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Introduction: Cephalometry performed on sagittal teleradiographic X-rays is commonly used for the planification of orthognathic procedures. Tomographic imaging techniques (computer tomography or cone-beam computer tomography) are more and more prescribed for the assessment of complex occlusofacial anomalies. In this study, we intended to evaluate if teleradiographic X-rays reconstructed from computer tomography (CT) can be used to trace reliable cephalometric analyses. We assessed the inter- and intra-observer reproducibility of a simplified Delaire analysis (Top 12), one of the numerous common cephalometric analyses, performed with the Delaire Evolution software on three sets of X-rays: (1) conventional cephalometric X-rays, (2) 2D reconstructions obtained from the CT scans of the same patients and (3) 2D reconstructions obtained from CT scans of dry skulls without a cervical spine (anthropological material). Our primary goal was to assess X-rays reconstructed from tomographies as an alternative for conventional cephalometric X-rays. Our secondary goal was to assess whether computerized cephalometric analysis was a reproducible technique, both on clinical and anthropological material., Materials and Methods: We included 10 consecutive adult patients admitted for orthodontic assessment who had benefited from both lateral cephalometric X-rays and from CT-scans. We also included 10 CT-scans from adult dry skulls without a cervical spine, from the collections of the Muséum National d'Histoire Naturelle (Musée de l'Homme, Paris, France). Cephalometric X-rays were reconstructed from CT-scans of both patients and dry skulls using Carestream® (Carestream Health inc., New York, USA). Simplified Delaire analyses (Top12) were conducted by 2 observers using the Delaire Evolution software (JDel, Nantes, France), on the 3 sets of cephalometric X-rays: (1) 10 standard cephalometric X-rays from the orthodontic patients, (2) 10 reconstructed cephalometric X-rays from the CT scans of the orthodontic patients and (3) 10 reconstructed cephalometric X-rays from the CT scans of the dry skulls. A standard statistical assessment of reproducibility was conducted using correlation coefficients., Results: We found good inter- and intra-observer reproducibility for standard cephalometric X-rays and reconstructed cephalometric X-rays (Intraclass Correlation Coeficient > 0.75). We did not find any difference for angle measures between the standard cephalometric X-rays and the reconstructed cephalometric X-rays for the group of orthodontic patients (P > 0.05). Delaire cephalometric analysis was not reproducible for cephalometric X-rays without a cervical spine, that is for cephalometric X-rays reconstructed from the CT-scans of dry skulls., Discussion: Delaire computerized simplified Top12 analysis was reproducible for lateral cephalometric X-rays and for reconstructions obtained from CT scans with similar angle measures for a given patient. This analysis does not seem to be reliable for dry skulls without upper cervical spine. This study uses the example of one particular computerized cephalometric analysis in order to show that cephalometric analyses can be performed on lateral reconstructed cephalometric X-rays obtained from CT scans., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

This study assessed three-dimensional (3D) photogrammetry as a tool for capturing and quantifying human skull morphology. While virtual reconstruction with 3D surface scanning technology has become an accepted part of the paleoanthropologist's tool kit, recent advances in 3D photogrammetry make it a potential alternative to dedicated surface scanners. The principal advantages of photogrammetry are more rapid raw data collection, simplicity and portability of setup, and reduced equipment costs. We tested the precision and repeatability of 3D photogrammetry by comparing digital models of human crania reconstructed from conventional, 2D digital photographs to those generated using a 3D surface scanner. Overall, the photogrammetry and scanner meshes showed low degrees of deviation from one another. Surface area estimates derived from photogrammetry models tended to be slightly larger. Landmark configurations generally did not cluster together based upon whether the reconstruction was created with photogrammetry or surface scanning technology. Average deviations of landmark coordinates recorded on photogrammetry models were within the generally allowable range of error in osteometry. Thus, while dependent upon the needs of the particular research project, 3D photogrammetry appears to be a suitable, lower-cost alternative to 3D imaging and scanning options., (Copyright © 2014 Wiley Periodicals, Inc.)

In the past, improvements in craniofacial reconstructions (CFR) methodology languished due to the lack of adequate 3D databases that were sufficiently large and appropriate for 3-dimensional shape statistics. In our study, we created the "FACE-R" database from CT records and 3D surface scans of 400 clinical patients from Hungary, providing a significantly larger sample that was available before. The uniqueness of our database is linking of two data types that makes possible to investigate the bone and skin surface of the same individual, in upright position, thus eliminating many of the gravitational effects on the face during CT scanning. We performed a preliminary geometric morphometric (GMM) study using 3D data that produces a general idea of skull and face shape correlations. The vertical position of the tip of the (soft) nose for a skull and landmarks such as rhinion need to be taken into account. Likewise, the anterior nasal spine appears to exert some influence in this regard., (© 2013 American Academy of Forensic Sciences.)

As virtual anthropology is becoming more and more ubiquitous, so are the means to acquire, process and analyze 3D data. Among these means, surface scanners have gained a prominent place for a variety of reasons that make them useful to anthropologists. While surface scanning has several advantages over other 3D devices (digitizers, volume scanners etc.), it does come with one obvious drawback - internal structures remain invisible. Still, surface scanning is emerging as a convenient tool for anthropometric and especially paleoanthropological research. It extends our ability to quantify phenotypic variation, its non-destructive nature contributes to specimen conservation, and it can become an integral part of virtual anthropology, thus doing more than just "scratching the surface".