RESUMO
The aim of this study was to evaluate the effectiveness of F-File with NaOCl on removal of the smear layer. A total of 48 single-rooted teeth were instrumented using crown-down technique with one of the irrigation agents: distilled water, 5.25% NaOCl, RC-Prep, Glyde, MTAD or F-File with NaOCl. The remaining smear layer was scored at cervical, middle and apical thirds of the roots with SEM. In all the canals of experimental groups the coronal sections were cleaner than the middle and apical sections except with distilled water (P<0.001). In the coronal third, intensive smear layer was observed in distilled water, NaOCl and F-File groups and less smear layer in MTAD (P<0.05) and least in RC-Prep and Glyde groups. In the middle third, RC-Prep and Glyde groups had less smear layer than the other groups (P<0.001). In the apical third, there was intensive smear layer in all specimens and statistical analyses showed no significant difference among the groups (P>0.05). The F-file failed to improve the effect of NaOCl in removing smear layer.
Assuntos
Dentina/ultraestrutura , Preparo de Canal Radicular/instrumentação , Camada de Esfregaço , Ácido Cítrico/uso terapêutico , Cavidade Pulpar/ultraestrutura , Diamante/química , Doxiciclina/uso terapêutico , Ácido Edético/uso terapêutico , Desenho de Equipamento , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Peróxidos/uso terapêutico , Plásticos/química , Polissorbatos/uso terapêutico , Irrigantes do Canal Radicular/uso terapêutico , Hipoclorito de Sódio/uso terapêutico , Propriedades de Superfície , Ápice Dentário/ultraestrutura , Ureia/uso terapêutico , Água , Ceras/uso terapêuticoRESUMO
Most mandibular first molars have 2 mesial canals. Two cases of failed endodontically treated first mandibular molars are presented with 2 obturated mesial canals. The cases were retreated with a third mesial canal identified, and instrumented and obturated with resolution of the patients' signs and symptoms. These cases show that consideration must be made to recognize the possibility of a third mesial canal and perform complete treatment to minimize the possibility of failure.