Variation in enamel and dentine mineral concentration and density in primate molars.

Objective: Variation in enamel and dentine mineral concentration and total effective density can be reliably collected using Micro-CT scans. Both variables are suggested to reflect mechanical properties such as hardness and elastic modulus in dental tissues, meaning Micro-CT methods allow relative composition and mechanical properties to be collected non-destructively.

Design: 16 lower molars from 16 Catarrhine primates were Micro-CT scanned alongside hydroxyapatite phantoms using standardized settings and methods to calculate mineral concentration and total effective density.

3D-localisation of cochlear implant electrode contacts in relation to anatomical structures from in vivo cone-beam computed tomography.

Positioning of the cochlear implant (CI) electrode in relation to the anatomical structures is a key factor for the hearing outcome and the preservation of residual hearing after cochlear implantation. Determining the exact electrode's location is therefore expected to play an important role in optimisation of the electrode design, the surgical techniques and the post-operative device fitting. The aim of this study is the development and validation of a robust and efficient computerised algorithm for three-dimensional (3D) localisation of the CI-electrode contacts with respect to the relevant cochlear structures, such as the basilar membrane and the modiolus, from modern clinical in vivo cone-beam computed tomography (CBCT).

Growth of Neanderthal infants from Krapina (120-130 ka), Croatia.

Modern humans have a slow and extended period of childhood growth, but to what extent this ontogenetic pathway was present in Neanderthals is debated. Dental development, linked to the duration of somatic growth across modern primates, is the main source for information about growth and development in a variety of fossil primates, including humans. Studies of Neanderthal permanent teeth report a pace of development either similar to recent humans or relatively accelerated.

Arothron: An R package for geometric morphometric methods and virtual anthropology applications.

Objectives: The statistical analysis of fossil remains is essential to understand the evolution of the genus Homo. Unfortunately, the human fossil record is straight away scarce and plagued with severe loss of information caused by taphonomic processes. The recently developed field of Virtual Anthropology helps to ameliorate this situation by using digital techniques to restore damaged and incomplete fossils.

Novel strategies for the characterization of cancellous bone morphology: Virtual isolation and analysis.

Objectives: The advent of micro-computed tomography (μCT) made cancellous bone more accessible than ever before. Nevertheless, the characterization of cancellous bone is made difficult by its inherent complexity and the difficulties in defining homology across datasets. Here we propose novel virtual methodological approaches to overcome those issues and complement existing methods.

Contamination inside CT gantry in the SARS-CoV-2 era.

We investigated whether the internal gantry components of our computed tomography (CT) scanner contain severe acute respiratory syndrome 2 (SARS-CoV-2) ribonucleic acid (RNA), bacterial or fungal agents. From 1 to 27 March 2020, we performed 180 examinations of patients with confirmed SARS-CoV-2 infection using a dedicated CT scanner. On 27 March 2020, this CT gantry was opened and sampled in each of the following components: (a) gantry case; (b) inward airflow filter; (c) gantry motor; (d) x-ray tube; (e) outflow fan; (f) fan grid; (g) detectors; and (h) x-ray tube filter.

Locomotion, posture, and the foramen magnum in primates: Reliability of indices and insights into hominin bipedalism.

The position (FMP) and orientation (FMO) of the foramen magnum have been used as proxies for locomotion and posture in extant and extinct primates. Several indices have been designed to quantify FMP and FMO but their application has led to conflicting results. Here, we test six widely used indices and two approaches (univariate and multivariate) for their capability to discriminate between postural and locomotor types in extant primates and fossil hominins.

Evaluation of novel coronavirus disease (COVID-19) using quantitative lung CT and clinical data: prediction of short-term outcome.

Background: Computed tomography (CT) enables quantification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, helping in outcome prediction.

Methods: From 1 to 22 March 2020, patients with pneumonia symptoms, positive lung CT scan, and confirmed SARS-CoV-2 on reverse transcription-polymerase chain reaction (RT-PCR) were consecutively enrolled. Clinical data was collected.

Endomaker, a new algorithm for fully automatic extraction of cranial endocasts and the calculation of their volumes.

Objectives: Reproducing cranial endocasts is a major goal of researchers interested in vertebrate brain evolution. We present a new R software, named endomaker, which allows the automatic extraction of endocasts from skull meshes along with the calculation of its volume.

Materials And Methods: We applied endomaker on non-primate and primate skulls including the Australopithecus africanus specimen Sts-5.

Three-Dimensional Visualisation of Skeletal Cavities.

Bones contain spaces within them. The extraction and the analysis of those cavities are crucial in the study of bone tissue function and can inform about pathologies or past traumatic events. The use of medical imaging techniques allows a non-invasive visualisation of skeletal cavities opening a new frontier in medical inspection and diagnosis.

A New Tool for Digital Alignment in Virtual Anthropology.

The study of the fossil record is fundamental to understand the evolution of traits. Because fossil remains are often fragmented and/or deformed by taphonomic processes, a preliminary realignment of their constituent parts is often necessary to properly interpret their shapes. In virtual anthropology, these procedures are carried out using digital models of the remains.

The functional significance of dental and mandibular reduction in Homo: A catarrhine perspective.

The reduction in dental size and mandibular robusticity is regarded as a major trend in human evolution, traditionally considered the result of the peculiar extra-oral food processing skills of Homo. The use of stone tools and fire would have allowed our ancestors to chew softer food in smaller bite size, thus relaxing the selective pressures to keep a large dentition and a robust lower jaw. This perspective assumes that differences in dental size and mandibular robusticity in hominins represent functional dissimilarities.

Neuromandibular integration in humans and chimpanzees: Implications for dental and mandibular reduction in Homo.

Objectives: Although the evolution of the hominin masticatory apparatus has been linked to diet and food processing, the physical connection between neurocranium and lower jaw suggests a role of encephalization in the trend of dental and mandibular reduction. Here, the hypothesis that tooth size and mandibular robusticity are influenced by morphological changes in the neurocranium was tested.

Materials And Methods: Three-dimensional landmarks, alveolar lengths, and mandibular robusticity data were recorded on a sample of chimpanzee and human skulls.

Reproducing the internal and external anatomy of fossil bones: Two new automatic digital tools.

Objectives: We present two new automatic tools, developed under the R environment, to reproduce the internal and external structures of bony elements. The first method, Computer-Aided Laser Scanner Emulator (CA-LSE), provides the reconstruction of the external portions of a 3D mesh by simulating the action of a laser scanner. The second method, Automatic Segmentation Tool for 3D objects (AST-3D), performs the digital reconstruction of anatomical cavities.

Surface smoothing, decimation, and their effects on 3D biological specimens.

Objective: Smoothing and decimation filters are commonly used to restore the realistic appearance of virtual biological specimens, but they can cause a loss of topological information of unknown extent. In this study, we analyzed the effect of smoothing and decimation on a 3D mesh to highlight the consequences of an inappropriate use of these filters.

Materials And Methods: Topological noise was simulated on four anatomical regions of the virtual reconstruction of an orangutan cranium.

The evolution of cranial base and face in Cercopithecoidea and Hominoidea: Modularity and morphological integration.

The evolutionary relationship between the base and face of the cranium is a major topic of interest in primatology. Such areas of the skull possibly respond to different selective pressures. Yet, they are often said to be tightly integrated.