Randomizing process and blinding
The randomization process was previously conducted by an independent researcher who was blinded to the patients and interventions. Each intervention was written, drawn, and sealed in opaque envelopes before starting the study. The interventions were drawn as “A” for the test group, which received jaw exercises and counselling, and “B” for the control group, which received only counselling program. Only the researcher responsible for the interventions knew the envelope content. The numbers corresponding to the patients and the interventions (classified as “A” and “B”) were placed in opaque envelopes. Thus, each patient had their corresponding numbers placed on the envelopes along with the intervention, assigned by lottery. Each patient received the allocated intervention, which was taken from the envelope at the appointment time, and the clinician only knew the intervention to be applied at the time to execute it. The allocation remained hidden until the time of the intervention. The interventions were always executed by the same researcher, who did not participate in the evaluations.