Fig. 2

Schematic representation of the main stages of the experimental protocol adopted in the study. The timeline illustrates the sequence of procedures performed: initial measurement of vital signs; administration of evaluation questionnaires; baseline saliva collection; 30-min interval before medication administration; medication administration; beginning of the surgical procedure; intraoperative measurements (heart rate, blood pressure, and pulse oximetry) taken at the following time points: preoperative, beginning of surgery, anesthesia, incision, extraction, suturing, and postoperative; immediate postoperative saliva collection; new measurement of vital signs; and re-administration of questionnaires 30 min after the end of surgery. All procedures were conducted according to a previously standardized protocol, ensuring consistency and comparability among participants.