Participant flow
RECRUITMENT
A flow chart of participants through the trial is shown in CONSORT participant flow chart.Adapted from A single patient in the intervention group withdrew from the study after the 32-week indices, as he wished to start using an electric toothbrush.Recruitment for the trial began on 15 November 2019. The first patient to be recruited started the trial on 6 January 2020. The trial was stopped early after the interim analysis of results on 2 November 2021. At the point of stopping the trial, 85% of data had been collected. A total of 40 participants had been recruited; all 40 participants had indices at 8 weeks (n = 20 intervention, n = 20 control); 32 participants had indices at 32 weeks (n = 17 intervention, n = 15 control); and 19 participants had indices at 56 weeks (n = 9 intervention, n = 10 control).Fewer dropouts occurred than expected. At the interim analysis of results, the power calculation had been met for both groups at 56 weeks. Due to the constraints caused by the COVID-19 pandemic and extra pressure on the NHS, it was unethical to continue with the trial.