Photodynamic antibacterial evaluation of polydopamine nanoparticle optimised Curcumin Longa against endodontic biofilm—An in‐vitro study

Abstract This study aims to evaluate the effect of antimicrobial photodynamic therapy(aPDT) with polydopamine nanoparticle functionalised with Curcuma longa (nPD‐Cur) against root canal biofilm. nPD‐Cur was prepared and characterised using Scanning Electron Microscopy(SEM), dynamic light scattering(DLS), Fourier‐transform infrared spectroscopy(FTIR) and Ultraviolet visual(UV/Vis) spectrophotometry. Root sections (10 mm length) were obtained from 53 single‐rooted human premolars and chemo‐mechanically prepared followed by inoculation with E. faecalis . All the specimens were randomly divided into five groups( n = 10) and irrigated (Group 1—Saline; Group 2—2.5% Sodium hypochlorite(NaOCl); Group 3—Cur; Group 4—nPD; and Group 5—nPD‐Cur) followed by diode irradiation and analysed for reduction in colony‐forming units(CFU)/mL, bacterial viability using Confocal Laser Scanning Microscopy(CLSM) and SEM for biofilm disruption. Results were analysed using one‐way ANOVA followed by post hoc Tukey's test for pairwise comparison ( p < 0.05). nPD‐Cur revealed the characteristic absorption patterns. The antimicrobial potency was highest for NaOCl followed by nPD > Cur‐nPD > Cur.