Abstract
This study investigated the use of salivary and serum chromogranin A (CgA) as biomarkers of acute stress and pain perception during the initial phase of fixed orthodontic treatment. Twenty-five patients aged 15-25 years, scheduled for non-extraction therapy with fixed appliances, were enrolled, and unstimulated saliva as well as venous blood samples were collected at baseline, 24 h, 72 h, and one month after appliance placement. Pain levels were measured using a 10-cm visual analogue scale (VAS). Both salivary and serum CgA levels showed a significant rise at 24 h compared to baseline, followed by a gradual return towards baseline by one month. Pain intensity peaked at 24 h (mean 8.07 ± 1.18) and decreased at 72 h and one month, with female participants reporting higher pain scores than males at 24 h. No significant gender differences were observed in CgA levels. The similar patterns of biomarker increase and self-reported pain indicate that CgA reflects the short-term stress response linked to appliance placement. Monitoring salivary CgA could thus offer clinicians a non-invasive method to predict discomfort, facilitate early interventions, and help patients adapt to orthodontic treatment.