Dental erosion is the loss of dental hard tissues (enamel and dentine) by chemical dissolution in the absence of bacterial involvement. It has an increasing prevalence in Western populations leading to sensitivity and the need for complex dental rehabilitations. Development of preventative approaches and remineralisation interventions is limited by a lack of understanding on how variability in the hierarchical structure and composition of dental tissue influences erosion patterns.
We aim to probe the influence of hierarchical structure and the nanoscale distribution of calcium phosphate phases of dental hard tissues on erosion and remineralisation and study the change of mechanical properties of enamel and dentine subjected to erosion and remineralisation. Both lab based and synchrotron x-ray diffraction and x-ray absorption spectroscopy will be used to map the ultrastructural (hydroxyapatite crystallite texture) alignment of dental enamel and dentine. Transmission electron microscopy (TEM) characterisation of dental hard tissues in conjunction with electron energy loss spectroscopy (EELS) will be performed to determine crystallinity, nanostructure and phase composition with high spatial resolution. Synchrotron scanning transmission X-ray microscopy and XANES mapping will be used to determine the distribution of calcium phosphate phases at 50 nm resolution, enabling the observation of crystal-crystal differences. A specially designed Bruker Hysitron in-situ nanomechanical testing rig with Zeiss Xradia X-ray microscopy system be employed to allow visualisation of the interactions between the hierarchical structure of enamel, dentine and enamel dentine junction while indentation is taking place. The novel flow-cell model that the supervisory team is currently developing with national and international collaborators will be used to identify, monitor and quantify erosion and remineralisation processes of commercial oral health care products in a way not possible by other techniques.
The successful candidate will have access to the world-class characterisation facilities within the Henry Royce Institute at the University of Manchester, including X-ray imaging/tomography instruments at Henry Moseley X-ray Imaging Facility (HMXIF), suites of the latest electron microscopes and X-ray diffractometers, Solid State NMR and the state-of-the-art surface characterisation techniques such as nanoIR and Nano-Raman Spectroscopy. Candidate will also have the opportunity to conduct experiments at the UK National Synchrotron Facility, Diamond Light Source.
Applications are invited from UK/EU nationals only. Applicants must have obtained, or be about to obtain, at least an upper second class honours degree (or equivalent) in a relevant subject.
On the online application form select PhD Biomaterials Science and Dental Technology. For information on how to apply for this project, please visit the Faculty of Biology, Medicine and Health Doctoral Academy website(https://www.bmh.manchester.ac.uk/study/research/apply/)
EPSRC DTP studentship with funding for a duration of 3.5 years to commence in September 2019. The studentship covers UK/EU tuition fees and an annual minimum stipend (£15,009 per annum 2019/20). Due to funding restrictions the studentship is open to UK and EU nationals with 3 years residency in the UK.
As an equal opportunities institution we welcome applicants from all sections of the community regardless of gender, ethnicity, disability, sexual orientation and transgender status. All appointments are made on merit.
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