Dental treatments of high dental anxiety patients (n = 20) under hypnotic conditions were investigated. Time need of main hypnotic events like rapport; induction: deepening; calming: developing imagination; dehypnosis; discussion was measured. Total time was significantly higher (p < or = 0.05) than pure dental treatment time, but the time the patients percepted was significantly less then total (p < or = 0.05), even somewhat less then pure dental treatment time. Time distortion correlated significantly (negative Pearson's correlation; p < or = 0.05) with the time need of rapport (-0.50), calming (-0.51) and dehipnosis (-0.46), and with the time need of developing delightful imagination (+0.57) (positive Pearson's correlation; p < or = 0.05). There was no significant correlation between time distortion and the time need of hypnotic induction, deepening, total time need of hypnosis, or pure dental treatment time.