Comparative study of two different computer-controlled local anesthesia injection systems in children: a randomized clinical trial.

PURPOSE: To compare pain perception associated with two computer-controlled local anesthesia devices, the WAND STA (Milestone Scientific Inc., Livingston, NJ, USA) and the Calaject (Ronvig dental MFG, Daugaard, Denmark) in young children. METHODS: A split-mouth randomized clinical trial comprising 30 patients, aged 6-12 years, received randomly, in two separate sessions, a local anesthesia injection in the maxillary using either the wand STA or the Calaject. Pain perception was evaluated using the patient's heart rate, an 11-point numerical scale (NRS), and the Sound, Eye, and Motor (SEM) body movements. Statistical difference was set at p = 0.05. Repeated measures analysis of variance were conducted to compare the mean pulse for Calaject and STA at different times. It was followed by univariate analysis and Bonferroni multiple comparisons tests. Wilcoxon tests were performed to compare NRS, SEM, and injection duration between Calaject and STA. RESULTS: There was no significant statistical difference between Calaject and STA in pulse rate before injection (p = 0.720), during injection (p = 0.767), and after injection (p = 0.757). The mean NRS score was significantly greater with STA in comparison with Calaject (p = 0.017). The mean SEM score was also significantly greater with STA in comparison with Calaject (p = 0.002). However, the mean duration was significantly longer with Calaject (p = 0.001). CONCLUSIONS: Calaject was more effective than STA in reducing pain perception associated with periapical injection in young children.