Comparing antimicrobial effect of cupral and calcium hydrox-ide paste with electrophoresis in apical part of root canals blocked by separated instrument

This study compared the antimicrobial effect of electrophoresis with calcium hydroxide and electrophoresis with cupral paste in the apical area blocked by the separated instrument.

A total of 72 single-rooted human teeth were involved in the study, each decoronated to a length of 15 mm. Following the determination of the working length and root canal preparation, the teeth were autoclaved and subsequently infected with Enterococcus faecalis. Intentional fracture of a rotary instrument occurred 3mm above the apical terminus of the canal. The samples were then randomly assigned to six groups: Groups G1 and G2 received Cupral paste (Hu-manchemie GmbH, Germany) and calcium hydroxide paste (Humanchemie GmbH, Germany), respectively, with the application of electric current. In G3, sterile normal saline was used with electrophoresis. For G4 and G5, Cu-pral and calcium hydroxide pastes were applied to the root canal without electrical current, respectively. G6 was used as the positive control. Following all in-terventions, the 3mm apical segment of the specimens was removed, and the antimicrobial effect was assessed by counting colony-forming units (CFUs) in this ca-nal area.

Cupral paste, Cupral paste with electrophoresis, and calcium hydroxide with electrophoresis demonstrated a significant reduction in bacteria beyond the separated instrument (p<0.05). However, calcium hydroxide and electrophoresis alone did not exhibit statistically significant antimicrobial activity (p> 0.05). There was no statisti-cal difference observed between Cupral paste activated by electrophoresis and calcium hydroxide activated by electrophoresis (p> 0.05).

Electrophoresis enhanced medicament penetration and antimicrobial ef-ficiency in the canal blocked by the separated instrument. Cupral paste activated by electrophoresis demonstrated superior performance in all interventions.