Randomization, allocation concealment, and blinding
Participants who fulfilled the above selection criteria were identified and invited to take part in this study. Written informed consent and assent were obtained from the parent/guardian and participant, respectively. They were subsequently randomized (46 in each group) into either the intervention test (powered toothbrush) or control (manual toothbrush) groups (CONSORT flow diagram showing participant flow through the trial.An electronic randomization programme was used, whereby an equal allocation sequence was generated for the 92 participants meeting the initial acceptance criteria. The numbers were randomly assigned to either one of the two groups and placed in pre-prepared opaque envelopes, ensuring they were all identical and tamper evident. In the presence of a research nurse, a single envelope was then selected randomly by the participants and opened immediately following the placement of their appliances.The clinician assessing the outcomes was blinded to the randomization allocation, with a research nurse working independently to provide the oral hygiene instruction and to address any toothbrush or toothpaste replacement issues. Further blinding was undertaken during statistical analysis, aimed to further minimize bias.