All patients will be treated using the fixed appliance on the upper and lower arches.

0.014" Niti archwire is used to ensure all patients will receive the same force.

All participants will receive a pain diary. In the pain diary, they are required to complete a KAP questionnaire regarding pain before the procedure. They are also required to record the pain VAS score at different times (before procedure, 6 hours, 12 hours, 24 hours, 3 days, 5 days and 7 days after procedure). For PCM 650mg group, 1 tablet will be given 1 hour before the procedure and every 6 hours for 24 hours (5 doses in total) (Nik et al., 2016) as pain begins two hours after activation, peak at 24 hours and reduces after two days (Nik et al 2016). Paracetamol if taken more than 4g per day may cause serious liver damage. United State of Food and Drugs Administration recently suggested a maximum daily dose of 3g to reduce risk of overdosing (Kim et al, 2020, FDA, 2011). Based on literature, 1000mg PCM is more efficient as postoperative analgesics 1000mg vs 650mg vs placebo (SPRID6 score of 529.4 vs 427.3 vs 60.0) (Qi et al, 2012). However, this study reported a single dose application (up to 6 hours). In view of continuous pain sensation experience by orthodontic patients (peak at 24 hours), we concluded that 650mg 6 hourly is more appropriate to control pain experienced by participants. For LLLT group: ezlase diode laser beam (Biolase, USA) for soft tissue operated at 940nm wavelength will be applied using a quadrant-sized probe that covers region form central incisor to first molar at the level of cervical third of the root, perpendicular and in light, direct contact with the buccal and palatal mucosa for the upper arch and buccal and lingual mucosa for the lower arch from UR6-UL6 and LR6- LL6 for 30 seconds each site (AlSayed Hasan et al., 2018; Qamruddin et al., 2021). Patients will be monitored up to 1 hour after the LLLT application for any adverse reactions. All procedures will be conducted in the morning session from 9am- 11am. Due to variability of pain experienced throughout the day (Aviram et al, 2015), patients are advised to record pain in the morning to reduce the variability in VAS score. All the procedures and baseline score will also be conducted and recorded in the morning.

During the follow-up appointment (1 month after bond-up) Patients are required to re-answer the KAP questionnaire (post bond-up) in the pain diary. Pain diary will be collected for data analysis.