Influence of cranial deformation on facial morphology among prehistoric South Central Andean populations

Calculating biodistances among South American populations using cranial measurements is often hindered, as many available skeletal collections exhibit deformation. Acknowledging vault modifications, researchers have sought measurements in other regions which are unaffected by deformation. In the 1970s, a set of 10 "relatively" unaffected facial measurements was identified in Argentinean crania that later became the basis of numerous South American biodistance studies. These measurements include: minimum frontal breadth, bizygomatic breadth, orbit height, orbit breadth, palate breath, palate length, upper facial height, basion-prosthion length, nasal height, and nasal breadth. Palate length was excluded from the present analysis due to considerable measurement error. The suitability of these measurements in populations other than Argentineans has not been rigorously tested. Using a sample of 350 prehistoric crania from the Museo Arqueológico San Miguel de Azapa (MASMA, Arica, Chile), this project tested the hypothesis that these measurements are unaffected by either annular or tabular deformation. Results obtained from MANOVA analysis indicate this hypothesis cannot be fully supported. Among males, only 3 of the 9 measurements are unaffected by either form of deformation (palate breadth, basion-prosthion length, and nasal breadth), while analysis of females indicates that 4 of the 9 measurements remain unaltered (minimum frontal breadth, orbit breadth, basion-prosthion length, and nasal breadth). Additionally, analogous to the vault, facial measurements display patterns consistent with the deformation applied. Two implications can be drawn from this research: 1) previous studies using these measurements must be interpreted cautiously, and 2) researchers using these measurements must explicitly test their suitability in each population.     

Internal nasal floor configuration in Homo with special reference to the evolution of Neandertal facial form

The presence of a steeply sloping or depressed nasal floor within the nasal cavity of Neandertals is frequently mentioned as a likely specialization or autapomorphy. The depressed nasal floor has also been seen as contributing to a relatively more capacious nasal cavity in Neandertals, which is tied to cold-climate respiratory adaptation and energetics. These observations have been limited largely to a relatively few intact crania, and the character states associated with this trait have not been as precisely codified or analyzed as those published for Plio-Pleistocene hominins (McCollum et al., 1993, J. Hum. Evol. 24, 87; McCollum, 2000, Am. J. Phys. Anthrop. 112, 275).This study examines the internal nasal floor topography in complete crania and isolated maxillae in European, west Asian, and African fossil Homo (n=158) including 25 Neandertals, and a wide range of recent humans from Europe, the Near East, and Africa (n=522). The configuration of the internal nasal floor relative to the nasal cavity entrance is codified as: 1) level, forming a smooth continuous plane; 2) sloped or mildly stepped; or 3) bilevel with a pronounced vertical depression. The frequency of these nasal floor configurations, and their relationship to both nasal margin cresting patterning and a comprehensive set of nasofacial metrics is examined.Neandertals show a high frequency of the bilevel (depressed) configuration in both adults and subadults (80%), but this configuration is also present in lower frequencies in Middle Pleistocene African, Late Pleistocene non-Neandertal (Skhul, Qafzeh), and European Later Upper Paleolithic samples (15%-50%). The bilevel configuration is also present in lower frequencies (ca. 10%) in all recent human samples, but attains nearly 20% in some sub-Saharan African samples. Across extinct and extant Homo (excluding Neandertals), internal nasal floor configuration is not associated with piriform aperture nasal margin patterning, but the two are strongly linked in Neandertals. Variation in internal nasal floor configuration in recent humans is primarily associated with internal nasal fossa breadth and nasal bridge elevation, whereas in fossil hominins, it is associated primarily with variation in facial height. Cold-climate and activity-related thermal adaptation as an explanation for the high frequency of pronounced nasal floor depression in Neandertals is inconsistent with all available data. Alternatively, variation in internal nasal floor configuration is more likely related to stochastically derived populational differences in fetal nasofacial growth patterns that do not sharply differentiate genus Homo taxa (i.e., cladistically), but do phenetically differentiate groups, in particular the Neandertals, especially when considered in combination with other nasofacial features.     

Growth status of children treated for unilateral cleft lip and palate

Cephalometric distances, angles, and proportions were evaluated for 32 children 5 to 8 years of age treated for unilateral cleft lip and palate. The children were age and sex matched with untreated controls with normal skeletal relationships. The unilateral cleft lip and palate sample was treated by the same surgeon and orthodontist using the same techniques and appliances. Measures of overall facial proportions, facial convexity, and prognathism were not significantly different between the two groups. The primary group differences pertain to the posterior aspect of the maxilla, which is vertically short in the unilateral cleft lip and palate sample. Horizontally, the maxilla of the unilateral cleft lip and palate children was significantly longer, producing a steeper palatal plane. In addition, the zygoma and orbits of unilateral cleft lip and palate children were somewhat retruded; the posterior cranial base and total mandibular length also were longer in the unilateral cleft lip and palate children.     

Mechanical and spatial determinants of Paranthropus facial form

It is well documented in the anthropological literature that the distinctive morphology of the “robust” hominid facial skeleton reflects its dietary specialization. Rak (1983) has provided the most comprehensive evaluation of Paranthropus facial morphology and this important study concluded that bone strain generated during mastication was responsible for the scaling of measures of facial height and breadth. The present study evaluated Rak's analysis by examining the relationship between bizygomatic breadth and facial height in an ontogenetic series of Pan and Gorilla crania. Results of this analysis indicate that facial height and breadth dimensions were not mechanically scaled in the “robust” australopithecines. Structural analysis of African ape facial maturation was also used to examine alternative spatial methods of malar elongation in Paranthropus. It is concluded that the increased height of the malar region in these specimens is not related to either vertical expansion of the posterior facial skeleton or to expansion of the temporal fossa. Malar elongation is, however, consistent with a derived pattern of facial growth in crania possessing a thickened hard palate. © 1994 Wiley-Liss, Inc.     

A new reconstruction of the Le Moustier 1 skull and investigation of internal structures using 3-D-μCT data

Using the non-destructive technique of 3-D micro computed tomography (3-D-μCT), we present a new, virtual reconstruction of the Le Moustier 1 Neandertal skull. This new reconstruction corrects defects found in earlier reconstruction attempts by repositioning misaligned cranial fragments, addressing the problem of asymmetry caused by pressure during the fossilization process, and placing the basioccipital in its proper anatomical position. Metric comparisons between Le Moustier 1 and juvenile and adult Neandertals demonstrate that facial height proceeded at a faster rate of growth than facial prognathism at the beginning of the adolescent period. They also confirm the anterior placement of the basioccipital. A compound painted to match the colour of the fossilized bone was used in previous reconstruction attempts and the aim of this analysis was to remove the false material to reveal to what extent the fossilized bone was preserved. The areas with the most artificial material and glue include the palate, areas around the mandibular teeth, the left frontal, and parts of the right parietal and temporal bones. The μCT data were also used to examine internal structures of the skull including the frontal sinus and the labyrinth of the inner ear. An investigation of the frontal sinus reveals morphology similar to that found in adult Neandertals, although the structure does not extend to mid-orbit. The dimension of the radius of curvature of the lateral semicircular canal falls within one standard deviation, and the anterior and posterior canals within two standard deviations, of the published Neandertal mean. As in other Neandertals, the posterior semicircular canal is in an inferior position relative to the plane of the lateral canal.     

Palatal growth in baboons (Papio cynocephalus anubis)

In this study the structure and development of the palate as observed in a cross-sectional collection of olive baboons (Papio cynocephalus anubis) skulls are described and analyzed using craniometric techniques. Considered are structural functional relationships among different parts of the palate, and between the palate and other parts of the craniofacial skeleton. Several inferences are drawn and speculated upon. These inferences are as follows: odontogenesis affects premaxillary growth the most during late fetal and early postnatal development; maxillary length is significantly affected by development and eruption of the maxillary dentition, whereas maxillary breadth is less affected by dental development. Growth of the palatine bones and nasopharyngeal airway is correlated with dentomasticatory changes; the developmental and functional significance of these correlations is unclear. Further inferences are that growth rates for each palatal component differ for each sex even though lengths of the components relative to total palatal dimensions show no sexual dimorphism. Also, it is determined that maxillary length remains constant, premaxillary length reduces and palatine length increases relative to total palatal length with growth.     

Palatal dimensions in 45,X-females

Seventy-two females with 45,X-chromosome complement were examined for palatal dimensions, and the results of the measurements were compared to those of first-degree normal female relatives of the study subjects and population control females. Hard stone casts were prepared for measuring widths and lengths of the maxillary alveolar arch and palatal height between or at the level of the permanent canines, first and second premolars, and first molars with a palatometer and sharp-pointed vernier calipers (0.5 mm). According to the analyses of covariance (history of orthodontic treatment and loss of permanent teeth as cofactors and age as covariate), the differences in palatal dimensions between the groups were statistically significant or highly significant for all dimensions except for palatal height in the posterior segments. The group of the 45,X-females had the highest mean value for palatal height at the level of the canines and systematically the lowest mean values for palatal width in all segments, while no clear difference could be found in the length of the alveolar arch between the 45,X-females and the relatives, the population control group showing the lowest value in the posterior segments. The findings of this study indicate that the narrowed palate rather than the high palate is a frequent but not definite feature in 45,X-females. This may reflect the effect of sex-chromosomes on width but not other dimensions of the palate, resulting in deficiency of transversal growth of the palate possibly through decreased growth of the palatal shelves or through disturbances in the growth of the nasal septum, sutural growth, or--to which the exostosis on the palatal alveolar plates would refer--disturbances in apposition-resorption growth changes of the maxilla.     

Family resemblance for cranio-facial measurements in Velanti Brahmins from Andhra Pradesh, India

Maximum likelihood estimates of familial correlations are presented for 12 cranio-facial measurements taken on 399 nuclear families from Southern India. Marital resemblance is significantly different from zero for head circumference, head breadth, minimum frontal breadth, bizygomatic breadth, total facial height, and nasal height, but not for bigonial breadth, nose breadth, nose depth, or ear dimensions. All other familial correlations are significantly greater than zero except for the father-daughter correlation for nasal depth. Path analysis with a TAU transmission model with sex effects reveals that family resemblance for head circumference, head length, bigonial breadth, total facial height, and nasal height, but not for bigonial breadth, nose breadth, nose depth, or ear dimensions. All other familial correlations are significantly greater than zero except for the father-daughter correlation for nasal depth. Path analysis with a TAU transmission model with sex effects breadth, and sex effects in transmission were found for head breadth and nose dimensions. Sex effects in this sample may be due to the fact that different anthropometrists were used for male and female subjects.     

Premaxillary-maxillary suture fusion and anterior nasal tubercle morphology in the chimpanzee

The anterior nasal spine (ANS) is considered by some to be a unique characteristic of modern humans; however, it has been reported to occur in chimpanzees. Among human populations, ANS size correlates with facial prognathism and timing of premaxillary-maxillary sutural fusion, which may have implications for models of midfacial growth. To investigate these questions, skulls from 55 chimpanzees (Pan troglodytes) (29 male, 26 female), ranging in age from infants to adults, were examined. None of the 55 specimens examined had a true ANS, but a number of specimens exhibited raised anterior nasal prominences or tubercles (ANT) on the nasal surface of the premaxilla. Female specimens had significantly (P less than .05) more ANTs and more extensive fusion of both the palatal and facial components of the suture than did the male specimens. Results from the present study document the presence of an ANT in a sample of chimpanzee crania and are consonant with associations predicted by a septal-traction model of midfacial growth.     

Craniofacial variation in Australasian and Pacific populations

Stepwise discriminant function analysis and Mahalanobis's generalized distance are applied to 36 measurements recorded in crania from Australasia and Oceania for assessing biological relationships and possible origins of these populations. Craniofacial variation in Australia is found to be clinal. There is extreme diversity in the Murray River Valley and southern Queensland cranial series. Multiple origins of the Australians are not supported by these results. Although selection and other processes cannot be completely ruled out, gene flow and restrictions to the exchange of genes can explain most of the morphological patterning observed. Breadth and length dimensions of the vault, interorbital breadth, biorbital breadth, palate length, and upper facial height are among the most important discriminators. Viewed within the broader context of Asia and the Pacific, Australians represent a biologically distinct population, one sharing ancestral ties with Melanesians but not with the recent populations of Asia and the rest of the Pacific. The latter represent a second major population complex.     

人体测量指标与掌指纹特征之间的相关研究

本文对106名中国东北汉族女性进行了活体测量,并拓取了掌指纹。样本的年龄范围为18—34岁。所分析的人体测量指标共41项,掌指纹指标共59项。将人体测量指标与掌指纹指标同时输入电子计算机,进行了100项实验指标间的相关分析,并做了相关显著性检验。在41项人体测量指标中,有35项指标与掌指纹特征有相关关系。其中与掌指纹特征同时相关的人体测量特征有18项,与指纹特征相关的人体测量指标有2项,与掌纹相关的人体测量指标有15项。与掌指纹特征同时相关的人体测量特征,与遗传因素之间的相互关系大于与指纹相关的人体测量特征。与指纹相关的人体测量特征,与遗传因素的关系,要大于与掌纹相关的人体测量特征。     

Augmented BMPRIA-Mediated BMP Signaling in Cranial Neural Crest Lineage Leads to Cleft Palate Formation and Delayed Tooth Differentiation

The importance of BMP receptor Ia (BMPRIa) mediated signaling in the development of craniofacial organs, including the tooth and palate, has been well illuminated in several mouse models of loss of function, and by its mutations associated with juvenile polyposis syndrome and facial defects in humans. In this study, we took a gain-of-function approach to further address the role of BMPR-IA-mediated signaling in the mesenchymal compartment during tooth and palate development. We generated transgenic mice expressing a constitutively active form of BmprIa (caBmprIa) in cranial neural crest (CNC) cells that contributes to the dental and palatal mesenchyme. Mice bearing enhanced BMPRIa-mediated signaling in CNC cells exhibit complete cleft palate and delayed odontogenic differentiation. We showed that the cleft palate defect in the transgenic animals is attributed to an altered cell proliferation rate in the anterior palatal mesenchyme and to the delayed palatal elevation in the posterior portion associated with ectopic cartilage formation. Despite enhanced activity of BMP signaling in the dental mesenchyme, tooth development and patterning in transgenic mice appeared normal except delayed odontogenic differentiation. These data support the hypothesis that a finely tuned level of BMPRIa-mediated signaling is essential for normal palate and tooth development.     

New reconstruction of the moroto hominoid snout and a reassessment of its affinities toAfropithecus turkanensis

Two previous reconstructions of the Moroto hominoid palate and face made during the late 1960s suffer from several errors, in particular the angle at which the facial skeleton was hafted onto the palate, and the orientation of the canines, among others. A new reconstruction is based on the discovery that there is a good contact about 1cm logn between the palatal and facial pieces, which reveals that the snout was low and elongated as inAfropithecus turkanensis. Addition of a fragment of the right orbit reveals that the interorbital region was wide as inA. turkanensis. The remaining differences between the skulls from Moroto and Kalodirr are due to five factors:−1) pathology of the Moroto right premaxilla following ante-mortem loss of the right I¹, which led to abnormal enlargement of the right half of the nasal cavity, 2) the incisive foramina of the Moroto palate are damaged, making them appear considerably larger than they were in life, 3) damage to the upper portions of the nasal aperture making it look higher than it would in life, 4) plastic deformation and crushing of the Kalodirr specimen has greatly reduced the width of the palate and has led to the cheek tooth rows converging to the rear, and 5) the slightly larger and ontogenetically older status of the Moroto individual. Resemblances between the Moroto and Kalodirr specimens far outweight the purported or real differences and it is concluded thatMorotopithecus bishopi is a junior subjective synonym ofAfropithecus turkanensis. The sites of Moroto and Kalodirr are unlikely to differ greatly in age (certainly not as much as 4 Ma).     

Morphological observations in normal primary palate and cleft lip embryos in the Kyoto collection

Normal developmental events during human primary palate formation and alterations associated with cleft lip remain poorly defined. The purpose of this study was to analyze serially sectioned human embryos to identify morphological changes during normal palatal closure and alterations associated with failure of palatal formation. Normal and cleft embryos from the histological collection at the Congenital Anomaly Research Center at the University of Kyoto were studied and photographed for detailed evaluation. Seven serially sectioned cleft lip embryos of stages shortly after primary palate formation (Streeter-O'Rahilly stages 19, 20, and 22) with unilateral or bilateral clefts with varying degrees of clefting were studied. In the normal Kyoto embryos, initial nasal fin (epithelial seam) formation was observed between the medial nasal process and the lateral nasal and maxillary processes at stage 17. During stages 18 and 19, the nasal fin epithelium was replaced by an enlarging mesenchymal bridge, as the maxillary processes united with the medial nasal processes to form the primary palate. The most prominent features observed in the cleft embryos were a reduced thickness of mesenchymal bridging between the medial nasal and maxillary processes, with an excessive amount of epithelium at the junctions between these processes. With ingrowth of the maxillary processes, greater cell dispersion and apparent extracellular matrix accumulation were observed in the medial nasal region. During closure of the primary palate, terminal branches of the maxillary nerve crossed the mesenchymal bridge to the medial nasal region. The partial clefts had reduced maxillary ingrowth and smaller union areas with the medial nasal process. Detailed studies of experimental animal models are required to identify regional growth required for contact between the facial prominences, to clarify the mechanisms of mesenchymal ingrowth and epithelial displacement during palatal formation, and to identify local and/or general factors causing alterations that lead to primary palatal clefting.     

A new reconstruction of the Le Moustier 1 skull and investigation of internal structures using 3-D-μCT data

Using the non-destructive technique of 3-D micro computed tomography (3-D-μCT), we present a new, virtual reconstruction of the Le Moustier 1 Neandertal skull. This new reconstruction corrects defects found in earlier reconstruction attempts by repositioning misaligned cranial fragments, addressing the problem of asymmetry caused by pressure during the fossilization process, and placing the basioccipital in its proper anatomical position. Metric comparisons between Le Moustier 1 and juvenile and adult Neandertals demonstrate that facial height proceeded at a faster rate of growth than facial prognathism at the beginning of the adolescent period. They also confirm the anterior placement of the basioccipital. A compound painted to match the colour of the fossilized bone was used in previous reconstruction attempts and the aim of this analysis was to remove the false material to reveal to what extent the fossilized bone was preserved. The areas with the most artificial material and glue include the palate, areas around the mandibular teeth, the left frontal, and parts of the right parietal and temporal bones. The μCT data were also used to examine internal structures of the skull including the frontal sinus and the labyrinth of the inner ear. An investigation of the frontal sinus reveals morphology similar to that found in adult Neandertals, although the structure does not extend to mid-orbit. The dimension of the radius of curvature of the lateral semicircular canal falls within one standard deviation, and the anterior and posterior canals within two standard deviations, of the published Neandertal mean. As in other Neandertals, the posterior semicircular canal is in an inferior position relative to the plane of the lateral canal.     

Australopithecine taxonomy and phylogeny in light of facial morphology

The beginning of specialization characterizing the robust australopithecines is manifested in almost every aspect of the masticatory system of Australopithecus africanus. Of particular significance is the presence of two massive bony columns on both sides of the nasal aperture that support the anterior portion of the palate. These columns--the anterior pillars--are viewed as a structural response to the greater occlusal load stemming from the beginning stages of molarization of the premolars and exerted on the more anterior part of the dental arcade. In A. africanus the molarization process is, indeed, just in its initial phase, but the still considerable protrusion of the palate relative to the more peripheral facial frame increases the need for pillars. The anterior pillars and the advancement of the inferior part of the infraorbital plate (the origin of the masseter) play a major role in molding the facial topography of A. africanus. The absence of the pillars and the common position of the masseteric origin lead us to define the face of A. afarensis as the most primitive of the australopithecines and allow us to discriminate between its facial morphology and that of A. africanus. The presence of anterior pillars in the face of the latter places it clearly in the robust australopithecine clade.     

Nasal shape,prognathism and adaptation in man

The association between nasal shape, prognathism and the shape of the maxillary dental arch has been examined within samples of Negro and European skulls. Prognathism tends to be accompanied by an increasingly broad and short nose. Particularly high correlations exist between nasal height and the length of the cranial base and between nasal breadth and the distance which separates the upper canine teeth. Regression analysis has yielded quantitative estimates of the effect on a given dimension of variation in one or more of the others. It seems probable that both nasal shape and the maxillary dental arch-prognathism complex may be subject to direct selection by environmental stress. The morphological association between these complexes suggests that a part of the interpopulation variation in prognathism may be a secondary effect of selection acting on the nose. Similarly, selection acting on the dental arch or maxilla could produce secondary changes in the nasal index (i.e. a non-adaptive component of nasal variation).     

A prospective evaluation of the prevalence of submucous cleft palate in patients with isolated cleft lip versus controls.

Although there is an established relationship between cleft lip and overt cleft palate, the relationship between isolated cleft lip and submucous cleft palate has not been investigated. To test the hypothesis that patients with isolated cleft lip have a greater association with submucous cleft palate, a double-armed prospective trial was designed. A study group of 25 consecutive children presenting with an isolated cleft lip, with or without extension through the alveolus but not involving the secondary palate, was compared with a control group of 25 children with no known facial clefts. Eligible patients were examined for the presence of physical criteria associated with classic submucous cleft palate, namely, (1) bifid uvula, (2) absence of the posterior nasal spine, and (3) zona pellucida. Nasoendoscopy was subsequently performed just after induction of general anesthesia, and the findings were correlated with digital palpation of the palatal muscles. Patients who did not satisfy all three physical criteria and in whom nasoendoscopy was distinctly abnormal relative to the control group were classified as having occult submucous cleft palate. Classic submucous cleft palate was found in three study group patients (12 percent), all of whom had flattening or a midline depression of the posterior palate and musculus uvulae on nasoendoscopy and palpable diastasis of the palatal muscles under general anesthesia. An additional six study group patients (24 percent) had similar nasoendoscopic criteria and palpable diastasis of the palatal muscles; they were classified as having occult submucous cleft palate. No submucous cleft palate was identified in the control group. Seventeen patients in the study group had an alveolar cleft with a 53 percent (9 of 17) prevalence of submucous cleft palate. In the present study, classic submucous cleft palate in association with isolated cleft lip was 150 to 600 times the reported prevalence in the general population. All children with an isolated cleft lip should undergo peroral examination and speech/resonance assessment no later than the age of 3 years. Any child with an isolated cleft lip with velopharyngeal inadequacy or before an adenoidectomy should be assessed by flexible nasal endoscopy to avoid missing an occult submucous cleft palate.     

Measurement and study of the nose and face and their correlations in the young adult of Han nationality

The measurement of 13 items in the face and nose of 220 young adults (110 males and 110 females) of the Han nationality between the ages of 18 and 21 years has been done in the Henan Province of China. The means and standard deviations have been obtained, and the significant differences in many items between males and females have been proved. Some items influencing outer nasal shape have been analyzed. The correlations between nose height, nose length, and morphologic facial height and physiognomic facial height have been discussed. The ratio and amount of nasal breadth to facial breadth and nasal breadth to interocular breadth have been compared and analyzed, and the differences among the different races and between the sexes have been explained.     

Cranial base and jaw relationship

The lateral skull radiographs of 124 boys aged approximately 10 years divided equally between the four angle classes were digitized in an effort to establish the relationship between cranial base size and shape and jaw relationship. Comparison of the means for occlusal groups showed a trend from class II to class III as cranial base dimensions and angle decreased. The condyle was also more distally positioned with respect to nasion, point A and the Pterygomaxillary vertical in the class II groups. Cranial base length correlated strongly with maxillary length but weakly with mandibular length. Nevertheless, the size of the maxilla did not influence its prognathism. The cranial base angle was strongly correlated (-0.7) with angle sella-nasion-point B. It is concluded that cranial base size and shape influence mandibular prognathism by determining the anteroposterior position of the condyle relative to the facial profile.