The use of dental implants has become a common treatment for the replacement of missing or damaged teeth. It is estimated that 10% of the world’s population will need a dental implant in their lifetime. However, still up to 11% dental implants will fail due to simultaneously occurring biomechanical and biological issues such as stress shielding, inappropriate osseointegration and bacterial infections known as peri-implantitis. To increase the clinical success of dental implants, cell-instructive surfaces that enhance the osseointegration process with the host tissues and at the same time prevent or suppress bacterial colonisation are needed. Current approaches are mainly relied on topographic and/or physicochemical modification of the implant surfaces to confer them the ability to induce a biological response and accelerate the bone/soft tissue regeneration process. Commercial dental implants normally use sandblasting and acid-etching to produce micro/nano-roughened surfaces to enhance the osseointegration, but most of them do not possess antimicrobial properties. Nature has shown that some specific micro/nanopatterns are able to control the bacterial adhesion (like on shark skin) and viability (like on cicada and dragonfly wings). Inspired by Nature, these micro/nano-patterned surfaces could be adapted on dental implants to facilitate the osseointegration process while preventing the bacterial colonisation.

The aim of this project is to investigate cell-instructive surfaces with combined micro/nano-patterns on dental implant materials, i.e. titanium and a newly developed biomimetic zirconia/polymer composite to promote osseointegration while preventing bacterial infections. Laser micromachining, plasma and/or alkaline etching will be used to generate well-defined micro/nanopatterns on titanium and zirconia/polymer composite substrates. Oral bacterial and stem cells responses will be investigated to the designed surfaces with microgrooves with/without superimposed nanowires or nanonetworks.

1. Generation and characterisation of micro/nano-patterned surfaces.

Microgrooves with or without superimposed nanopatterns (nanowires and nanonetworks) will be generated on titanium and zirconia/polymer composite substrates using laser micromachining and plasma or alkaline etching. The micro/nanopatterned surfaces will be fully characterised using a range of analytical and microscopy techniques including contact angle measurement, chemical composition (XPS, EDX) and feature size and shape (SEM, TEM).

2. Stem cells response to micro/nanopatterned surfaces

Biocompatibility and osteogenic potential of mesenchymal stem cells (MSCs) will be evaluated in vitro. MSC adhesion, growth and viability will be tested at different time points of culture. Immunofluorescence microscopy and SEM will be used to image vinculin in adhesions and cell morphology/interaction with the micro/nanopatterns. Osteogenic differentiation will be evaluated using qPCR to survey transcripts linked to growth and osteogenesis.

3. Oral bacterial response to micro/nanopatterned surfaces

Bacterial viability of the micro/nanopatterned surfaces will be assessed by measurement of bacterial metabolic activity and viability using BacTiter-Glo Viability and Live/Dead assays. SEM will be used to image bacteria-surface interactions. Peri-implantitis associated oral pathogens such as Fusobacterium spp. and Streptococcus spp. will be tested. Functionalisation of micro/nanopatterned surfaces will be investigated to further enhance the antimicrobial properties.

University of Bristol Scholarship - How to apply

You can submit an application via the University of Bristol application portal: Start your application | Study at Bristol | University of Bristol selecting the relevant 4-year PhD programme, e.g. “Oral and Dental Sciences (PhD) (4yr)”.

Search for your programme and select ‘apply’. Please choose the September 2025 start date.

Link to prospectus pages for Translational Health Sciences giving entry requirements and admissions statement: Oral and Dental Sciences | Study at Bristol | University of Bristol

In the funding section of the application form, please indicate “University of Bristol Scholarship”.

In the research section please enter the project title of the scholarship you are applying for along with the supervisor's name. You can upload a blank document instead of the research statement, which is not needed.

We are keen to support applicants from minority and under-represented backgrounds (based on protected characteristics ) and those who have experienced other challenges or disadvantages. We encourage you to use your personal statement to ensure we can take these factors into account.

We will also be running a pre-application online workshop and Q&A session on how to prepare a PhD application on 5 ^th December 2024 04:00 PM GMT; if you would like to register for this workshop then please sign up here.

The application deadline is 4pm on Monday 6th January 2025. The anticipated start date for this project is September 2025.

Application enquiries

Professor Bo Su

[email protected]