Electrodermal activity, dental anxiety, and fear of dentistry in a group of parenteral drug addicts.

The present study was undertaken in order to evaluate whether electrodermal activity was a useful tool with which to measure dental anxiety in a group of drug addicts. Electrodermal activity was compared to the subjects' self-reported feelings during ordinary dental treatment sessions. In the first part of the study the level of electrodermal activity during treatment sessions was videotaped and recorded on paper by means of a polygraph. The patients were interviewed using a semi-structured questionnaire dealing with the addicts' dental anxiety and fear. In connection with the interviews the addicts completed Corah's Dental Anxiety Scale (CDAS). There was no recognizable pattern in electrodermal activity when this was compared with the patients' feelings during the treatments. Median CDAS was 9.5. In the second part of the study, electrodermal activity was recorded on the polygraph only. This group also completed a CDAS questionnaire. No correlation between the patients' self-reported highest level of anxiety and level of electrodermal activity, number of fluctuations or amplitude in relation to specific dental stimuli was found; agreement was found in two, three and none of 10 cases respectively. Median CDAS was 10.0. It could be concluded that, although the study revealed apprehension and situational anxiety among the addicts, no correlation to electrodermal activity was found. This discrepancy between the physiological and cognitive data probably reflects the uncertainty of these measures under the given circumstances.