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1.
An analytical morphometrical investigation of fronto facial profile of Plesianthropus transvaalensis was carried out by means of Fourier spectral series. Amplitude of contributors was evaluated in comparison with harmonic sets of a modern skull and two "mosaics" obtained by a convenient merging of segments of modern and hominid skull profiles. Patterns are distinctly different in Plesianthropus and modern profile because amplitude of second harmonic is greater than first in the former and viceversa in the latter; moreover while in Plesianthropus first and second harmonic give the same phase, it does not occur for modern skull. Fourier series of "mosaic" obtained by frontal profile of Plesianthropus and facial profile of modern resembles the set of modern skull while "mosaic" of modern frontal profile and hominid facial one resembles closely pattern of Plesianthropus.  相似文献   

2.
The paper presents a procedure for examining patients with posttraumatic deformities of the middle and upper third of the facial skull on a spiral computed tomograph and the schemes for estimating the size of enophthalmos, which permit elimination of eyeball recession.  相似文献   

3.
The paper considers whether carbonic materials whose contrasting is achieved when they contain 8-12% of metallic boron power may be applied to restore bone defects of the facial skull. Implants of this composition were employed to operate on 4 patients with different defects of the facial skull. A three-projection of SCT image obtained in the "SOFT" mode was used as a way of registration. The results of the studies have indicated that the materials under study have X-ray contrast, a complete biological compatibility, and non-toxicity when they are used in clinical practice.  相似文献   

4.
The pattern of skull growth of the rice rat (Oryzomys palustris natator) over the pre-weaning period of development reveals a characteristic triphasic outline which stems, in part, from the interplay of the external environment and the genetic endowment. Within the triphasic spectrum the neural skull growth exhibits an accelerated rate of growth during the early phases which eventually reverses to a rapid deceleration in the final phase. In contrast, the facial skull growth shows increased growth rate following the decline of the neural group, eventually reaching a slow linear deceleration. Thus the neural components appear to be synchronised to the brain growth while the facial elements gain a new and greater impetus following the neural decline. The general growth of the skull throughout these changes, i.e. triphasic and neural/facial, continues to show a basic slow linear increase.  相似文献   

5.
In Ruminantia, the lacrimal bone forms a considerable part of the facial skeleton, and the morphology of its facial facet is highly variable when compared to other mammals. In this study, we quantify the species-specific variability in size and shape of the lacrimal facial facet in species of Cervidae (deer) and relate it to systematics and various aspects of their ecology and behavior. We sampled 143 skull specimens from 10 genera; 12 Moschus and 3 Tragulus specimens were used as outgroups. We find that size and shape of the lacrimal facial facet allow differentiating most species analyzed here, except for Mazama gouazoubira and Capreolus capreolus. Size and shape of the lacrimal facial facet vary widely across Cervidae regardless of their systematic relationships, ecology or behavior. Thus, we could not detect a unique signature of adaptational criteria in lacrimal morphology. Our data indicate that the lacrimal facial facet scales allometrically with skull size, in particular, the lacrimojugal length scales positively and the lacrimomaxillar length scales negatively. However, correlation analyses did not reveal any differences in the integration of the lacrimal bone with any specific skull module in any of the species compared. Lastly, we could not ascertain any correlation between the size and position of the preorbital depression with the size and shape of the lacrimal facial facet. We conclude that the lacrimal facial facet is highly flexible and may rapidly adjust to its surrounding bones. Its allometric growth appears to be an example of exaptation: changes in size and shape in the context of the increase of the skull length provide lacrimal contacts, in particular, a lacrimojugal one, which may serve to reduce mechanical loads resulting from increasingly larger antlers in large cervids.  相似文献   

6.
The incidence and type of x-ray semeiotics of the skull involvement were studied in 703 patients with endocrine diseases (26 with acromegaly, 36 with hypercorticism, 104 with thyrotoxicosis, 23 with hypothyrosis, 98 with primary hyperparathyrosis, 302 with diabetes mellitus, 114 with hypogonadism). Craniogram analysis involved study of the thickness and structure of the vault bones, shape and size of the skull, status of the sutures, internal plate relief, changes of the base of the skull, of the sella turcica first of all, and facial bones. The characteristic x-ray symptom complexes of the involvement of the skull in some endocrine diseases were distinguished.  相似文献   

7.
The present paper considers the significance of a variety of cranial flexions in the process of orthocephalization of the rat skull between 14 and 60 days postnatally. The study is based on a sample of 27 male rats, who have been x-rayed at 14, 30 and 60 days with subsequent analyses of the photographs obtained. In this period the angle between the cranial base and the facial part of the skull becomes more obtuse, i.e. the skull becomes more orthocranial. The cranial base becomes at the same time more airobasal (lordotic). Angular changes between the individual bones in the cranial vault straightens the vault markedly. By this it becomes orthodorsal. As the angle between the basisphenoid and the parietal bones stays more or less constant between 14 and 60 days, the impression is created that both the anterior and posterior parts of the neural skull rotate upwards relative to this bone complex. Thus, orthocephalization in the period between 14 and 60 days both consists of flexions between the facial and neural parts of the skull (prebasal flexions), and may be more importantly of interosseous ventral and dorsal flexions.  相似文献   

8.
In order to avoid the arbitrary division of biological structures, rational polynomial interpolants are utilized to study growth. The major advantage of this method is the elimination of artificial internal element boundaries through anatomical structures. Since the boundary element methodology is employed in the finite element setting, other benefits, without additional computer coding, include the ability to use elements with any number of sides and reference frame invariance. Longitudinal landmark coordinates from midsagittal X-ray tracings of 22 albino female rat skulls of various ages were averaged. The skull was partitioned into three macroelements: a neural skull and two functionally distinct portions of the facial skull--olfactory and respiratory. The digital computer programming was carried out in the computer mathematics environment of Mathematica. Maximum elongation ratios were calculated for approximately 400 interior points. The elongation ratios in the neural skull compared well with previously documented growth behavior of internal brain structures. The calculated ratios from the facial skull were used to analyze the behavior of macroelement interpolation close to common anatomical boundaries.  相似文献   

9.
Authors present their own experience with the embolization of the external carotid artery branches. The main indications to embolization included well vascularized and hemorrhagic brain tumors in facial part of the skull, mainly meningiomas, juvenile angiofibromas, and angioneuromyomas. Embolization of external carotid artery was performed in 15 patients. Complete impatience of blood vessel supplying the tumor was achieved in 12 cases, but it was incomplete in 3 cases. Single serious complication in the form of hemiplegia was noted. There were also mild complications in 5 patients, which did not require any intervention.  相似文献   

10.
An external fixation apparatus immobilized to the skull has been used with satisfactory results in 15 cases of significant retrusion of the middle third of the face in which intermaxillary wiring and facial suspension had proved inadequate. The retrusion was a consequence of trauma or secondary to congenital malformation.This apparatus, developed by Delbet and Tessier, would be useful in difficult cases, such as for edentulous patients, and is an alternative to bone grafting.  相似文献   

11.
Simulation of the biting action of the gorilla was made by using a macerated skull of the gorilla. Strains in the facial skeleton produced by this simulation were measured by the wire strain gauge. Some stress analyses were made from these strains and were compared with those of the human facial skeleton. The strains in the facial skeleton of the gorilla indicate fundamentally the same deformation during biting action as do those of the human facial skeleton, but differences between both facial skeletons also appear. Generally the force of the temporalis tends to strain the facial skeleton more compressively while the force of the masseter does so more tensilely. They produce qualitatively the same but quantitatively different strains or stresses.  相似文献   

12.
By following the development of individual mice from birth to 200 days of age, it was found that the skull of the homozygous mutant (dwdw) was 5% shorter than that of the normal phenotype at birth and some 30% shorter at 200 days of age. During post-natal growth of the skull, the cranium was least altered but the facial skeleton was greatly affected. The differences seen in different parts of the skull are attributed to the peak growth velocities of the various parts occurring at different times.  相似文献   

13.
Two patients with partial deletion of the short arm of chromosome 10 are described. They showed most of the features observed in twenty other known patients, including growth retardation, mental deficiency, abnormally shaped skull, distinct facial dysmorphisms, cardiac and genitourinary malformations, and limbs anomalies. One of our patients also had features of the DiGeorge sequence, which has been found in five other cases with this imbalance.  相似文献   

14.
In order to predict and evaluate injury mechanism and biomechanical response of the facial impact on head injury in a crash accident. With the combined modern medical imaging technologies, namely computed tomography (CT) and magnetic resonance imaging (MRI), both geometric and finite element (FE) models for human head-neck with detailed cranio-facial structure were developed. The cadaveric head impact tests were conducted to validate the headneck finite element model. The intracranial pressure, skull dynamic response and skull-brain relative displacement of the whole head-neck model were compared with experimental data. Nine typical cases of facial traffic accidents were simulated, with the individual stress wave propagation paths to the intracranial contents through the facial and cranial skeleton being discussed thoroughly. Intracranial pressure, von Mises stress and shear stress distribution were achieved. It is proved that facial structure dissipates a large amount of impact energy to protect the brain in its most natural way. The propagation path and distribution of stress wave in the skull and brain determine the mechanism of brain impact injury, which provides a theoretic basis for the diagnosis, treatment and protection of craniocerebral injury caused by facial impact.  相似文献   

15.
Unilateral electrolytic lesions were made in the left-side facial motor nucleus (FMNu) of six Sprague-Dawley rats at 35 days of age in order to correlate craniofacial sequelae with changed motoneuron function. Experimental and control rats were killed at 22, 32, 42, and 52 days postoperatively to provide muscle weight, brain histology, and dry skull preparations for analyses. Dissection, muscle weight, motoneuron count, and osteometric data revealed that lesion-side facial and masticatory muscles were affected by the lesions. Paired t-tests indicated that significant differences existed between weights of experimental lesion- and nonlesion-side anterior digastric, temporalis, masseteric complex, and medial pterygoid muscles, numbers of facial and trigeminal motoneurons, and several skeletal dimensions of the skull. Basi-cranial dimensions of experimental animals were least affected by the lesion, whereas zygomatic arch, dorsal facial region, and mandibular condyle dimensions were most affected. Statistical analyses also detected significant differences between experimental and control groups for several skeletal dimensions of the skull. Data indicated that damage to the trigeminal motor nucleus (TMNu) was secondary to the primary lesion in the FMNu. Motoneurons within the facial and trigeminal neuromuscular complexes (FNC and TNC) play an important role in craniofacial growth and development.  相似文献   

16.
Facial heights, i.e. the vertical distances between the superior and inferior limits of facial compartments, contribute to the orientation of the viscerocranium in the primate skull. In humans, vertical facial variation is among the main sources of diversity and frequently associated with an integrated suite of other cranio-mandibular traits. Facial heights and kyphosis are also important factors in interspecific variation and models of hominoid evolution. The ontogenetic determination of adult facial orientation and its relation to phylogenetic variation are unclear, but crucial in all previously mentioned respects. We addressed these issues in a sample of 175 humans and chimpanzees with Procrustes based geometric morphometrics, testing hypotheses of interspecific similarity in postnatal ontogenetic trajectories, early versus later ontogenetic facial pattern determination, and a developmental model of morphological integration. We analyzed the contribution of postnatal morphogenesis to adult vertical facial variation by partitioning morphological variation into a portion of pure growth allometry and a non-allometric fraction. A statistically significant difference of growth-allometries revealed that in both species growth established the adult skull proportions by vertical facial expansion, but while in chimpanzees the complete viscerocranium showed reorientation, in humans only the lower face was modified. In both species the results support a hypothesis of early facial pattern determination. A coincident emergence of morphological traits favors a hypothesis of developmental integration of the face, excluding traits of the basi- and neurocranium. Interspecific differences in integration may have implications for evolutionary studies. The present findings indicate that growth establishes the adult skull proportions and integrates principal facial orientation patterns, already there in early postnatal ontogeny.  相似文献   

17.
Normal macroscopic and roentgenographic features of the skull of the ferret (Mustela putorius furo) were examined and described. Data were based on a sample of 100 (50 male and 50 female) adult ferrets of known body weight and age. The skull was described macroscopically according to six standard views, i.e. dorsal, lateral, ventral, caudal, cranial and midsagittal. The mandible was described separately. The roentgenographic characteristics of the ferret skull were demonstrated only in lateral and dorsoventral projections. Furthermore, the skull length and width as well as the minimum frontal width were measured, and skull indices were derived from relevant measurements. Sexual dimorphism was examined both morphologically and craniometrically. Besides the common features of a carnivore skull, the ferret skull is relatively elongated and flat with a short facial region. The skulls of adult male ferrets are about 17% longer and 22% wider than those of the females. Significant sexual dimorphism also exists regarding certain skull indices. The general features and some dimensional parameters of the adult ferret skull support the contention that the ferret would be an interesting and workable alternative animal model in craniofacial research.  相似文献   

18.
During systematic archaelogical excavations of the early medieval kingdom of Serbia, and adult male skull belonging to the skeleton of a Roman individual was unearthed at Babrež site in the Ras region. A supernumerary bone was found interposed between the frontal bones of the skull and the facial skeleton. Paleopathological investigation and CT reconstruction proved that this skull had been deformed during foetal development due to a disorder or disease affecting the mother. This probably led to the formation of the supernumerary Glabellar bone in the frontal region. This is the first case of Os Glabellae recorded so far.  相似文献   

19.
Feminization of the forehead: contour changing to improve female aesthetics   总被引:1,自引:0,他引:1  
Anthropologists have identified those characteristics which enable them to differentiate the male from the female skull. Some women have masculine skeletal characteristics which, if changed, would improve their facial appearance. Changing the skeletal configuration through bony contouring of the craniofacial skeleton for aesthetic purposes is a natural spinoff of craniomaxillofacial surgery. Techniques for sculpturing the masculine characteristics present in the foreheads of some females are discussed. The deformity has been divided into three subdivisions. Group 1 patients can be treated through bony contouring alone; group 2 patients require bony contouring in conjunction with a methyl methacrylate cranioplasty; and group 3 are those patients with a more severe deformity requiring osteotomies. The technique, results, complications, and patient acceptance are discussed.  相似文献   

20.
Skull length is the measurement most commonly used as a standard against which other aspects of cranial morphology are compared to derive an index of relative size or proportions. However, skull length is composed of two different functional components, facial skull and cerebral skull, which vary independently and have different scaling relationships with body size. An analysis of carnivore skull shape with measurements standardized against basicranium length produced very different results than an analysis using skull length as the standard. For example, expressions of relative size of cranial measurements were reduced by 13% in mustelids and increased by 20% in canids, reflecting removal of jaw length (short in mustelids and long in canids) from the comparative standard (basicranial axis length). Cranial measurements scale with higher allometric exponents against basicranial axis length than against skull length.  相似文献   

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