Fracture resistance of a new fiber post design

Abstract

AIM or PURPOSE The aim of this study was to design and develop new prefabricated fiberglass posts, compare their fracture resistance with those of a metal cast post and a traditional prefabricated fiberglass post, and identify the types of failures. MATERIALS and METHOD An in vitro study was carried out employing a new post designed from a conventional prefabricated fiberglass post with a modification in the apical third, consisting of an “anchor” 3 mm high. One hundred fifty-eight extracted teeth received conventional endodontic treatment and were randomly assigned to six experimental groups. For the canal walls preparation the ParaPost® Taper Lux® drills was used. The teeth were cut at the cement-enamel junction to standardize the length (15 mm). The specimens were tested for failure resistance using a universal testing machine at 90° at 0.5 mm/min until failure. The failure mode of the specimens was also evaluated with a stereomicroscope at 40x magnification. The data obtained were analyzed with two-way ANOVA and Tukey's DSH tests (p=0.05). RESULTS Regarding the type of tooth (anterior-posterior), there was no statistically significant difference (p=0.66). The fracture resistance (Newtons) of metal cast posts was different from those of prefabricated fiberglass posts (p=0.000) and anchor prefabricated fiberglass posts (p=0.000). Regarding the failure mode, a longitudinal root fracture was exhibited in most of the specimens of prefabricated fiberglass posts and anchor fiberglass posts. CONCLUSION(S) The new anchor prefabricated fiberglass post tries to unite the retentive characteristics of the metal cast post and the advantages of the elastic modulus of the prefabricated fiber post.