RESUMO
Background: The effectiveness of endodontic retreatment essentially depends on the cleaning and/or disinfection processes. In this context, the removal of root canal filling materials plays a crucial role. Aims: To assess the efficacy of passive ultrasonic irrigation (PUI), EndoActivator system (EAS), and XP-endo Finisher R (XPEFR) as additional cleaning techniques to remove the remaining root canal filling materials from flattened root canals. Subjects and Methods: Thirty-six similar flattened distal root canals of extracted human first lower molars were selected by micro-computed tomography (micro-CT) and then instrumented and filled. After the initial retreatment procedures, the residual volume of root canal filling materials was assessed by micro-CT (V1). Then, the specimens were divided into three groups (n. 12), according to the additional cleaning technique and submitted to another micro-CT scan (V2). Statistical Analysis Used: Analysis of variance and Games-Howell tests (P < 0.05). Results: The percentage reduction in the residual volume of root canal filling materials reached by PUI, EAS, and XPEFR was 28.38%, 28.12%, and 43.52%, respectively, considering the total space of the root canal (P > 0.05). In the apical third, these values were 20.05%, 21.54%, and 48.82% (P < 0.05). Conclusions: Additional cleaning techniques enabled removing a greater amount of root canal filling material from flattened distal root canals of extracted human first lower molars. Considering the total space of the root canal, there were no statistically relevant differences among the groups. In the apical third, XPEFR performed better.
RESUMO
This study evaluated the impact of different concentrations of glyphosate (Rondup(®)) on planktonic and biofilm growth of P. aeruginosa. Aerobic and anaerobic cultures of P. aeruginosa ATCC(®)15442 inoculated in MHB + glyphosate (0.845 ppm, 1.690 ppm, 8.45 ppm, 16.90 ppm, 84.50 ppm, 169 ppm, 845 ppm, and 1690 ppm) and cultured in normoxia and anoxia, following their OD(560nm) every hour for 24 h. Biofilms of adapted cells were formed in the presence of glyphosate (0.845 to 1690 ppm) in normoxia and anoxia for 36 h. Glyphosate at concentrations higher than 84.5 ppm reduces the cell density of planktonic aerobic cultures (p < 0.05). However, these same concentrations favor the planktonic anaerobic growth (p < 0.05). On the other hand, the herbicide favors a slight growth of biofilms in a concentration-dependent manner up to 84.5 ppm (p > 0.05), and more pronounced over 169 ppm. Anaerobic biofilms have their growth more readily favored (p < 0.05), regardless of concentration. In a concentration-dependent manner, glyphosate interferes with the growth ability of P. aeruginosa ATCC(®)15442.
Assuntos
Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Glicina/análogos & derivados , Herbicidas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Aerobiose , Anaerobiose , Biomassa , Glicina/metabolismo , Espectrofotometria , GlifosatoRESUMO
This study evaluated the impact of different concentrations of glyphosate (Rondup®) on planktonic and biofilm growth of P. aeruginosa. Aerobic and anaerobic cultures of P. aeruginosa ATCC®15442 inoculated in MHB + glyphosate (0.845 ppm, 1.690 ppm, 8.45 ppm, 16.90 ppm, 84.50 ppm, 169 ppm, 845 ppm, and 1690 ppm) and cultured in normoxia and anoxia, following their OD560nm every hour for 24 h. Biofilms of adapted cells were formed in the presence of glyphosate (0.845 to 1690 ppm) in normoxia and anoxia for 36 h. Glyphosate at concentrations higher than 84.5 ppm reduces the cell density of planktonic aerobic cultures (p < 0.05). However, these same concentrations favor the planktonic anaerobic growth (p < 0.05). On the other hand, the herbicide favors a slight growth of biofilms in a concentration-dependent manner up to 84.5 ppm (p > 0.05), and more pronounced over 169 ppm. Anaerobic biofilms have their growth more readily favored (p < 0.05), regardless of concentration. In a concentration-dependent manner, glyphosate interferes with the growth ability of P. aeruginosa ATCC®15442.
Assuntos
Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Glicina/análogos & derivados , Herbicidas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Aerobiose , Anaerobiose , Biomassa , Glicina/metabolismo , EspectrofotometriaRESUMO
This study evaluated the impact of different concentrations of glyphosate (Rondup®) on planktonic and biofilm growth of P. aeruginosa. Aerobic and anaerobic cultures of P. aeruginosa ATCC®15442 inoculated in MHB + glyphosate (0.845 ppm, 1.690 ppm, 8.45 ppm, 16.90 ppm, 84.50 ppm, 169 ppm, 845 ppm, and 1690 ppm) and cultured in normoxia and anoxia, following their OD560nm every hour for 24 h. Biofilms of adapted cells were formed in the presence of glyphosate (0.845 to 1690 ppm) in normoxia and anoxia for 36 h. Glyphosate at concentrations higher than 84.5 ppm reduces the cell density of planktonic aerobic cultures (p < 0.05). However, these same concentrations favor the planktonic anaerobic growth (p < 0.05). On the other hand, the herbicide favors a slight growth of biofilms in a concentration-dependent manner up to 84.5 ppm (p > 0.05), and more pronounced over 169 ppm. Anaerobic biofilms have their growth more readily favored (p < 0.05), regardless of concentration. In a concentration-dependent manner, glyphosate interferes with the growth ability of P. aeruginosa ATCC®15442.