ABSTRACT
Reasons for the failed endodontic teeth which had an extensive restoration can be attributed to the multiple materials that were used in it. Various post-core materials that are commonly used are compared for fracture resistance in the current study. Fourty maxillary incisors that needed root canal therapy were allocated into four groups of 10 each. Using adhesive resin cement, teeth were repaired in three experimental groups with ceramic fiber post, glass post, and stainless steel post. All these posts with composite post and core. Samples that still had their coronal structure were considered as controls that were without any post-cores. Every sample was ready for the best abutment preparation. Using the universal testing machine, all the specimens were examined for the compressive strength at 130° until fracture was experienced. The data for the force levels at which the fracture occurred were noted and compared for significance using analysis of variance (ANOVA), keeping P < 0.05 as significant. The fracture resistance values were significantly variable among all the groups, with P < 0.05. The stainless steel post exhibited the highest strength before it succumbed to the fracture. The glass posts showed better restorability and were esthetically acceptable. The least fracture resistance was demonstrated by teeth that had no post-core, highlighting the necessity of strengthening the tooth. Among all the experimental groups, the one that demonstrated the highest fracture resistance was composite core and steel posts.
ABSTRACT
Introduction and Aim: Postoperative inflammation and endodontic failure occur due to apical extrusion of debris. The purpose of this in vitro study was to assess the amount of apically extruded debris during the root canal preparation using rotary and reciprocating nickel-titanium instrumentation systems. Materials and Methods: The mesiobuccal canals of seventy five mature, human mandibular molars were randomly divided into three groups (n = 25 teeth/group). Each group was instrumented using one of the three different instrumentation systems: Hyflex EDM (HEDM) rotary file, Flexicon X7 rotary, and Flexicon X1 reciprocating files. The canals were irrigated using distilled water. The debris extruded apically was collected in preweighed Eppendorf tubes and assessed with an electronic balance and compared. Statistical Analysis: Data were statistically analyzed by one-way analysis of variance and the intergroup comparison with single factor ANOVA. Results: The Flexicon X1 reciprocating system showed the maximum amount of apical extrusion of debris among all the groups. The least amount of debris was observed in Flexicon X7 rotary instrument (P > 0.05). Conclusion: Flexicon X7 rotary extruded significantly lesser amount of debris than Flexicon X1 reciprocating and HEDM rotary file systems.
