Effects of cognitive therapy, applied relaxation and nitrous oxide sedation. A five-year follow-up study of patients treated for dental fear

Five years after completing a controlled, randomized treatment trial comparing the effect of nitrous oxide sedation (NO), cognitive therapy (CT), and applied relaxation (AR), all 62 patients who had participated were invited to a follow-up questionnaire study. Forty-three responded. All participants had been to the dentist during the follow-up period. Mean scores (s) on Corah's Dental Anxiety Scale (CDAS) and Symptom Checklist 90 Revised (SCL-90-R, a measure of general psychological distress) were 10.4 (4.1) and 0.35 (0.34), respectively. There were no between-group effects. Significant changes across the assessment phases (at enrollment, after treatment, and 5 years after) were found for both dental fear and general distress (CDAS: F = 137.8, P < 0.01; SCL-90-R: F = 12.5, P < 0.01). However, no significant changes between measures obtained after treatment and at follow-up emerged. Seven participants (3 from the NO group, 2 from the CT group, and 2 from the AR group) had CDAS scores above 14, indicating a recurrent or continual dental fear problem. The majority (81%) assessed the dental fear treatment received 5 years previously to have been useful for them. In conclusion, the favorable effects on dental fear and general psychological distress continued at 5-year follow-up for all treatment groups.