Search

Realistic biomechanical models of the human head should accurately reflect the mechanical properties of all neurocranial bones. Previous studies predominantly focused on static testing setups, males, restricted age ranges and scarcely investigated the temporal area. This given study determined the biomechanical properties of 64 human neurocranial samples (age range of 3 weeks to 94 years) using testing velocities of 2.5, 3.0 and 3.5 m/s in a three-point bending setup. Maximum forces were higher with increasing testing velocities (p ≤ 0.031) but bending strengths only revealed insignificant increases (p ≥ 0.052). The maximum force positively correlated with the sample thickness (p ≤ 0.012 at 2.0 m/s and 3.0 m/s) and bending strength negatively correlated with both age (p ≤ 0.041) and sample thickness (p ≤ 0.036). All parameters were independent of sex (p ≥ 0.120) apart from a higher bending strength of females (p = 0.040) for the 3.5 -m/s group. All parameters were independent of the post mortem interval (p ≥ 0.061). This study provides novel insights into the dynamic mechanical properties of distinct neurocranial bones over an age range spanning almost one century. It is concluded that the former are age-, site- and thickness-dependent, whereas sex dependence needs further investigation. [ABSTRACT FROM AUTHOR]

Objectives: Although the homology of the Neanderthal occipital bun and anatomically modern human "hemi‐bun" has long been debated, little is known about the developmental timing and patterning of these two patterns of prominent occipital squama convexity. In this study, occipital hemi‐bun ontogeny and cranial shape covariation are assessed in a comparative extant human sample. Materials and Methods: Two‐dimensional geometric morphometric methods were used to investigate hemi‐bun development in a longitudinal sample of growth study cephalograms representing extant human subjects predominantly of European ancestry. Subjects were each measured at three distinct age points, ranging from 3.0 to 20.4 years, and two‐block partial least squares analysis was used to assess patterns of covariation between midsagittal occipital bone morphology and other aspects of craniofacial shape. Results: Occipital hemi‐bun morphology, when present, was found to develop early in ontogeny, in association with anteroposterior elongation of the frontal and parietal bones. No significant pattern of covariation was found between occipital hemi‐bun shape and cranial/basicranial breadth, basicranial length, basicranial angle, or midfacial prognathism. Discussion: This study suggests that the occipital hemi‐bun, at least in this extant human population, should not be considered an independent trait, as its development is closely linked to shape variation in the frontal and parietal bones. Importantly, these results suggest that occipital hemi‐bun morphology is not significantly influenced by basicranial morphology during development, but instead covaries with changes in midsagittal neurocranial vault shape. [ABSTRACT FROM AUTHOR]

A new species of moray eel, Diaphenchelys dalmatian is described based on five specimens [289.8-503.0 mm total length (TL)] collected from the western coast of peninsular Thailand and the Gulf of Thailand. It can be easily distinguished from Diaphenchelys pelonates McCosker and Randall 2007, another species of the genus Diaphenchelys McCosker and Randall 2007, by its coloration (ground color white with brown dalmatian-like spots vs. brown with pale vermiculate pattern). The present new species also differs from D. pelonates in its longer tail (62.0-64.6% TL vs. 59.6-61.5%), fewer infraorbital pores along upper lip (three vs. four), fewer mandibular pores (five vs. six or seven), and fewer vertebral counts (preanal vertebrae 43-46 vs. 55-58; total 126-131 vs. 153-155). Diaphenchelys is closely similar to the genus Strophidon McClelland 1844 in the shape of neurocranium, the elongate body, low vertical fins, eye location, jaw shape, and presence of inner mandibular teeth. However, both differ in the vertebral counts (126-155 in Diaphenchelys vs. 164-208 in Strophidon) and coloration (prominent pattern vs. uniform). [ABSTRACT FROM AUTHOR]

Skeleton of batoids has been important to outline kinship relations in this group. Therefore, the objective of this work is describing the anatomy of five species of genus Urotrygon. Skeleton of Urotrygonids displayed a common morphological pattern, with the following differences: 1) preorbital processes are reduced in Urotrygon nana and Urotrygon munda, and developed on all other species; 2) the first postorbital process is reduced in U. nana and U. munda; 3) the first hypobranchial cartilage is fragmented only in Urotrygon rogersi; 4) only Urotrygon aspidura had a bridge in the basibranchial cartilage; lateral processes of the synarcuale in U. aspidura are long and thin, while short and wide in U. nana and U. rogersi; 6) U. nana has only one single fenestra in its pectoral girdle, while other species have two; 7) In U. nana and U. munda the mesopterygium is rounded, but in all other species it is elongated in its anterior part; 8) U. nana y U. munda have a more arched pelvic girdle. Species with more plesiomorphic characters are U. nana and U. munda. [ABSTRACT FROM AUTHOR]

Placoderms are considered as the first jawed vertebrates and constitute a paraphyletic group in the stem-gnathostome grade. The acanthothoracid placoderms are among the phylogenetically most basal and morphologically primitive gnathostomes, but their neurocranial anatomy is poorly understood. Here we present a near-complete three-dimensional skull of Romundina stellina, a small Early Devonian acanthothoracid from the Canadian Arctic Archipelago, scanned with propagation phase contrast microtomography at a 7.46 μm isotropic voxel size at the European Synchrotron Radiation Facility, Grenoble, France. This is the first model of an early gnathostome skull produced using this technique, and as such represents a major advance in objectivity compared to past descriptions of placoderm neurocrania on the basis of grinding series. Despite some loss of material along an oblique crack, most of the internal structures are remarkably preserved, and most of the missing structures can be reconstructed by symmetry. This virtual approach offers the possibility to connect with certainty all the external foramina to the blood and nerve canals and the central structures, and thus identify accurate homologies without destroying the specimen. The high level of detail enables description of the main arterial, venous and nerve canals of the skull, and other perichondrally ossified endocranial structures such as the palatoquadrate articulations, the endocranial cavity and the inner ear cavities. The braincase morphology appears less extreme than that of Brindabellaspis, and is in some respects more reminiscent of a basal arthrodire such as Kujdanowiaspis. [ABSTRACT FROM AUTHOR]

Long bones and the cranial base are both formed through endochondral ossification. Elongation of long bones is primarily through the growth plate, which is a cartilaginous structure at the end of long bones made up of chondrocytes. Growth plate chondrocytes are organized in columns along the longitudinal axis of bone growth. The cranial base is the growth center of the neurocranium. Synchondroses, consisting of mirror-image growth plates, are critical for cranial base elongation and development. Over the last decade, considerable progress has been made in determining the roles of the parathyroid hormone-related protein, Indian hedgehog, fibroblast growth factor, bone morphogenetic protein, and Wnt signaling pathways in various aspects of skeletal development. Furthermore, recent evidence indicates the important role of the primary cilia signaling pathway in bone elongation. Here, we review the development of the growth plate and cranial synchondrosis and the regulation by the above-mentioned signaling pathways, highlighting the similarities and differences between these 2 structures. [ABSTRACT FROM AUTHOR]

The main goals of this study were to evaluate the distinctiveness of Homo erectus neurocranial shape relative to other closely related species, and assess the likelihood that particular fossils were correctly attributed to H. erectus given how shape variation related to geography, time and brain size. This was accomplished through analyses of several sets of landmarks designed to maximize the fossil sample, including 24 putative H. erectus fossils. The question of taxonomic differentiation was initially assessed for the type specimen (Trinil II) and morphologically similar Sangiran fossils and subsequently for increasingly inclusive definitions of H. erectus . Results indicated that H. erectus fossils from China, Indonesia, Georgia and East Africa shared a neurocranial shape that was distinct from that of other Plio-Pleistocene Homo taxa, a pattern only partially accounted for by brain size. Early Indonesian H. erectus formed a morphological “bridge” between earlier and later populations assigned to H. erectus from Africa and Asia, respectively. These results were combined with discrete characters to create a more complete species definition for H. erectus . There were two notable exceptions to the general pattern of H. erectus uniqueness. The 0.8–1.0 Ma (millions of years ago) Daka calvaria from Ethiopia consistently grouped with mid-Pleistocene Homo , including Bodo and Kabwe, rather than African or Asian H. erectus . In addition, Daka also exhibited several traits derived for mid-Pleistocene Homo , and its scaling pattern mirrored mid-Pleistocene Homo rather than H. erectus . Daka may have belonged to an “advanced” H. erectus population close to the root of Homo heidelbergensis sensu lato (s.l.) , or to an early population of H. heidelbergensis s.l. . The 1.5 Ma KNM-ER 42700 specimen from Kenya exhibited a unique calvarial shape distinct from H. erectus despite the exclusion of problematic landmarks from the frontal bone. These unique aspects of shape were not present in two other subadult fossils, KNM-WT 15000 and D2700. [ABSTRACT FROM AUTHOR]

The early Late Pleistocene late archaic human remains from Xujiayao, northern China, reveal several abnormalities of the neurocranial vault. The Xujiayao site is located on the northwestern boundary of the Nihewan Basin, and on the basis of various indicators, it dates to the early Late Pleistocene. Among the 15 human neurocranial elements found at Xujiayao in the 1970s, three elements show minor traumatic lesions of the external table: the largely complete Xujiayao 5a immature parietal bone, the Xujiayao 8 small piece of anterior right parietal bone and the Xujiayao 12 partial occipital bone. The lesions are all superior to the temporal or nuchal lines and hence were subcutaneous, covered only by the pericranium, the galea aponeurotica and the overlying skin. The external tables are variably concave with irregular bone within the bony depressions, and the diploë show varying degrees of involvement. The Xujiayao abnormalities join a series of minor neurocranial healed lesions among Pleistocene humans, as well as more pronounced healed neurocranial and facial trauma. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The pampas deer Ozotoceros bezoarticus is a medium-sized, elegant, and lightly built cervid that was once a characteristic inhabitant of open grasslands across a wide geographical distribution in South America. In Argentina, the subspecies Ozotoceros bezoarticus celer is the most southern and abundant populations and relatively well represented in osteological collections permitting a morphometric study of cranial ontogeny. We measured 17 cranial variables on an ontogenetic series in order to evaluate the multivariate allometry of neurocranial and splanchnocranial components through developmental stages. The cranial ontogenetic pattern in O. b. celer exhibits a conservative plan in which both sexes share most of the allometric trends except in three variables related to the rostrum. Isometry was detected in 9 out of 17 variables, whereas four grows with negative allometry, and only nasal length showed positive allometry. As for most mammals, those variables related to the neurocranial components and sensorial capsules exhibit negative allometry. The growth of the rostrum indicates that both sexes have longer face than younger. However, the lack of allometry in most of the variables seems to be supporting the idea of a younger with the general appearance of an adult but smaller size. [ABSTRACT FROM AUTHOR]

Qijianglong guokr, gen. et sp. nov., represents a mamenchisaurid eusauropod from the Late Jurassic of southern China. The holotype consists of an incomplete skull, partly articulated axial skeleton, and fragmentary appendicular skeleton. A well-preserved braincase and skull roof provide rare insights into the poorly known neurocranial anatomy of mamenchisaurids and reveal a unique combination of characters such as an accessory tuber at the base of planar basipterygoid process and parietal excluding frontal from the anterior margin of the supratemporal fenestra. The cervical vertebrae have a distinct finger-like process extending from the postzygapophyseal process beside a zygapophyseal contact. Qijianglong is the first mamenchisaurid from the Late Jurassic of China that is definitively distinct from Mamenchisaurus, indicating greater morphological and taxonomic diversity of the poorly represented Late Jurassic mamenchisaurids. The occurrence of Qijianglong is consistent with a scenario in which mamenchisaurids formed an endemic sauropod fauna in the Late Jurassic of Asia. Phylogenetically, Qijianglong represents a relatively plesiomorphic mamenchisaurid lineage. The mamenchisaurids form an ancient clade of basal eusauropod dinosaurs that likely appeared in the Early Jurassic. A cladistic analysis highlights the interrelationships of mamenchisaurids and suggests guidelines for mamenchisaurid taxonomic revision. It may be desirable to restrict generic names to the type species in order to avoid confusion. [ABSTRACT FROM AUTHOR]

In the present study, we analyzed postnatal ontogenetic integration among morphological traits of the human neurocranium. Particularly, the covariation between the vault and the base during postnatal life was assessed. Since the association between these regions may depend on the generalized change produced by allometry, we tested its effect on their covariation. On a sample of adults and subadults ranging from 0 to 31 years, 3D coordinates of neurocranial landmarks and semilandmarks were digitized and geometric morphometric technics were applied. Main aspects of shape variation were examined using Principal Components analysis. Covariation between the vault and the base was examined by Partial Least Squares analysis. According to our results, the vault and the base covary strongly during postnatal ontogeny and their relation depends largely on allometry. Two size variables were studied: centroid size, which was obtained from the recorded morphometric points, and endocranial volume, taken as an estimation of brain size. Although growing brain was found to be a developmental process that contributes to covariation among neurocranial traits, there would be other factors that exert their influence during ontogeny. These results lead to reconsider cranial morphological evolution taking into account the developmental constraints given by ontogenetic patterns of integration and reinforcing the idea that in human evolution a suite of relevant characters may be fuelled by few developmental processes. [ABSTRACT FROM AUTHOR]

ABSTRACT Midfacial reduction in primates has been explained as a byproduct of other growth patterns, especially the convergent orbits. This is at once an evolutionary and developmental explanation for relatively short snouts in most modern primates. Here, we use histological sections of perinatal nonhuman primates (tamarin, tarsier, loris) to investigate how orbital morphology emerges during ontogeny in selected primates compared to another euarchontan ( Tupaia glis). We annotated serial histological sections for location of osteoclasts or osteoblasts, and used these to create three-dimensional 'modeling maps' showing perinatal growth patterns of the facial skeleton. In addition, in one specimen we transferred annotations from histological sections to CT slices, to create a rotatable 3D volume that shows orbital modeling. Our findings suggest that growth in the competing orbital and neurocranial functional matrices differs among species, influencing modeling patterns. Distinctions among species are observed in the frontal bone, at a shared interface between the endocranial fossa and the orbit. The medial orbital wall is extensively resorptive in primates, whereas the medial orbit is generally depositional in Tupaia. As hypothesized, the orbital soft tissues encroach on available interorbital space. However, eye size cannot, by itself, explain the extent of reduction of the olfactory recess. In Loris, the posterior portion of medial orbit differed from the other primates. It showed evidence of outward drift where the olfactory bulb increased in cross-sectional area. We suggest the olfactory bulbs are significant to orbit position in strepsirrhines, influencing an expanded interorbital breadth at early stages of development. Am J Phys Anthropol 154:424-435, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The new transcutaneous bone conduction implant (BCI) Bonebridge (BB, MED-EL) allows the skin to remain intact and therefore overcomes some issues related to percutaneous systems, such as skin reaction around the external screw and cosmetic complaints. According to manufacturer, BB is MRI conditional up to 1,5 Tesla (T). The artefact of the neurocranium after BB implantation is extensive as shown in the present report. This has to be taken into account when patients suffering conductive, mixed or single-sided hearing loss with candidacy for a BCI are counselled. In patients with comorbid intracranial tumour or other diseases of the brain that require imaging control scans with MRI percutaneous, BCI should be the implant of choice considering the very small artefact of the percutaneous screw in MRI. [ABSTRACT FROM AUTHOR]

Background: Equipped with an effective predatory feeding mechanism enhanced by large and sharp teeth, pointed snout and elongate body, saurichthyiform fishes are considered common fish-eaters in the early Mesozoic aquatic ecosystems. Additionally, because of the similar body plan across species, saurichthyiforms are also regarded evolutionally conservative, with few morphological and ecological changes during their long history. However, their phylogenetic affinity remains unclear as to whether they are chondrostean, neopterygian or stem-actinopteran, and likewise the intrarelationships of the group have rarely been explored. Methodology/Principal Findings: Here we report a new saurichthyiform from the Middle Triassic of Guizhou, China, based on the well-preserved specimens including a 3-D braincase. The new taxon, Yelangichthys macrocephalus gen. et sp. nov., is unique among saurichthyiforms in having a peculiar neurocranium with a broad orbital tectum, paired posterior myodomes, a deep, transverse fossa in the posterodorsal part of the orbit, and a feeding mechanism structured for durophagy. Phylogenetic analysis places Yelangichthys gen. nov. at the most basal position in the Saurichthyiformes as the sister to Saurichthyidae, and a new family Yelangichthyidae is erected to include only Y. macrocephalus gen. et sp. nov. The monophyly of the Chondrostei comprising [Saurichthyiformes + Acipenseriformes] Birgeriiformes is supported, but not the monophyly of Saurichthys, the type genus of Saurichthyidae. With its outstanding osteological details, Yelangichthys gen. nov. greatly increases the neurocranial variations in saurichthyiforms, and its novel feeding structure suggests the consumption of hard-preys instead of fishes. Conclusions/Significance: Our findings highlight the detailed osteology of a saurichthyiform braincase and its feeding design. We suggest that saurichthyiforms are closely allied to the Acipenseriformes. Saurichthyiforms were very diverse in the cranial osteology and they might have undergone a rapid evolutionary radiation via, for the new material here, transforming the feeding mechanism and thus exploiting the food resources unsuitable for other saurichthyiforms. [ABSTRACT FROM AUTHOR]

Abstract: Hominins that differ from Homo erectus, the Neanderthals, and recent humans are known from Middle Pleistocene localities across the Old World. The taxonomic status of these populations has been clouded by controversy. Perhaps the most critical problem has been an incomplete understanding of variation in skull form. Here, both H. erectus and later mid-Pleistocene hominins are the focus of an investigation aimed at clarifying the relationships among brain volume, basicranial dimensions, neurocranial shape, and certain facial characters. Brain size in H. erectus averages about 950 cm3, while in a series of Middle Pleistocene crania from Africa and Europe, volume is about 1230 cm3. If encephalization is the primary mechanism operating in the mid-Pleistocene, then diverse aspects of cranial form cannot all be treated as independent variables. Correlation is utilized to examine the associations among measurements for more than 30 H. erectus crania that are reasonably well preserved. A similar approach is used with the Middle Pleistocene sample. Patterns of covariation are compared in order to assess integration. Next, factor analysis is applied to the H. erectus specimens in an attempt to identify modules, tightly integrated traits that can evolve independently. Studies of the variation within H. erectus are followed by direct comparisons with the Middle Pleistocene population. Discriminant functions facilitate the description of intergroup differences. Traits that vary independently from brain volume include anterior frontal broadening, lateral expansion of the parietal vault, elevation of the lambda–inion chord, and rounding of the sagittal contour of the occipital. This finding helps to resolve the problem of species recognition. Neurocranial proportions as well as characters from the cranial base and face can be incorporated into a differential diagnosis for the mid-Pleistocene sample. Evidence presented here supports arguments for speciation in the Middle Pleistocene. [Copyright &y& Elsevier]

Ontogenetic changes in the skull of Lycalopex culpaeus were studied in relation to feeding function and performance at different age classes. Most cranial changes occurred in the orbitotemporal region and consisted of the visible appearance of structures that were later found to be absent in juveniles. These changes were related to the development of the adult skull in order to capture, kill, and process prey. In general, fusion occurred earlier in neurocranial sutures than in the splachnocranium, although rostral sutures never became fused. The cranial sutures of culpeo are conservative, displaying few changes in suture type but some in suture fusion sequence. These modifications occur during the first year, from the late juvenile stages, when individuals are similar to adults in general appearance and body size as well as in skull size. However, it was noted that basicranial synchondroses became fused in the adult stages, indicating that longitudinal growth could extend until this latter time. This could be indicative not only of size change in adult specimens but also of shape change. [ABSTRACT FROM AUTHOR]

At the level of the inferior viscerocranium, the strong mastication forces determine the constitution of three resistance structures : the superior mandibular arch, the inferior mandibular arch, the oblique mandibular arch. [ABSTRACT FROM AUTHOR]

We conducted 2 studies to determine whether dense and thin NCR schedules exert different influences over behavior and whether these influences change as dense schedules are thinned. In Study 1, we observed that thin as well as dense NCR schedules effectively decreased problem behavior exhibited by 3 individuals. In Study 2, we compared the effects of 2 NCR schedules in multielement designs, one with and the other without an extinction (EXT) component, while both schedules were thinned. Problem behavior remained low as the NCR schedule with EXT was thinned, but either (a) did not decrease initially or (b) subsequently increased as the NCR schedule without EXT was thinned. These results suggest that dense schedules of NCR decrease behavior by altering its motivating operation but that extinction occurs as the NCR schedule is thinned. The benefits and limitations of using dense or thin NCR schedules are discussed. [ABSTRACT FROM AUTHOR]

Background: The authors described their surgical technique for scaphocephaly in relatively older infants who are 5 months old or over. The technique is a kind of hybrid of distraction osteogenesis utilizing skull expanders and a traditional cranial reconstruction procedure. Surgery: The surgery usually consists of four procedures. The first is to make strip craniotomy over the superior sagittal sinus (SSS) from the major fontanelle to the minor one. The second is the occipital craniotomy for the occipital bossing. The occipital bone flap undergoes barrel stave osteotomy and is repositioned later. The third is placement of skull expander for distraction osteogenesis. Bidirectional small strip craniotomy is made along the coronal and lambdoid sutures, then transverse cutting is added to make a hinge point near the base of the parietal bone. Two to three skull expanders are placed crossing the SSS. The last procedure is radial-oriented osteotomy on the dorsal end of frontal bone to meet the elevated, expanded parietal bone. Skull expansion starts within a week with 5 mm/week base up to 20 to 30 mm. Exposed shafts of the expander are cut at the end of skull expansion. Discussion: Process of osteogenesis is followed at an outpatient clinic, and the expanders are removed 4 to 6 months later after confirming the sufficient ossification. An advantage of our procedure is that maximum skull expansion is possible with minimum regression after distraction osteogenesis in the long term. Limited craniotomy enables limited blood loss. The skin trouble caused by stretching can be avoided. No postoperative helmet is required. A disadvantage is that the procedure leaves a foreign body on the skull for several months and requires additional surgery for removal. [ABSTRACT FROM AUTHOR]

Abstract: Background/Aim: Computed Tomography (CT) is a powerful tool in craniofacial research that focuses on morphological variation. In this field, an ontogenetic approach has been taken to study the developmental sources of variation and to understand the basis of morphological evolution. This work aimed to determine measurement error (ME) in cranial CT in diverse developmental stages and to characterize how this error relates to different types of landmarks. Material and methods: We used a sample of fifteen skulls ranging from 0 to 31 years. Two observers placed landmarks in each image three times. Measurement error was assessed before and after Generalized Procrustes Analysis. Results: The results indicated that ME is larger in neurocranial structures, which are described mainly by type III landmarks and semilandmarks. In addition, adult and infant specimens showed the same level of ME. These results are specially relevant in the context of craniofacial growth research. Conclusion: CT images have become a frequent evidence to study cranial variation. Evaluation of ME gives insight into the potential source of error in interpreting results. Neural structures present higher ME which is mainly associated to landmark localization. However, this error is irrespective of age. If landmarks are correctly selected, they can be analyzed with the same level of reliability in adults and subadults. [Copyright &y& Elsevier]

Copyright of Journal of Orofacial Orthopedics/Fortschritte der Kieferorthopadie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study discusses the indications, outcomes, and complications in patients that underwent osseointegrated implantation for skull base rehabilitation. We conducted a retrospective review of eight patients with skull base defects who had undergone implantation of a facial prosthetic retention devicebone-anchored hearing aid at a tertiary academic referral center. Descriptive analysis of applications, techniques, outcomes, and complications were reviewed. The majority of patients were males (n=6) with previously diagnosed skull base malignancy (n=5) with an average age of 46 (range, 14 to 77). All patients received an implanted facial prosthetic device either for an aural (n=7) or orbital (n=1) prosthesis. There were only two complications that included infection (n=1) and implant extrusion (n=1). Osseointegrated implantation of abutments for anchoring prosthetic devices in patients for skull base rehabilitation provides an excellent cosmetic option with minimal complications. [ABSTRACT FROM AUTHOR]

Recent advances in Computer Aided Design and Manufacturing techniques (CAD/CAM) have facilitated the rapid and precise construction of customized implants used for craniofacial reconstruction. Data of the patients' trauma, acquired through Computer Topographies (CT), provide sufficient information with regard to the defect contour profile, thus allowing a thorough preoperative evaluation whilst ensuring excellent implant precision. During the selection, however, of a suitable implant material for the specific trauma, the mechanical aspects of the implant have to be considered. This investigation aims to assess the mechanical strength, the shock resistance and the critical deflection of cranial implants manufactured with two commonly used materials, Polymethylmethacrylate (PMMA) and Ti6Al4V. Even though the strength properties of Ti-alloys are far superior to those of PMMA, there are several aspects that may act in advantage of PMMA, e.g., it is known that discontinuities in the elastic modulus of adjoined parts (bone-implant) lead to bone resorption thus loosening the fixation of the implant over time.The implant design and fixation was the same in both cases allowing a direct comparison of the implant behavior for various loads. Finite Element Methods (FEM) assisted procedures were employed, providing a valuable insight to the neurocranial protection granted by these implants. [ABSTRACT FROM AUTHOR]

In this article, the authors are presenting their experience and the results with combined craniofacial resection of anterior skull base tumors based on a review of 27 constitutive cases. Our data are evaluated in comparison to other major centers in other parts of the world, and possible factors that might influence surgical outcome and survival are discussed. Twenty-seven patients diagnosed with anterior skull base tumors between 1999 and 2009 were treated by combined craniofacial resection. Of these patients, there were 19 males (70, 3%) and eight females (29, 7%). The age ranged between 11 and 75 years (mean = 45.9 ± 17.6 years). The follow-up period ranged between 14 and 123 months (avarage = 74 months). The most common presenting symptoms were nasal obstruction and vision disturbance (11 patients for each −40.7%). Total resection was achieved in 24 patients (89%), while subtotal resection was done in three patients (11%). The most common complication was CSF fistule with rhinorrhea, which occurred in five patients (18.5%). Eight patients had recurrences at the time of this long-term follow-up. There were two mortalities in the early postoperative period and seven deaths in the long-term follow-up (overall mortality, 33.3%). The overall 5-year overall survival for all patients in our series was 70.4%. The 5-year overall survival was 62% for patients with malignant tumors and 100% for patients with benign tumors. Combined craniofacial resection of tumors of the anterior skull base is an effective approach for the management of these pathologies. The effectiveness is clearly demonstrated by the clinical results and outcomes of these patients' groups. The favorable prognosis is enhanced by significantly by total resection with negative tumor margins. [ABSTRACT FROM AUTHOR]

The 3.5-Myr-old hominin cranium KNM-WT 40000 from Lomekwi, west of Lake Turkana, has been assigned to a new hominin genus and species, Kenyanthropus platyops, on the basis of a unique combination of derived facial and primitive neurocranial features. Central to the diagnosis of K. platyops is the morphology of the maxilla, characterized by a flat and relatively orthognathic subnasal region, anteriorly placed zygomatic processes and small molars. To study this morphology in more detail, we compare the maxillae of African Plio-Pleistocene hominin fossils and samples of modern humans, chimpanzees and gorillas, using conventional and geometric morphometric methods. Computed tomography scans and detailed preparation of the KNM-WT 40000 maxilla enable comprehensive assessment of post-mortem changes, so that landmark data characterizing the morphology can be corrected for distortion. Based on a substantially larger comparative sample than previously available, the results of statistical analyses show that KNM-WT 40000 is indeed significantly different from and falls outside the known range of variation of species of Australopithecus and Paranthropus, contemporary Australopithecus afarensis in particular. These results support the attribution of KNM-WT 40000 to a separate species and the notion that hominin taxonomic diversity in Africa extends back well into the Middle Pliocene. [ABSTRACT FROM AUTHOR]

Abstract: This study employs juvenile cranial data derived from collections dating to between about 5000 years ago and the present in order to investigate how differences in cranial growth trajectories contributed to inter-group variation in cranial shape among temporally defined Japanese populations. As gene influx from the Asian mainland was insignificant after the Yayoi period (c. CE 300), differences in adult cranial shape among later assemblages from Japan are probably related to developmental adaptations to environmental change. Comparing cranial growth trajectories among groups from different time periods allows indirect testing of several hypotheses about secular changes in cranial growth, including thermoregulatory adaptation, change in levels of masticatory stress, and change in levels of physiological stress. Differences in neurocranial proportions among groups with contrasting adult cranial shapes were found to be already pronounced for the infant cohort (0–3 years of age) and actually tended to decline slightly within later age ranges; differences in mandibular shape were unremarkable early in life, but became more pronounced after infancy. Consequently, changes in chewing stress are unlikely to have been the principal factor driving inter-group differences in cranial proportions. The cranial growth pattern reconstructed from a Medieval Japanese skeletal series showed the greatest magnitude of difference from those reconstructed for other time periods. Unlike in the other groups, there was no marked decline of cephalic index with age for the Medieval series. The unusual trajectory of cranial growth evident in the Medieval sample may result from a high degree of physiological stress due to overall poor nutrition. [ABSTRACT FROM AUTHOR]

The variation among domestic dog breeds offers a unique opportunity to study large-scale diversification by microevolutionary mechanisms. We use geometric morphometrics to quantify the diversity of skull shape in 106 breeds of domestic dog, in three wild canid species, and across the order Carnivora. The amount of shape variation among domestic dogs far exceeds that in wild species, and it is comparable to the disparity throughout the Carnivora. The greatest shape distances between dog breeds clearly surpass the maximum divergence between species in the Carnivora. Moreover, domestic dogs occupy a range of novel shapes outside the domain of wild carnivorans. The disparity among companion dogs substantially exceeds that of other classes of breeds, suggesting that relaxed functional demands facilitated diversification. Much of the diversity of dog skull shapes stems from variation between short and elongate skulls and from modularity of the face versus that of the neurocranium. These patterns of integration and modularity apply to variation among individuals and breeds, but they also apply to fluctuating asymmetry, indicating they have a shared developmental basis. These patterns of variation are also found for the wolf and across the Carnivora, suggesting that they existed before the domestication of dogs and are not a result of selective breeding. [ABSTRACT FROM AUTHOR]

Background: In mammals, new neurons are added to the olfactory bulb (OB) throughout life. Most of these new neurons, granule and periglomerular cells originate from the subventricular zone (SVZ) lining the lateral ventricles and migrate via the rostral migratory stream toward the OB. Thousands of new neurons appear each day, but the function of this ongoing neurogenesis remains unclear. Methodology/Principal Findings: In this study, we irradiated adult mice to impair constitutive OB neurogenesis, and explored the functional impacts of this irradiation on the sense of smell. We found that focal irradiation of the SVZ greatly decreased the rate of production of new OB neurons, leaving other brain areas intact. This effect persisted for up to seven months after exposure to 15 Gray. Despite this robust impairment, the thresholds for detecting pure odorant molecules and short-term olfactory memory were not affected by irradiation. Similarly, the ability to distinguish between odorant molecules and the odorant-guided social behavior of irradiated mice were not affected by the decrease in the number of new neurons. Only long-term olfactory memory was found to be sensitive to SVZ irradiation. Conclusion/Significance: These findings suggest that the continuous production of adult-generated neurons is involved in consolidating or restituting long-lasting olfactory traces. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Odontología Universidad de Antioquia is the property of Universidad de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Syngnathid fishes (seahorses, pipefish, and sea dragons) possess a highly modified cranium characterized by a long and tubular snout with minute jaws at its end. Previous studies indicated that these species are extremely fast suction feeders with their feeding strike characterized by a rapid elevation of the head accompanied by rotation of the hyoid. A planar four-bar model is proposed to explain the coupled motion of the neurocranium and the hyoid. Because neurocranial elevation as well as hyoid rotation are crucial for the feeding mechanism in previously studied Syngnathidae, a detailed evaluation of this model is needed. In this study, we present kinematic data of the feeding strike in the seahorse Hippocampus reidi. We combined these data with a detailed morphological analysis of the important linkages and joints involved in rotation of the neurocranium and the hyoid, and we compared the kinematic measurements with output of a theoretical four-bar model. The kinematic analysis shows that neurocranial rotation never preceded hyoid rotation, thus indicating that hyoid rotation triggers the explosive feeding strike. Our data suggest that while neurocranium and hyoid initially (first 1.5 ms) behave as predicted by the four-bar model, eventually, the hyoid rotation is underestimated by the model. Shortening, or a posterior displacement of the sternohyoid muscle (of which the posterior end is confluent with the hypaxial muscles in H. reidi), probably explains the discrepancy between the model and our kinematic measurements. As a result, while four-bar modeling indicates a clear coupling between hyoid rotation and neurocranial elevation, the detailed morphological determination of the linkages and joints of this four-bar model remain crucial in order to fully understand this mechanism in seahorse feeding. [ABSTRACT FROM AUTHOR]

New data are presented on the neurocranial complex (endocranium plus intimately associated bones of the palate) of the Late Devonian (Famennian) ‘rhynchodipterid’ lungfish Soederberghia groenlandica from the Aina Dal Formation (Celsius Bjerg Group) of East Greenland. Only the otic and occipital regions of the braincase are ossified in Soederberghia. The neurocranium of this genus shares a series of derived features with ‘ Griphognathus’ whitei, including a cranial centrum, fenestrate lateral cristae, and gutters on the ventral surface of the parasphenoid interpreted as accommodating the lateral dorsal aortae. The interrelationships of early lungfishes have been the subject of considerable disagreement. New data from Soederberghia are coupled with a data set focused on the character-rich neurocranial complex in order to examine the systematic utility of this underexploited morphological system. Different methods of phylogenetic inference (maximum parsimony, Bayesian) return broadly consistent results. The Early to Middle Devonian forms Dipnorhynchus, Stomiahykus and Uranolophus are placed among the most basal of lungfishes. ‘Holodontids’ plus ‘rhynchodipterids’ (comprising Griphognathus and Soederberghia) occupy an apical position, and are separated from the earliest lungfishes by a paraphyletic assemblage of taxa generally identified as ‘chirodipterids’ and ‘dipterids.’ This finds broad agreement with the results of previous cladistic studies focused on non-neurocranial data sets, but diverges from functional-adaptive scenarios that posit three lineages of early lungfishes based on aspects of the dentition. As currently defined, both ‘chirodipterids’ and the genus Chirodipterus are heterogeneous assemblages; this analysis fails to find support for the monophyly of either. While this study indicates that Griphognathus is probably paraphyletic, it nevertheless supports a close relationship between the nominal species of this genus and Soederberghia. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151, 115–171. [ABSTRACT FROM AUTHOR]

The sample of South African early to mid-Holocene Later Stone Age(LSA) human crania is small and quite fragmentary, limiting our knowledge of human craniofacial morphology for this period. Previous limited analyses have described the morphology displayed by these early crania as a combination of Khoesan and non-Khoesan traits. Although essentially Khoesan-like in terms of facial morphology, their overall large size and robust neurocranial structure were regarded as atypical of Khoesan craniofacial morphology, leading to questions about the role of these early populations in the ancestry of recent Khoesan populations. Here we provide a quantitative analysis in which we compare five well-preserved pre-5000 BP LSA crania with (i) a large sample of post-5000 BP LSA Khoesan crania; and (ii) a sample of crania from recent South African Bantu-speakers. We show that these pre-5000 BP crania fall comfortably within the range of variation observed for the post-5000 BP Khoesan sample, in terms of both size and shape, suggesting that distinctive Khoesan craniofacial morphology was already present in South African LSA populations by the first half of the Holocene. [ABSTRACT FROM AUTHOR]

Only a single patient with 3-hydroxyisobutyryl-CoA hydrolase deficiency has been described in the literature, and the molecular basis of this inborn error of valine catabolism has remained unknown until now. Here, we present a second patient with 3-hydroxyisobutyryl-CoA hydrolase deficiency, who was identified through blood spot acylcarnitine analysis showing persistently increased levels of hydroxy-C4-carnitine. Both patients manifested hypotonia, poor feeding, motor delay, and subsequent neurological regression in infancy. Additional features in the newly identified patient included episodes of ketoacidosis and Leigh-like changes in the basal ganglia on a magnetic resonance imaging scan. In cultured skin fibroblasts from both patients, the 3-hydroxyisobutyryl-CoA hydrolase activity was deficient, and virtually no 3-hydroxyisobutyryl-CoA hydrolase protein could be detected by western blotting. Molecular analysis in both patients uncovered mutations in the HIBCH gene, including one missense mutation in a conserved part of the protein and two mutations affecting splicing. A carefully interpreted acylcarnitine profile will allow more patients with 3-hydroxyisobutyryl-CoA hydrolase deficiency to be diagnosed. [ABSTRACT FROM AUTHOR]

The process of eye migration in bilaterally symmetrical flatfish larvae starts with asymmetrical growth of the dorsomedial parts of the ethmoid plate together with the frontal bones, structures initially found in a symmetrical position between the eyes. The movement of these structures in the future ocular direction exerts a stretch on the fibroblasts in the connective tissue found between the moving structures and the eye that is to migrate. Secondarily, a dense cell population of fibroblasts ventral to the eye starts to proliferate, possibly cued by the pulling forces exerted by the eye. The increased growth ventral to the eye pushes the eye dorsally. Osteoblasts are deposited in the dense cell layer, forming the dermal part of the lateral ethmoid, and at full eye migration this will cover the area vacated by the migrated eye. When the migrating eye catches up with the previous migrated dermal bones, the frontals, these bones will be remodelled to accommodate the eye. Our findings suggest that a combination of extremely localized signals and more distant factors may impinge upon the outcome of the tissue remodelling. Early normal asymmetry of signalling factors may cascade on a series of events. [ABSTRACT FROM AUTHOR]

This study describes the mechanical role that cranial sutures play in fish during feeding. The long-term goal of our work is to establish relationships between suture form and function, so that functional inferences can be made from suture morphology in fossil taxa. To this end, strain gauges were surgically implanted across selected sutures in the skull roof of four individuals of Polypterus endlicherii. After surgery, bone and suture strains during feeding were recorded along with high-speed video of the feeding events. Each trial was designated as a suction feeding or biting on prey trial, and neurocranial elevation, hyoid position and gape were quantified to aid in interpreting the strain data. The strains due to suction feeding are different from those observed during biting. Suction feeding results in a fairly stereotyped strain pattern, with the interfrontal and frontoparietal sutures experiencing tension, while the interparietai suture is compressed. Biting causes much more variable strain patterns. However, both suction and biting result in compression in the back of the skull, and tension between the frontals. Peak strains, and the time at which they occur in the feeding cycle, were compared between suction and biting. In general, peak suture strains are higher during suction than during biting, but not all of these differences are significant. Peak suture and bone strains occur at or near maximum gape during both suction and biting, suggesting that these strains are caused by muscle contraction involved in mouth opening and closing. Micro-computed tomography (microCT) scans of the experimental specimens indicate that the interfrontal and frontoparietal sutures, typically loaded in tension, are less interdigitated in cross section than the interparietal suture, which experiences compression. This is consistent with published correlations of suture form and function in mammals, where interdigitated sutures indicate compression and lack of interdigitation is associated with tension. [ABSTRACT FROM AUTHOR]

Comparative morphological studies of the earliest human skeletons of the New World have shown that, whereas late prehistoric, recent, and present Native Americans tend to exhibit a cranial morphology similar to late and modern Northern Asians (short and wide neurocrania; high, orthognatic and broad faces; and relatively high and narrow orbits and noses), the earliest South Americans tend to be more similar to present Australians, Melanesians, and Sub-Saharan Africans (narrow and long neurocrania; prognatic, low faces; and relatively low and broad orbits and noses). However, most of the previous studies of early American human remains were based on small cranial samples. Herein we compare the largest sample of early American skulls ever studied (81 skulls of the Lagoa Santa region) with worldwide data sets representing global morphological variation in humans, through three different multivariate analyses. The results obtained from all multivariate analyses confirm a close morphological affinity between South- American Paleoindians and extant Australo-Melanesians groups, supporting the hypothesis that two distinct biological populations could have colonized the New World in the Pleistocene/Holocene transition. [ABSTRACT FROM AUTHOR]

The middle meningeal vascular network leaves its traces on the endocranial surface because of the tight relationship between neurocranial development and brain growth. Analysing the endocast of fossil specimens, it is therefore possible to describe the morphology of these structures, leading inferences on the cerebral physiology and metabolism in extinct human groups. In this paper, general features of the meningeal vascular traces are described for specimens included in the Homo erectus , Homo neanderthalensis , and Homo sapiens hypodigms. The complexity of the arterial network is quantified by its fractal dimension, calculated through the box-counting method. Modern humans show significant differences from the other two taxa because of the anterior vascular dominance and the larger fractal dimension. Neither the fractal dimension nor the anterior development are merely associated with cranial size increase. Considering the differences between Neanderthals and modern humans, these results may be interpreted in terms of phylogeny, cerebral functions, or cranial structural network. [ABSTRACT FROM AUTHOR]

A series of 20 craniodental measurements was obtained for two sister taxa: Nycticebus coucang (common slow loris) and N. pygmaeus (pygmy slow loris). Multivariate analysis of variance was performed with adult data to describe patterns of subspecific and specific variation in this genus. The geometric mean of adult cranial dimensions was compared to field data on latitudinal coordinates for available specimens to investigate if size variation in Nycticebus is clinal in nature. Ontogenetic series for larger-bodied N. coucang and smaller-bodied N. pygmaeus were compared to test the hypothesis that species and subspecific variation in skull form results from the differential extension of common patterns of relative growth. A MANOVA provides independent support of Groves's [pp. 44–53 in Proceedings of the Third International Congress on Primatology, Vol. 1 (Basel: S. Karger), 1971] classification of Nycticebus into two species, with four subspecies in the common slow loris and one form of the pygmy slow loris. Within N. coucang, cranial proportions for all four subspecies are ontogenetically scaled, and size differentiation is mainly clinal (Bergmann's Rule). N. c. bengalensis represents the most northerly disposed and the largest form. N. c. javanicus represents the next-largest form and is located in a southerly direction the next-farthest away from the equator. N. c. coucang and N. c. menagensis are both equatorial; however, the latter subspecies is the smallest. A genetic basis for some of the taxonomic variation between N. c. coucang and N. c. menagensis is supported by such nonclinal variation in body size. Variation in the presence/absence of I[sup 2] is not size-related but rather tracks geographic proximity and isolating factors which predate the most recent inundation of the Sunda Shelf. Although they inhabit a nonequatorial environment, pygmy slow lorises are the smallest of all Nycticebus. As N. pygmaeus is sympatric with N. c. bengalensis, the largest slow loris, it appears that the evolution of its smaller body size represents a case of character displacement. Unlike N. coucang, skull size becomes significantly smaller in more northern N. pygmaeus. This may also reflect character displacement between sympatric sister taxa underlain by a cline-dependent ecological factor which is marked in more northerly latitudes. On the other hand, the negative correlation between body size and latitude in N. pygmaeus could be due to the influence of nonprimate fauna, such as predators, which themselves evince a similar clinal pattern. Analyses of relative growth indicate that skull proportions in the two species of Nycticebus are ontogenetically scaled in two-thirds of the cases. All but one of the seven comparisons (interorbital breadth) which do not indicate ontogenetic scaling represent part of the masticatory complex. This likely reflects a reorganization of N. pygmaeus maxillomandibular proportions linked to smaller size and changes in diet. Am. J. Primatol. 45:225–243, 1998. © 1998 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Artificial reshaping of the cranial vault has been practiced by many human groups and provides a natural experiment in which the relationships of neurocranial, cranial base, and facial growth can be investigated. We test the hypothesis that fronto-occipital artificial reshaping of the neurocranial vault results in specific changes in the cranial base and face. Fronto-occipital reshaping results from the application of pads or a cradle board which constrains cranial vault growth, limiting growth between the frontal and occipital and allowing compensatory growth of the parietals in a mediolateral direction. Two skeletal series including both normal and artificially modified crania are analyzed, a prehistoric Peruvian Ancon sample (47 normal, 64 modified crania) and a Songish Indian sample from British Columbia (6 normal, 4 modified). Three-dimensional coordinates of 53 landmarks were measured with a diagraph and used to form 9 finite elements as a prelude to finite element scaling analysis. Finite element scaling was used to compare average normal and modified crania and the results were evaluated for statistical significance using a bootstrap test. Fronto-occipitally reshaped Ancon crania are significantly different from normal in the vault, cranial base, and face. The vault is compressed along an anterior-superior to posterior-inferior axis and expanded along a mediolateral axis in modified individuals. The cranial base is wider and shallower in the modified crania in the face is foreshortened and wider with the anterior orbital rim moving inferior and posterior towards the cranial base. The Songish crania display a different modification of the vault and face, indicating that important differences may exist in the morphological effects of fronto-occipital reshaping from one group to another. © 1992 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

This article presents information on the development of the chondrocranium of ascaphus truei stejneger with special reference to the relations of the palatoquadrate to the neurocranium. The relations of the mandibular and hyoid arches to the neurocranium constitute one of the major problems arising from a study of the cranial anatomy of vertebrates, being intimately connected with the theories concerning the phylogeny of this subphylum. Most of the specimens of Ascaphus used for this investigation were collected from Mt. Rose, Big Log Ranger Station, McTaggert Creek, Laundry Creek, Antter Creek and Mt. Steel in Washington State, and from Wilametta and Portland, Oregon.

The neurocranium changes rapidly in early childhood to accommodate the growing brain. Developmental disorders and environmental factors such as sleep position may lead to abnormal neurocranial maturation. Therefore, it is important to understand how this structure develops, in order to provide a baseline for early detection of anomalies. However, its anatomy has not yet been well studied in early childhood due to the lack of available imaging databases. In hospitals, CT is typically used to image the neurocranium when a pathology is suspected, but the presence of ionizing radiation makes it harder to construct databases of healthy subjects. In this study, instead, we use a dataset of MRI data from healthy normal children in the age range of 6 months to 36 months to study the development of the neurocranium. After extracting its outline from the MRI data, we used a conformal geometry-based analysis pipeline to detect local thickness growth throughout this age span. These changes will help us understand cranial bone development with respect to the brain, as well as detect abnormal variations, which will in turn inform better treatment strategies for implicated disorders. [ABSTRACT FROM AUTHOR]

Reports on a case of nasal septum fracture after a complementary and alternative medicine procedure called neurocranial restructuring that was used to treat a patient with chronic sinusitis. Evaluation of the patient; Experience of the patient during the NCR procedure.

We report an unusual case of a 10-year-old girl with neurocryptococcosis that was diagnosed only after histological examination of the cyst fluid obtained at surgery. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor of the "Archives of Otolaryngology--Head & Neck Surgery" about neurocranial restructuring and homeopathy.

This study was conducted using 60 skulls from equal-sized samples of adult male rats from the Birmingham, Wistar, and Sprague-Dawley inbred strains. With the use of a measuring microscope nine dimensions were determined from each skull. The results indicated that when the skull was considered as a whole, significant contrasts between the three inbred strains were apparent. Furthermore, the discrimination between the three inbred strains were apparent. These contrasting patterns were confirmed from the generalized distance matrix.