Tetracycline HCl solution as a root canal irrigant

The effect of tetracycline hydrochloride as an endodontic irrigant on smear layer removal was examined by scanning electron microscopy and compared wi th bidistilled water, 2.5% sodium hypochlorite (NaOCl), and 50% citric acid in 20 extracted teeth. Five teeth, as a control, were irrigated with bidis tilled water only in group 1. All the other groups were irrigated with NaOC l during instrumentation. The final rinses were NaOCl in group 2, citric ac id in group 3, and 1 % tetracycline hydrochloride in group 4. Scanning elec tron microscopic results and statistical analysis revealed that bidistilled water and NaOCl were ineffective in removing the smear layer, whereas citr ic acid and tetracycline hydrochloride were significantly more effective (p < 0.001). No statistically significant difference was detected between tet racycline hydrochloride and citric acid (p > 0.05). However tetracycline hy drochloride demineralized less peritubular dentin.