Objective: To evaluate the effectiveness of professionally applied fluoride varnish on the incidence of dental caries amongst older adults resident in LTCFs in Northern Ireland. Background:The oral health status of older adults within Long-Term Care Facilities (LTCFs) is significantly worse than their community living peers. Whilst evidence suggests an important role for fluoride varnish in preventing caries in this population, very few studies have evaluated this intervention. Materials and Methods: A quality improvement project was undertaken with dentate residents (n = 190) in nine LTCFs who had fluoride varnish applied by Dental Care Professionals on two separate occasions during a 12-month period (intervention group). Nine LTCFs were chosen as matched controls (control group) with comparable numbers of residents of similar medical status (n = 217). For the intervention group, oral hygiene training was also provided for the care home staff. Results: A total of 407 patients (n = 271 female) were included in the analyses (mean age [SD]: 84.1 [6.6] years). After 12 months, the intervention group recorded a significant reduction in mean number of carious teeth (mean [95% CI]: −0.85 [−1.12, −0.58]; P < .001). Patients in the control group had significant increases in the mean number of carious teeth (mean [95%

The presence of a stenosis caused by the abnormal narrowing of the lumen in the artery tree can cause significant variations in flow parameters of blood. The original flow, which is believed to be laminar in most situations, may turn out to turbulent by the geometric perturbation created by the stenosis. Flow may evolve to fully turbulent or it may relaminarise back according to the intensity of the perturbation. This article reports the numerical simulation of flow through an eccentrically located asymmetric stenosis having elliptical cross section using computational fluid dynamics. Large eddy simulation technique using dynamic Smagorinsky sub-grid scale model is applied to capture the turbulent features of flow. Analysis is carried out for two situations: steady inflow as ideal condition and pulsatile inflow corresponding to the actual physiological condition in common carotid artery. The spatially varying pulsatile inflow waveforms are mathematically derived from instantaneous mass flow measurements available in the literature. Carreau viscosity model is used to estimate the effect of non-Newtonian nature of blood. The present simulations for steady and pulsatile conditions show that post-stenotic flow field undergoes transition to turbulence in all cases. The characteristics of mean and turbulent flow fields have been presented and discussed in detail.

A simple, robust, local divergence free, second-order accurate, stable solution procedure for incompressible flows using a finite element method for the evaluation of velocity components and a finite volume method for the evaluation of pressure is presented. In order to ensure pressure stability, the velocity components (at vertices) and pressure (at cell centres) are evaluated at different points of the elements. The finite element-finite volume combinations are taken from triangular and quadrilateral grids. These grids are used alone or together as mixed grids. A new element-cell configuration consisting of two adjacent triangular elements together as a finite volume quadrilateral cell for the evaluation of pressure is introduced. Predictions are found to be in good agreement with the available results for all types of grids used. The present method combines the pressure stability of the staggered grid finite volume method (FVM) and the flexibility of the finite element approach to analyse flow through complex geometries; it is easy to implement and locally divergence free.

Atherosclerosis caused by the deposition of plaques inside artery walls is a major cause of death in the world. It is well known that, fluid dynamics of blood through arteries play a vital role in the development of atherosclerosis. Experimental investigations of vascular flow and dynamics are very complicated due to the small dimensions involved, intricacy of vessel structure and the requirement of complex boundary conditions. Therefore, development of theoreticalmathematical models and computer simulations using the tools of Computational Fluid Dynamics (CFD) are very important. Flow of blood inside arteries can be described by fundamental equations of fluid dynamics. Numerical methods can be used to solve these equations for simulating blood flow through arteries and to investigate the flow physics under different conditions. In this work, flow structures inside a stenosed artery model is analysed using Large eddy simulation(LES) technique under steady and pulsatile conditions. The variation of wall shear stress and the distributions of velocity and vorticity in accordance with the stenosis severity levels are presented.

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