NHS orthodontic services in Wales: orthodontic workforce distribution and primary care commissioned activity in 2021.

Objectives 1) To ascertain the volume of primary care orthodontic activity commissioned within Wales and compare this to the 12-year-old population; and 2) To ascertain the orthodontic workforce undertaking NHS orthodontic provision within Wales and their distribution.Methods Information was gathered between September and November 2021 from multiple sources within Wales, including: Freedom of Information requests; Welsh Government statistics; orthodontic professional networks; orthodontic provider websites; health boards (HBs); and directors of primary care/contracting/commissioning.Results The HBs had varying levels of orthodontic need and commissioned activity with a significant amount of cross border activity in South Wales. Overall, it indicated that Wales was only commissioning orthodontic activity to meet 76% of the annual orthodontic need. Overall, 97.9% of commissioned primary care orthodontic activity was being used to provide treatment for 9,500 patients per year. Furthermore, 112 GDC-registered clinicians provide NHS orthodontic care within Wales - 52 orthodontic specialists; 32 orthodontic therapists; 24 DwSIs; and 4 orthodontic trainees (StR 1-3). NHS orthodontic care is provided at 47 sites within Wales - 32 sites in the GDS/Specialist Practice, 6 sites within the CDS and 9 secondary care settings.Conclusions NHS commissioned primary care orthodontic activity within Wales is 76% of the potential orthodontic annual need. Primary care orthodontic services are efficient with 97.9% of commissioned activity being used to provide treatment. In total, 112 GDC-registered clinicians provide NHS orthodontic care across 47 sites within Wales, with 29.5% of clinicians working at multiple sites. The distribution of the orthodontic providers is predominately in areas of high population density, resulting in some rural communities being a significant distance from any orthodontic provider.

Apical stress fibers enable a scaling between cell mechanical response and area in epithelial tissue.

Biological systems tailor their properties and behavior to their size throughout development and in numerous aspects of physiology. However, such size scaling remains poorly understood as it applies to cell mechanics and mechanosensing. By examining how the Drosophila pupal dorsal thorax epithelium responds to morphogenetic forces, we found that the number of apical stress fibers (aSFs) anchored to adherens junctions scales with cell apical area to limit larger cell elongation under mechanical stress. aSFs cluster Hippo pathway components, thereby scaling Hippo signaling and proliferation with area. This scaling is promoted by tricellular junctions mediating an increase in aSF nucleation rate and lifetime in larger cells. Development, homeostasis, and repair entail epithelial cell size changes driven by mechanical forces; our work highlights how, in turn, mechanosensitivity scales with cell size.

Vertex stability and topological transitions in vertex models of foams and epithelia.

In computer simulations of dry foams and of epithelial tissues, vertex models are often used to describe the shape and motion of individual cells. Although these models have been widely adopted, relatively little is known about their basic theoretical properties. For example, while fourfold vertices in real foams are always unstable, it remains unclear whether a simplified vertex model description has the same behavior. Here, we study vertex stability and the dynamics of T1 topological transitions in vertex models. We show that, when all edges have the same tension, stationary fourfold vertices in these models do indeed always break up. In contrast, when tensions are allowed to depend on edge orientation, fourfold vertices can become stable, as is observed in some biological systems. More generally, our formulation of vertex stability leads to an improved treatment of T1 transitions in simulations and paves the way for studies of more biologically realistic models that couple topological transitions to the dynamics of regulatory proteins.

Honeycomb lattices with defects.

In this paper, we introduce a variant of the honeycomb lattice in which we create defects by randomly exchanging adjacent bonds, producing a random tiling with a distribution of polygon edges. We study the percolation properties on these lattices as a function of the number of exchanged bonds using an alternative computational method. We find the site and bond percolation thresholds are consistent with other three-coordinated lattices with the same standard deviation in the degree distribution of the dual; here we can produce a continuum of lattices with a range of standard deviations in the distribution. These lattices should be useful for modeling other properties of random systems as well as percolation.