This is a double-blinded randomised controlled trial that aims to measure the salivary fluoride concentration following tooth-brushing with several toothpaste formulations. Power calculations were performed using PASS 11.0 software, and calculations showed that 3 participants are needed in each group in order for results to be considered as significant. We will aim to recruit five to seven participants in each of the 12 groups. Research will be publicised by means of flyers and circulating emails amongst University of Leeds students. Information sheets will be provided to all participants and informed consent will be obtained.