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Minimally invasive approaches for aortic valve replacement are now at the forefront of pathological aortic valve treatment. New trials show comparability of these devices to existing therapies, not only in high‐risk surgical cohorts but also in low‐risk and intermediate‐risk cohorts. This review provides vital clinical and anatomical background to aortic valvular disease treatment guidelines, while also providing an update on transcatheter aortic valve implantation (TAVI) devices in Europe, their interventional trials and associated complications. [ABSTRACT FROM AUTHOR]

Lower jaw (mandible) fractures significantly impact patient health and well‐being due to pain and difficulty eating, but the best technique for repairing the most common subtype—angle fractures—and rehabilitating mastication is unknown. Our study is the first to use realistic in silico simulation of chewing to quantify the effects of Champy and biplanar techniques of angle fracture fixation. We show that more rigid, biplanar fixation results in lower strain magnitudes in the miniplates, the bone around the screws, and in the fracture zone, and that the mandibular strain regime approximates the unfractured condition. Importantly, the strain regime in the fracture zone is affected by chewing laterality, suggesting that both fixation type and the patient's post‐fixation masticatory pattern—ipsi‐ or contralateral to the fracture— impact the bone healing environment. Our study calls for further investigation of the impact of fixation technique on chewing behavior. Research that combines in vivo and in silico approaches can link jaw mechanics to bone healing and yield more definitive recommendations for fixation, hardware, and postoperative rehabilitation to improve outcomes. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Snake fangs are an iconic exemplar of a complex adaptation, but despite striking developmental and morphological similarities, they probably evolved independently in several lineages of venomous snakes. How snakes could, uniquely among vertebrates, repeatedly evolve their complex venom delivery apparatus is an intriguing question. Here we shed light on the repeated evolution of snake venom fangs using histology, high-resolution computed tomography (microCT) and biomechanical modelling. Our examination of venomous and non-venomous species reveals that most snakes have dentine infoldings at the bases of their teeth, known as plicidentine, and that in venomous species, one of these infoldings was repurposed to form a longitudinal groove for venom delivery. Like plicidentine, venom grooves originate from infoldings of the developing dental epithelium prior to the formation of the tooth hard tissues. Derivation of the venom groove from a large plicidentine fold that develops early in tooth ontogeny reveals how snake venom fangs could originate repeatedly through the co-option of a pre-existing dental feature even without close association to a venom duct. We also show that, contrary to previous assumptions, dentine infoldings do not improve compression or bending resistance of snake teeth during biting; plicidentine may instead have a role in tooth attachment.