed the same variability as normal subjects. On the average, the head was carried in a 4.3 degrees lower position in the neck was 4.5 degrees more forward inclined in the blind group. No differences were found in the position of the head in relation to the cervical column between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dental and alveolar arch widths in normal occlusion and Class III malocclusion

The aim of this study was to compare the transverse dimensions of the dental arches and alveolar widths of Class III malocclusion group with a group of untreated normal occlusion subjects. This study was performed using measurements on dental casts of 150 normal occlusion (mean age, 21.6 +/- 2.6 years) and 100 Class III malocclusion (mean age, 15.4 +/- 2.2 years) subjects. Independent samples t-test was applied for comparing the groups. The findings of this study indicated that the mandibular intercanine and intermolar alveolar widths were significantly larger in the Class Ill group when compared with the normal occlusion sample (P < .001). Maxillary interpremolar, intermolar widths and all maxillary alveolar width measurements were significantly narrower in the Class III group (P < .001). In addition, the lower canine and premolar alveolar width measurements were also statistically significantly larger in the normal occlusion group when compared with the Class III malocclusion group (P < .001). Subjects with Class III malocclusion tend to have the maxillary teeth inclined to the lingual and mandibular teeth inclined to the buccal direction because of the restriction of maxillary growth and development according to dental arch width measurements. Therefore, rapid maxillary expansion should be considered before or during the treatment of a Class III patient with or without face-mask therapy.     

International anthropometric study of facial morphology in various ethnic groups/races

When anthropometric methods were introduced into clinical practice to quantify changes in the craniofacial framework, features distinguishing various races/ethnic groups were discovered. To treat congenital or post-traumatic facial disfigurements in members of these groups successfully, surgeons require access to craniofacial databases based on accurate anthropometric measurements. Normative data of facial measurements are indispensable to precise determination of the degree of deviations from the normal. The set of anthropometric measurements of the face in the population studied was gathered by an international team of scientists. Investigators in the country of the given ethnic group, experienced and/or specially trained in anthropometric methods, carried out the measurements. The normal range in each resultant database was then established, providing valuable information about major facial characteristics. Comparison of the ethnic groups' databases with the established norms of the North America whites (NAW) offered the most suitable way to select a method for successful treatment. The study group consisted of 1470 healthy subjects (18 to 30 years), 750 males and 720 females. The largest group (780 subjects, 53.1%) came from Europe, all of them Caucasians. Three were drawn from the Middle-East (180 subjects, 12.2%), five from Asia (300 subjects, 20.4%) and four from peoples of African origin (210 subjects, 14.3%). Their morphological characteristics were determined by 14 anthropometric measurements, 10 of them used already by classic facial artists, Leonardo da Vinci and Albrecht Dürer, complemented by four measurements from the nasal, labio-oral and ear regions. In the regions with single measurements, identical values to NAW in forehead height, mouth width, and ear height were found in 99.7% in both sexes, while in those with multiple measurements, vertical measurements revealed a higher frequency of identical values than horizontal ones. The orbital regions exhibited the greatest variations in identical and contrasting measurements in comparison to NAW. Nose heights and widths contrasted sharply: in relation to NAW the nose was very or extremely significantly wide in both sexes of Asian and Black ethnic groups. Among Caucasians, nose height significantly differed from NAW in three ethnic groups, with one shorter and two greater. In the Middle Eastern groups nose width was identical to those of NAW but the height was significantly greater. The present study, conducted by investigators working separately across the world and with small samples of the population, is clearly preliminary in nature and extent. Yet it may fulfill its mission if medical and anthropological investigators continue the work of establishing normative data of the face. These data are urgently needed by medical professionals but have been lacking up till now in western and northern Europe, Asia, and Africa.     

Cervical column morphology related to head posture, cranial base angle, and condylar malformation

The present study describes the cervical column as related to head posture, cranial base, and mandibular condylar hypoplasia. Two groups were included in the study. The 'normal' sample comprised 21 subjects, 15 females aged 23-40 years (mean 29.2 years), and six males aged 25-44 years (mean 32.8 years) with neutral occlusion and normal craniofacial morphology. The condylar hypoplasia group comprised the lateral profile radiographs of 11 patients, eight females, and three males, aged 12-38 years (mean 21.6 years). For each individual, a profile radiograph was taken to perform a visual assessment of the morphology of the cervical column. For the normal group only, the profile radiographs were taken in the standardized head posture to measure the head posture and the cranial base angle. Cervical column: Morphological deviations of the cervical column occurred significantly more often in the subjects with condylar hypoplasia compared with the normal group (P < 0.05 and P < 0.01, respectively). The pattern of morphological deviations was significantly more severe in the subjects with condylar hypoplasia compared with the normal group (P < 0.01). Cervical column related to head posture and cranial base: The cervicohorizontal and cranial base angles were statistically larger in females than in males (P < 0.05 and P < 0.01, respectively). No statistically significant age differences were found. Only in females was the cervical lordosis angle (OPT/CVT, P < 0.01), the inclination of the upper cervical spine (OPT/HOR, P < 0.05), and the cranial base angle (n-s-ba, P < 0.05) significantly positively correlated with fusion of the cervical column. These associations were not due to the effect of age.     

Anthropometric finding in Nigerian children with sickle cell disease

PURPOSE: Sickle cell disease (SCD) subjects have been widely reported to present with various anthropometric deficits, including malocclusion and stunting, compared to their unaffected peers. This study was carried out to examine these reports in Lagos. METHODS: A hospital-based cross-sectional study was carried out in 3 outpatient SCD units of one teaching and two general hospitals. All established SCD subjects aged 1 to 18 years (n = 177) were examined on consecutive clinic days. Controls (unaffected subjects; n = 122) were obtained from well-baby and surgical emergency clinics. Facial profile, occlusion, height, weight, head and mid-upper arm (MUA) circumference measurements were noted. RESULTS: A prognathic maxillary profile was found to be more prevalent in SCD subjects (21%) than controls (4%; P < .05). Class II malocclusion was found in 21% of SCD subjects compared to 2% of controls (P < .05). The overall mean height, weight and head circumference of SCD subjects and controls were not significantly different (P > .05). However, at age 18 years, the weight of the SCD group was significantly less than that of the control group (P < .05).The mean MUA circumference was significantly higher in the control group (20.04 cm +/- 3.80) than in SCD subjects (17.91 cm +/- 2.96; P < .05). CONCLUSIONS: There was a higher prevalence of maxillary protrusion. and Class II malocclusion in SCD subjects than controls. Height and weight were not significantly different in both groups except at 18 years when SCD subjects weighed less than controls.     

Mandibular third molar eruption in relation to available space as assessed on lateral cephalograms

It has previously been suggested that the distance between the Xi point (Ricketts 1972) and the distal aspect of the mandibular second molar (M2), measured on lateral cephalometric head films, should be at least 25 mm by adulthood to allow for the normal eruption of the third molars (M3s) in the lower jaw. It was the aim of this investigation to test the validity of this statement in two groups of young adults (mean age 25 years). The individuals in the first group had complete dentitions including M3s in good occlusions. In the second group all M3s had been extracted due to failure to erupt. Mandibular length and morphology and the dimension of the ramus was also studied in the same material. All measurements were made on standard lateral head films. The distance Xi-M2 was found to be significantly greater in individuals with complete dentitions as compared with individuals who had impacted M3s. Furthermore, this variable exhibited significantly greater values in males than in females in both investigation groups. However, in nearly fifty per cent of the subjects with complete dentitions, the M3s had erupted despite a Xi-M2 distance of less than 25 mm. Mandibular length in males was significantly greater in the complete group than in the extraction group. In females no such difference was recorded. The angular measurements used in this study did not differ significantly between the complete and the extraction groups.     

Age and gender differences in temporomandibular joint radiographic findings before orthodontic treatment in adolescents

OBJECTIVE: The purpose of this study was to determine whether there is a relationship between abnormal temporomandibular joint radiographic findings and age or gender in a sample of young preorthodontic patients. STUDY DESIGN: A total of 491 consecutive patients, aged 9 to 15 years, were referred for orthodontic records. Routine preorthodontic radiographs, including corrected sagittal tomographs, were taken for each patient and viewed by an observer blinded to clinical records. Temporomandibular joint radiographic findings were classified as normal or abnormal. For comparative purposes, the study population was divided into 2 age groups (9-11 years and 12-15 years). RESULTS: Frequency of abnormal findings ranged from 2.4% to 11.5% and was similar for both sides. Temporal component abnormalities correlated with abnormalities of condylar position, joint space, and condylar osseous morphology. The frequency of osseous abnormalities was higher in girls and highest in older girls. CONCLUSIONS: There are significant differences between genders for some temporomandibular joint radiographic abnormalities, and in our study sample the frequency of abnormalities was highest in 12-to-15-year-old girls.