Randomization and blinding
In this single-blind trial, a randomization sequence was generated in blocks of 30 to ensure that equal numbers of patients were allocated to each group. Thirty paper sheets (10 FMR, 10 HFT, and 10 CTR) were folded and placed in a basket (AW). Before treatment commenced, each patient selected a paper sheet from the basket for randomization. Until the moment of assignment, the allocation sequence was concealed from those assigning participants to the intervention groups. The orthodontists and the orthodontic assistants enrolled participants to their intervention group. The author assessing DL was not involved in the clinical data collection or in the treatment of the patients and was blinded to the patient’s group allocation. The patient’s group affiliation was revealed after the statistical analysis.