This study aimed to evaluate cardiac activity changes during lower third molar surgery concerning gender and anxiety levels. Thirty healthy subjects who required lower third molar surgery filled out Norman Corah dental anxiety scale (DAS) before surgery. A patch ECG device (Savvy, Institute ''Jožef Stefan'', Ljubljana, Slovenia) was applied to the patient to evaluate heart rate (HR) and heart rhythm. These parameters were assessed in 8 different intervals. Periods of the highest mean HR values—incision and flap elevation compared to the period with minimal mean HR values—during suturing showed statistical significance difference (p<0.05). The most common outstanding ECG finding was sinus tachycardia, especially in anxious compared to non-anxious patients. Extraction difficulty score was correlated with the procedure duration time and with the abnormal ECG findings in the period of tooth extraction. Significant cardiac activity changes are detected during surgery. Physiological manifestations of anxiety may be evaluated successfully using a patch ECG device.