Methods: The experiments were carried out on 22 premolars which scheduled for extraction as part of orthodontic treatment. The study was approved by the University ethic committee. Dentin was exposed at the tip of the buccal cusp by cutting a cavity (diam. 3 mm, depth 3 mm) and etched with 35% phosphoric acid. The baseline pain sensation induced by probing and air blast was assessed on 10 cm Visual analogue scale (VAS). In group I, the cavity was filled with 10% articaine with 1:1,000 epinephrine. Then, the iontophoresis device (Dentaphore-II) was used with currents of 0.12 mA for 90 sec. Pain assessment to both stimuli was done again every 2 minute for 6 min and every 10 min for 30 min. Pulpal blood flow were also recorded with a laser Doppler flowmeter. In group II, the experiments were performed exactly the same as group I but the cavity was filled with distilled water.
Results: The means baseline VAS score caused by probing and air blast obtained from group 1 experiments were 5.14 ± 1.29 cm and 7.36 ± 1.27 cm, respectively. The corresponding value significant decreased to 0 (p<0.05, one- way RM ANOVA on rank,Dunett’s test) respectively immediately after iontophoresis. The subjects did not feel any pain to both stimuli Immediately after iontophoresis and last for 30 minutes. In group II, distilled water application had no significant effect on the mean VAS caused by both form of stimuli.
Conclusions: Iontophoretic delivery of 10% articaine with epinephrine through exposed dentin for produce pulpal anesthesia immediately and last for 30 minutes