Procedural Pain, Hall Technique Crowns and Separators: A Randomized Controlled Clinical Pilot Feasibility Study

Background:The Hall technique (HT) uses elastomeric orthodontic separators (EOSs) and stainless steel crowns (SSCs).Recent research highlighted that HT was reported to cause "procedural pain." Aim: To assess bilateral HT EOSs and SSCs "procedural pain, " and to evaluate the immediate effect of benzocaine 20% topical anesthesia gel (BZG) on child-perceived pain levels post-EOSs placement.Materials and methods: A preregistered randomized controlled, split-mouth, single-blinded pilot feasibility trial (ClinicalTrials.govID NCT06272903) was conducted in children (N = 32) requiring bilateral HT-SSCs after BZG/placebo (both strawberry flavored) were flossed interdentally prebilateral EOSs placement.Immediate child/parent proxy pain scores post-EOSs placement (n = 104) and SSC (n = 64) cementation were recorded [using the Wong-Baker faces pain rating scale (WBFS)].Statistical analysis-Wilcoxon signed-rank test.Significance level set at p < 0.05.Results: Bilateral SSCs placement resulted in low child-perceived pain compared to bilateral EOSs placement (p = 0.001).BZG significantly reduced immediate child pain perception when four EOSs (two mesial and two distal) were placed per child (p = 0.045), but this was not significant when two EOSs per child were placed.Separator load/number was related to pain; pain perception was significantly higher when two placebo EOSs were placed per tooth compared to one placebo EOS per tooth (p = 0.045). Conclusion:In children receiving bilateral HT-SSCs, procedural pain was related to EOSs placement rather than HT-SSC cementation.When using four EOSs in children receiving bilateral HT-SSCs, BZG reduced immediate pain perception.This pilot feasibility study paves the way for a larger trial.