fracture strength of teeth restored with fiber post and apical plug

Introduction: the aim of this study was to assess the fracture strength of immature single-rooted teeth restored with fiber post and apical plug. materials &methods: in this experimental study, fifty mandibular premolars were divided into five groups. the coronal and apical portions were cut to obtain15±1 mm root lengths and cleaning &shaping were performed. peeso reamer #4 was passed the apex by 1 mm to simulate an immature tooth and the apical portion in group 1 to 5 was filled by lateral compaction of 5 mm of gutta-percha; 5 mm of mineral trioxide aggregate (mta); 5mm of calcium enriched mixture (cem) cement; 3 mm of mta and 2 mm of gutta-percha by vertical condensation and 3 mm of cem cement and 2 mm of gutta-percha, respectively. the remaining portion was restored with glass fiber post and self-etch cement and composite cores were built. compressive load was applied at a crosshead speed of 1 mm/minute at 90 ° angle until fracture in a universal testing machine. data were analyzed using anova in spss16. results: the mean±sd fracture strength was recorded 607.8±162.41 n, 700.48±183.24 n, 595.16±171.77 n, 886.36±382.92n, and 868.87±440.36 n in groups one to five, respectively. no significant difference was observed among the experimental groups (p=0.1). conclusion: in immature teeth requiring an apical plug, fiber post can be placed directly on the mta and cem apical plugs and there is no need for placing gutta-percha on the plug.