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

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."

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.

A preregistered randomized controlled, split-mouth, single-blinded pilot feasibility trial (ClinicalTrials.gov ID 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.

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).

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.

Sura SK, Kowash M, Salami A, et al. Procedural Pain, Hall Technique Crowns and Separators: A Randomized Controlled Clinical Pilot Feasibility Study. Int J Clin Pediatr Dent 2026;19(3):357-367.