Atlas rotation and mandibular deviation by Cone Beam CT

Cervical vertebrae and mandible are functionally related and some evidences suggest a strong correlation between their relative position and orientation (Huggare et al., 1996; Nisayif et al., 2005). In this study TC Dental Scan with cone beam technology was used to study the relationship between atlas and mandibular rotation in 205 patients. Using a digitalized images analyser, we calculated the axial rotation of atlas and mandible, measuring the angle with respect to the frontal plane. We found that 80.98% of patients presented the axial rotation of the mandible in the same direction of atlas rotation compared with 19.02% of patients that presented opposite directions. Among the consistent group, 71.08% of patients had a left rotation compared with 28.92% that had a right rotation. Moreover, considering the absolute values of the rotation, we observed that the atlas had a more marked rotation with respect to the mandible and that the values of left rotations were higher with respect to the value recorded for right rotations both for the mandible and atlas measurements. This study represents a starting point to better characterize the relationship between atlas and mandible; further studies are necessary to better understand the importance of this data from a functional and clinical point of view

Peripheral Purinergic Modulation in Pediatric Orofacial Inflammatory Pain Affects Brainstem Nitroxidergic System: A Translational Research

Physiology of orofacial pain pathways embraces primary afferent neurons, pathologic changes in the trigeminal ganglion, brainstem nociceptive neurons, and higher brain function regulating orofacial nociception. The goal of this study was to investigate the nitroxidergic system alteration at brainstem level (spinal trigeminal nucleus), and the role of peripheral P2 purinergic receptors in an experimental mouse model of pediatric inflammatory orofacial pain, to increase knowledge and supply information concerning orofacial pain in children and adolescents, like pediatric dentists and pathologists, as well as oro-maxillo-facial surgeons, may be asked to participate in the treatment of these patients. The experimental animals were treated subcutaneously in the perioral region with pyridoxalphosphate-6-azophenyl-2′,4′-disulphonic acid (PPADS), a P2 receptor antagonist, 30 minutes before formalin injection. The pain-related behavior and the nitroxidergic system alterations in the spinal trigeminal nucleus using immunohistochemistry and western blotting analysis have been evaluated. The local administration of PPADS decreased the face-rubbing activity and the expression of both neuronal and inducible nitric oxide (NO) synthase isoforms in the spinal trigeminal nucleus. These results underline a relationship between orofacial inflammatory pain and nitroxidergic system in the spinal trigeminal nucleus and suggest a role of peripheral P2 receptors in trigeminal pain transmission influencing NO production at central level. In this way, orofacial pain physiology should be elucidated and applied to clinical practice in the futur

Morphometric analysis of Huguier’s canal by Cone Beam CT

The middle ear and the stomatognatic system are closely anatomically and functionally related. The anterior chordal canal of Huguier connects the temporomandibular joint (TMJ) and the middle ear. This canal is formed by the inferior process of tegment tympani and the sphenoid bone and it is located at the medial end of the petrotympanic fissure. To data, few studies aimed to describe Huguier’s canal morphology and its related structures (Toth et al., 2006; Sato et al., 2008; Aristeguieta et al., 2009). The aim of this study is to describe the radiological anatomy of the Huguier’s canal using cone beam CT (CBCT, Scanora 3D, Soredex). We measured 438 Huguier’s canals from 219 human skulls (Section of Anthropology and Ethnology, Museum of Natural History, Florence, Italy). The measurements were made at three levels: 1) near the TMJ (lateral-glenoidal side) that was 1.961 ± 0.472 mm; 2) the narrowest point of the middle area that was 0.494 ± 0.24 mm; 3) near the middle ear (medial, acoustic meatus side) that was 1.085 ± 0.354 mm. 21 on 439 Huguier’s canal (4.79%) were ossificated: 1 only in the medial side, 11 only in the middle area and 9 in all the three levels. Considering the high number of measurements, the values obtained were comparable, suggesting that CBCT can be useful to detect these anatomical details

3D gelatin-chitosan hybrid hydrogels combined with human platelet lysate highly support human mesenchymal stem cell proliferation and osteogenic differentiation

Bone marrow and adipose tissue human mesenchymal stem cells were seeded in highly performing 3D gelatin–chitosan hybrid hydrogels of varying chitosan content in the presence of human platelet lysate and evaluated for their proliferation and osteogenic differentiation. Both bone marrow and adipose tissue human mesenchymal stem cells in gelatin–chitosan hybrid hydrogel 1 (chitosan content 8.1%) or gelatin–chitosan hybrid hydrogel 2 (chitosan 14.9%) showed high levels of viability (80%–90%), and their proliferation and osteogenic differentiation was significantly higher with human platelet lysate compared to fetal bovine serum, particularly in gelatin–chitosan hybrid hydrogel 1. Mineralization was detected early, after 21 days of culture, when human platelet lysate was used in the presence of osteogenic stimuli. Proteomic characterization of human platelet lysate highlighted 59 proteins mainly involved in functions related to cell adhesion, cellular repairing mechanisms, and regulation of cell differentiation. In conclusion, the combination of our gelatin–chitosan hybrid hydrogels with hPL represents a promising strategy for bone regenerative medicine using human mesenchymal stem cells

An internal variable model for plastic remodeling in fibrous materials

We propose a continuum model of fibrous materials that may undergo an internal reorganization, which turns out in a plastic change of the orientation of the fibers, if a threshold is achieved. We find that the remodeling may induce a rich material response. In a traction test, when the threshold condition is reached, we show that the most general transversely isotropic material may evolve in three different ways; in particular, the fibers asymptotically tend (regularly or with jumps): (A) to a given angle; (B) to align perpendicularly with respect to the load direction; (C) to align with the load direction if their initial angle is less than a given value, or perpendicularly, otherwise. We provide analytical solutions for the evolutive homogeneous problem and some numerical results for a non-homogeneous condition. The theory is very general and can find applications in several problems arising in material mechanics

[West Nile virus and myocarditis, a rare event: case report]

: We present a rare case of a 77-year-old Italian woman, admitted to the neurology unit with the diagnosis of West Nile virus encephalitis. Twenty days after the onset of the neurological symptoms, new negative T-waves appeared on the ECG in association with serum elevation of myocardial necrosis enzymes and regional cardiac wall motion abnormalities on echocardiography, so that a coronary angiography was performed. The exam showed significant stenosis on the left circumflex artery, treated with percutaneous coronary intervention. In addition, a cardiovascular magnetic resonance was performed for further investigation: the T2-weighted images revealed edema in the anterior wall and mid-wall late gadolinium enhancement, significant findings of acute myocardial inflammation. Because of the recent diagnosis of West Nile virus encephalitis and the high serum level of specific IgM antibody, the clinical presentation was suggestive of West Nile myocarditis

Modelling compression sensing in ionic polymer metal composites

Ionic Polymer Metal Composites (IPMCs) consist of an ionomeric membrane, including mobile counterions, sandwiched between two thin noble metal electrodes. IPMCs find application as sensors and actuators, where an imposed mechanical loading generates a voltage across the electrodes, and, vice versa, an imposed electric field causes deformation. Here, we present a predictive modelling approach to elucidate the dynamic sensing response of IPMCs subject to a time-varying through-the-thickness compression ("compression sensing"). The model relies on the continuum theory recently developed by Porfiri and co-workers, which couples finite deformations to the modified Poisson-Nernst-Planck (PNP) system governing the IPMC electrochemistry. For the "compression sensing" problem we establish a perturbative closed-form solution along with a Finite Element (FE) solution. The systematic comparison between these two solutions is a central contribution of this study, offering insight on accuracy and mathematical complexity. The method of matched asymptotic expansions is employed to find the analytical solution. To this end, we uncouple the force balance from the modified PNP system and separately linearise the PNP equations in the ionomer bulk and in the boundary layers at the ionomer-electrode interfaces. Comparison with FE results for the fully coupled nonlinear system demonstrates the accuracy of the analytical solution to describe IPMC sensing for moderate deformation levels. We finally demonstrate the potential of the modelling scheme to accurately reproduce experimental results from the literature. The proposed model is expected to aid in the design of IPMC sensors, contribute to an improved understanding of IPMC electrochemomechanical response, and offer insight into the role of nonlinear phenomena across mechanics and electrochemistry