Effectiveness of supplementary irrigant agitation with the Finisher GF Brush on the debridement of oval root canals instrumented with the Gentlefile or nickel titanium rotary instruments

AIM: To examine the efficacy of a novel supplementary irrigant agitating brush (Finisher GF Brush, MedicNRG, Kibbutz Afikim, Israel) on the debridement of root canals prepared with a novel stainless steel rotary instrumentation system (Gentlefile; MedicNRG), or nickel titanium rotary instruments in oval root canals. METHODOLOGY: Mandibular premolars (n = 72) were selected and divided randomly into three experimental groups (n = 24) after microCT scanning: group 1, canal preparation to rotary NiTi size 20, .04 taper (R20); group 2, rotary NiTi to size 25, .04 taper (R25) and group 3, Gentlefile size 23, .04 taper (GF). Specimens were subdivided into two subgroups: subgroup A, syringe-and-needle irrigation (SNI); subgroup B, Finisher GF Brush (GB). Ten untreated canals served as controls. Specimens were processed for histological evaluation, and the remaining pulp tissue (RPT) was measured. Data were analysed using Mann-Whitney and Kruskal-Wallis tests (P = 0.05). RESULTS: All experimental groups had significantly less RPT than the control (P   0.05). When instrumented with R20, there was no significant difference between SNI and GF (P < 0.05) whilst GB had significantly less RPT than SNI for R25 (P < 0.05). CONCLUSIONS: Supplementary irrigant agitation with the Finisher GF Brush improved the debridement of canals prepared with Gentlefile and size 25, .04 taper rotary NiTi. Root canal debridement did not significantly differ between the instruments when syringe irrigation was used.