IntroductionThe present study aimed to evaluate anxiety in patients and to monitor their heart rate (HR) and blood oxygenation (SpO2) before, during, and after a root canal treatment (RCT) during the state of alarm in 2 different periods of strict and partial confinement. MethodsThe patients who required a primary RCT were selected. Demographic, preoperative, and postoperative variables were registered, including perceived dental anxiety, fear, HR, and SpO2. Spearman correlation, chi-square, Mann-Whitney, and Kruskal-Wallis tests were used for frequency distribution and variable interaction, and Wilcoxon and Mann-Whitney tests were used to compare HR and SpO2 between groups and different treatment points. ResultsNinety-six patients were included. The median Modified Dental Anxiety Scale scores were 8 (interquartile range [IQR], 6–9.25) and 6 (IQR, 5.5–8) in patients treated during the strict and partial confinement periods. The median fear scores were 2 (IQR, 0–5) and 3 (IQR, 1–5), respectively. Having a previous dental bad experience resulted in higher dental anxiety and fear (P < .05). HR was increased in patients with higher MDAS and fear scores and in those treated during the strict confinement (P < .05). In treatment time points T6 (x-ray taking), and T7 (post-treatment), HR decreased compared with the other evaluated treatment time points (P < .05). No clinical differences were found regarding SpO2. ConclusionsSelf-perception on dental anxiety and fear was similar to other studies in a nonpandemic context. Patients with higher levels of dental anxiety and those treated in the strict confinement period presented an elevated HR. However, it can be stated that RCT performed by endodontists does not result in a significant alteration in patients.