RESUMEN
OBJECTIVE: To compare the efficacy of manual and mechanical instrumentation techniques, including ProTaper Universal retreatment system, Mtwo retreatment system, Reciproc system, and Hedström files, regarding removal of overextended root canal filling material. MATERIALS AND METHODS: Eighty extracted human mandibular premolar teeth were prepared at the apical foramen level using Revo-S rotary files and subsequently obturated. The root canal filling material was deliberately extruded from the apex. Samples were transferred to glass vials that simulated the periapical area. Eighty samples of overfilled teeth were randomly assigned to four equal groups (n = 20) for removal of the root filling material with ProTaper Universal retreatment files (Group 1), Mtwo retreatment files (Group 2), Reciproc system (Group 3), and hand files (Group 4). Removal of the root canal filling material and additional preparation were performed by individual instruments from each different system up to a #40 size. The external apical surface of the teeth and the surrounding glass vials were checked using a dental operation microscope with ×12.5 magnification. Samples were divided into two groups based on whether removal of the overextended root canal filling material was successful or not. The Fisher's exact test was used to detect any significant difference between the groups (α = 0.05). RESULTS: The success rate for removal of overextended gutta-percha was greater for the Mtwo (30%) and hand files (30%) compared with the ProTaper (20%) and Reciproc (10%). However, no significant statistical differences existed among the experimental groups (P > 0.05). CONCLUSIONS: This study demonstrated that all tested systems had similar efficacy in removing overextended root canal filling material.
Asunto(s)
Instrumentos Dentales , Gutapercha , Materiales de Obturación del Conducto Radicular , Obturación del Conducto Radicular/instrumentación , Preparación del Conducto Radicular/instrumentación , Diente Premolar , Cavidad Pulpar , Humanos , Distribución Aleatoria , Ápice del DienteRESUMEN
AIM: To assess the amount of debris extruded apically during root canal preparation using various nickel-titanium instrumentation systems. METHODOLOGY: Sixty extracted single-rooted mandibular premolar human teeth were randomly assigned to four groups (n = 15 teeth for each group). The canals were then instrumented with the following instrument systems: Vortex Blue (VB; Dentsply Tulsa Dental, Tulsa, OK, USA), K3XF (SybronEndo, Orange, CA, USA), Reciproc (VDW, Munich, Germany) and ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland). Apically extruded debris during instrumentation was collected into pre-weighed Eppendorf tubes. The Eppendorf tubes were then stored in an incubator at 70 °C for 5 days. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and post-instrumentation weight of the Eppendorf tubes for each group. The data were analysed using one-way analysis of variance (anova) and Tukey's post hoc tests. RESULTS: Vortex Blue and PTN files were associated with significantly less apically extruded debris than the K3XF and Reciproc files (P < 0.05), but there was no significant difference between the VB and PTN files or between the K3XF and Reciproc files (P > 0.05). CONCLUSIONS: All instruments were associated with apical extrusion of debris. VB and PTN files were associated with less debris extrusion compared to the other systems.