RESUMEN
OBJECTIVE: The aim of this study was to evaluate the obturation of mesial root canals of mandibular first molars performed with different filling techniques and materials (gutta-percha and resilon). METHODS: Seventy-eight mesial root canals of human mandibular first molars were prepared using the K3 rotary system, and the apical preparation was set up to size 35.04. The root canals were obturated with single cone, System B, Thermafil and Real Seal 1 techniques using either gutta-percha/ThermaSeal Plus (n=13) or Resilon/Real Seal SE (n=13). Rhodamine B dye was incorporated into the sealers. Each specimen was horizontally sectioned at 2 milimeters (mm), 4 mm and 6 mm from the apex, and the samples were examined under a stereomicroscope to evaluate the presence and type of isthmuses and the percentage areas of gutta-percha/Resilon, sealer and voids. Confocal laser scanning microscopy (CLSM) was used to evaluate the sealer penetration into dentinal tubules. The Kruskal-Wallis and Dunn's tests were used to analyse the stereomicroscope data, while the ANOVA and Tukey tests were used to analyse the CLSM data (P<0.05). RESULTS: Thermafil and Real Seal 1 fillings showed more gutta-percha/Resilon and less sealer (P<0.05) at the 2 mm level, but the percentage of voids was similar in all groups (P>0.05). At the 4 mm level, more sealer (P<0.05) was found in the single cone groups using both materials. The System B groups exhibited better performance at the 6 mm level. The percentage of sealer penetration showed no statistically significant differences among the obturation techniques for all evaluated levels. Similar results (P>0.05) were found for both material/sealers. CONCLUSION: None of the materials or techniques completely filled the mesial root canals of mandibular molars, but the plasticised techniques were more efficient. The obturations using both materials and sealers were similar.
RESUMEN
INTRODUCTION: This study evaluated the physicochemical, antimicrobial, and biological properties of white mineral trioxide aggregate (MTA) mixed with aqueous and propylene glycol extracts of Arctium lappa L. and Casearia sylvestris Sw. METHODS: The setting-time test was performed according to American Society for Testing and Materials 266/2008 and flowability by American National Standards Institute/American Dental Association 57/2012 standard specifications. The following parameters were assessed: volumetric change by micro-computed tomography; pH level and calcium ion release measured after 3 hours and 1, 3, 7, and 15 days; antimicrobial effect by the dentin decontamination method with intratubular Enterococcus faecalis viability, verified by using confocal laser scanning microscopy; and biocompatibility by histologic-morphometric analyses of inflammatory infiltrate at subcutaneous implant sites after 15, 30, and 60 days. In addition, rat alveolar tissues with implants were processed to measure tumor necrosis factor-alpha and interleukin-10 cytokines by enzyme-linked immunosorbent assay. RESULTS: The plant extracts associated with MTA significantly increased the final setting time; however, they did not influence volumetric change (P > .05) and maintained medium alkalinity and calcium ion release. Propylene glycol extracts showed higher flowability. Casearia sylvestris increased the cementing effect against E. faecalis after 24-hour and 168-hour periods. Histologic evaluation of inflammatory infiltrate showed no significant differences between plant extracts groups and the distilled water group for all periods. Tumor necrosis factor-alpha and interleukin-10 expression was similar among groups (P > .05). CONCLUSIONS: Casearia sylvestris extracts increased the antimicrobial effect of MTA and did not influence biocompatibility but changed some physicochemical properties.