The morphology and biomechanics of infant crania undergo significant changes between the pre- and post-weaning phases due to increasing loading of the masticatory system. The aims of this study were to characterize the changes in muscle forces, bite forces and the pattern of mechanical strain and stress arising from the aforementioned forces across crania in the first 48 months of life using imaging and finite element methods. A total of 51 head computed tomography scans of normal individuals were collected and analysed from a larger database of 217 individuals. The estimated mean muscle forces of temporalis, masseter and medial pterygoid increase from 30.9 to 87.0 N, 25.6 to 69.6 N and 23.1 to 58.9 N, respectively (0–48 months). Maximum bite force increases from 90.5 to 184.2 N (3–48 months). There is a change in the pattern of strain and stress from the calvaria to the face during postnatal development. Overall, this study highlights the changes in the mechanics of the craniofacial system during normal development. It further raises questions as to how and what level of changes in the mechanical forces during the development can alter the morphology of the craniofacial system.

Our fundamental understanding of the physico-mechanical forces that drive the size and shape changes of the cranium during ontogeny are limited. Biomechanical models based on finite element method present a huge opportunity to address this critical gap in our knowledge. Here, we describe a validated computational framework to predict normal craniofacial growth. Our results demonstrated that this approach is capable of predicting the growth of calvaria, face, and skull base. We highlighted the crucial role of skull base in antero-posterior growth of the face and also demonstrated the contribution of the maxillary expansion to the dorsoventral growth of the face and its interplay with the orbits. These findings highlight the importance of physical interactions of different components of the craniofacial system. The computational framework described here serves as a powerful tool to study fundamental questions in developmental biology and to advance treatment of conditions affecting the craniofacial system such as craniosynostosis.

The use of non‐destructive approaches for digital acquisition (e.g. computerised tomography—CT) allows detailed qualitative and quantitative study of internal structures of skeletal material. Here, we present a new R‐based software tool, Icex, applicable to the study of the sizes and shapes of skeletal cavities and fossae in 3D digital images. Traditional methods of volume extraction involve the manual labelling (i.e. segmentation) of the areas of interest on each section of the image stack. This is time‐consuming, error‐prone and challenging to apply to complex cavities. Icex facilitates rapid quantification of such structures. We describe and detail its application to the isolation and calculation of volumes of various cranial cavities. The R tool is used here to automatically extract the orbital volumes, the paranasal sinuses, the nasal cavity and the upper oral volumes, based on the coordinates of 18 cranial anatomical points used to define their limits, from 3D cranial surface meshes obtained by segmenting CT scans. Icex includes an algorithm (Icv) for the calculation of volumes by defining a 3D convex hull of the extracted cavity. We demonstrate the use of Icex on an ontogenetic sample (0–19 years) of modern humans and on the fossil hominin crania Kabwe (Broken Hill) 1, Gibraltar (Forbes' Quarry) and Guattari 1. We also test the tool on three species of non‐human primates. In the modern human subsample, Icex allowed us to perform a preliminary analysis on the absolute and relative expansion of cranial sinuses and pneumatisations during growth. The performance of Icex, applied to diverse crania, shows the potential for an extensive evaluation of the developmental and/or evolutionary significance of hollow cranial structures. Furthermore, being open source, Icex is a fully customisable tool, easily applicable to other taxa and skeletal regions.

Background In percutaneous coronary intervention (PCI), the ability to predict post-PCI fractional flow reserve (FFR) and stented vessel informs procedural planning. However, highly precise and effective methods to quantitatively simulate coronary intervention are lacking. This study developed and validated a virtual coronary intervention (VCI) technique for non-invasive physiological and anatomical assessment of PCI. Methods In this study, patients with substantial lesions (pre-PCI CT-FFR of less than 0.80) were enrolled. VCI framework was used to predict vessel reshape and post-PCI CT-FFR. The accuracy of predicted post-VCI CT-FFR, luminal cross-sectional area (CSA) and centreline curvature was validated with post-PCI computed tomography (CT) angiography datasets. Results Overall, 30 patients are initially screened; 21 meet the inclusion criteria, and 9 patients (9 vessels) are included in the final analysis. The average PCI-simulation time is 24.92 ± 1.00 s on a single processor. The calculated post-PCI CT-FFR is 0.92 ± 0.09, whereas the predicted post-VCI CT-FFR is 0.90 ± 0.08 (mean difference: −0.02 ± 0.05 FFR units; limits of agreement: −0.08 to 0.05). Morphologically, the predicted CSA is 16.36 ± 4.41 mm² and the post-CSA is 17.91 ± 4.84 mm² (mean difference: −1.55 ± 1.89 mm²; limits of agreement: −5.22 to 2.12). The predicted centreline curvature across the stented segment (including ~2 mm proximal and distal margins) is 0.15 ± 0.04 mm⁻¹, while the post-PCI centreline curvature is 0.17 ± 0.03 mm⁻¹ (mean difference: −0.02 ± 0.06 mm⁻¹; limits of agreement: −0.12 to 0.09). Conclusions The proposed VCI technique achieves non-invasive pre-procedural anatomical and physiological assessment of coronary intervention. The proposed model has the potential to optimize PCI pre-procedural planning and improve the safety and efficiency of PCI.

The Yucatan miniature pig has become a preferred model for craniofacial research due to its anatomical and physiological similarities to humans. However, the factors driving midfacial hypoplasia in Yucatans during postnatal ontogeny remain unclear. This study characterized postnatal skull growth and development, and morphological variations in Yucatan and standard (domestic) pigs, with a focus on the role of joint maturation in resulting craniofacial dysmorphology. Forty available head specimens (Yucatan: n = 20, 0–12 months; standard: n = 20, 0–8 months) were analysed using multidimensional craniometric measurements and geometric morphometrics. Results show that both breeds follow an allometric growth trajectory, largely driven by the expansion of craniofacial organs and capsules. At birth, skull morphology was similar between breeds; however, Yucatans developed a shorter face and more compact neurocranium, while maintaining a nearly identical mandibular shape to standard pigs. Over the first three months, Yucatans exhibit delayed calvarial suture fusion compared with standard pigs, while skull base synchondroses remain patent in both breeds. These findings reflect the scaling relations between breeds and highlight differential growth patterns of the midface, neurocranium and mandible in Yucatans, emphasizing their interactions with organ development, cavity expansion and joint maturation, offering insights into the mechanisms driving craniofacial diversification in pig models.

Craniosynostosis is a congenital condition characterized by the premature fusion of the craniofacial sutures. The Crouzon mouse (Fgfr2cC342Y/+) is a well-established model of this condition which shows premature fusion of the coronal suture. Our group has recently shown that postnatal, cyclic loading can potentially rescue the coronal suture and normalize skull morphology in Crouzon mice. This study aimed to investigate the underlying biological mechanism of the treatment. Wild-type (WT) and Crouzon (MUT) mice underwent in vivo loading sessions. Loading did not significantly affect skull shape. The patency across the coronal suture did not change between treated and untreated MUT animals. Orientation and coherence of the coronal suture collagen fibres were statistically different when comparing WT untreated with MUT untreated and WT treated with MUT treated. Treatment increases the number of proliferative cells in both the WT and MUT sutures compared to their untreated counterparts. The mechanobiological mechanisms driving the differences need further investigation into molecular mechanotransduction pathways. Understanding the biological principles affected during bone loading, a more refined cyclical bone loading protocol can be developed and refined for potential clinical use.