Attentional and physiological characteristics of patients with dental anxiety.

Twenty patients with dental anxiety were investigated while seated in a dental chair in a dental clinic. Heart rate (HR), heart rate variability (HRV), and skin conductance level (SCL) were recorded while the patients were exposed to scenes of dental treatment as well as a Stroop attentional task. Results showed an attentional bias with longer manual reaction times (RT's) to the incongruent compared to the congruent color words as well as the threat compared to the neutral words. Longer RT's to the incongruent and the threat words were found in the low HRV patients compared to the high HRV patients. Furthermore, all patients showed an increase in HR during exposure and the Stroop task compared to baseline. The HRV showed a decrease during the exposure and the Stroop task compared to baseline. HR and HRV did not differ between exposure and the Stroop task. Moreover, HR and HRV did not return to baseline levels during the recovery period. The SCL showed an increase from baseline to exposure, from exposure to the Stroop task and a decrease in the recovery phase. Results showed the importance of vagal cardiac control in attentional, emotional, and physiological processes in patients suffering from dental fear.