There was a statistically significant difference in TNF-α concentration at 24 h after orthodontic force application in the PEA group as compared to baseline (P < 0.05). Meanwhile, significant differences were observed at 24 h and 168 h after orthodontic force application in the SL system as compared to baseline (P < 0.05). The mean TNF-α value was significantly elevated at 24 h after force application in the PEA and SL groups.
preadjusted edgewise appliance (PEA)
without orthodontic treatment
TNF-α levels after 168 h