Analysis of Pain and Effectiveness in Digital Block of the First Toe Using Syringe vs. Carpule: Frost's H vs. Modified Frost's H Randomized Clinical Trial.

Background : Currently, there is no scientific evidence regarding pain in the anesthetic block of the first toe according to the method of application. However, clinical evidence has highlighted the use of the carpule due to the low pain it causes during the administration of the anesthetic. Most studies on anesthesia and pain, especially using the carpule and distraction methods, belong to the field of dentistry. Objective : To compare the pain and effectiveness between the anesthetic block of the first toe using a carpule and syringe with Frost's H technique and the modified Frost's H technique. Method : A total of 564 subjects were selected and divided into four groups. Subjects were subjected to experimental conditions (randomization through the Random Allocation Software program 2.0), and divided into group 1 = 138 subjects, corresponding to the block with syringe and Frost's H, group 2 = 141 subjects, corresponding to the syringe group and modified Frost's H, group 3 = 141 subjects, corresponding to the carpule group and modified Frost's H, and group 4 = 144 subjects, corresponding to the carpule group and Frost's H. The same researcher generated the random allocation sequence, enrolled the participants, and assigned them to the interventions. Each subject was unaware of the anesthetic procedure assigned by the researcher. Outcome parameters were pain after anesthetic infiltration and its effectiveness. Results : The anesthetic block with carpule showed a lower pain score compared to the anesthetic block with syringe (2.8 vs. 5.3; p < 0.001). However, when analyzing effectiveness, a higher efficacy rate was obtained in the anesthetic blocks performed using the modified Frost's H technique (97.5% vs. 88.1%; p < 0.001). Conclusions: The anesthetic block with carpule and the modified Frost's H technique is less painful and more effective than the traditional anesthetic block.