REMOVAL OF INTRACANAL SMEAR BY DOXYCYCLINE IN-VITRO

Cleansing and shaping result in a smear layer on the instrumented cana l wall surfaces. The smear layer may inhibit close contact between sea lers and. dentin, and inhibits diffusion of medicaments. Objective. Th is study assessed the effect of doxycycline hydrochloride (DH) on smea r layer on intracanal walls. Study design. Scanning electron microscop y was used to evaluate the remaining smear layer using different conce ntrations of DH. Single-canal palatal roots of extracted maxillary mol ars were irrigated with saline - 15% EDTA; saline - 25 mg/ml DH; salin e - 50 mg/ml DH; saline - 100 mg/ml DH; NaOCl - 15% EDTA; NaOCl - 25 m g/ml DH; NaOCl - 50 mg/ml DH; and NaOCl - 100 mg/ml DH. The roots were fractured into halves and the amount of smear layer assessed in the m iddle and apical third. Results. Doxycycline-HCl of 100 mg/ml was the most effective in removing smear layer. In the saline group, 100 mg/ml of DH was more effective than EDTA. In the hypochlorite group, 50 mg/ ml and 100 mg/ml of Dl-l were more effective than EDTA (p < 0.05). Con clusion. Doxycycline solution may be an effective irrigant.