Fracture resistance and reliability of new zirconia posts

摘要: Abstract Statement of problem The radicular portion zirconia endodontic posts often need to be reshaped achieve a definitive form and may airborne-particle abraded improve adhesion during luting. Therefore, the surface tetragonal ceramics transformed damaged, influencing mechanical properties material. Purpose This study compared fracture resistance prefabricated with new retentive post-head after different treatments. Material methods Experimental 2 diameters, 1.3 mm 1.5 mm, were produced from commercially available powder. A cylindro-conical outline was used for root system 3 rings designed. Sixty each diameter divided into groups (n=20). Group 1 ground coarse grit diamond bur; 110-μm fused alumina particles, left as-received (controls). Posts luted root-shaped artificial canals Clearfil adhesive Panavia 21 resin luting agent. loaded in universal testing machine at an inclination 45 degrees constant cross-head speed mm/min. load (N) necessary cause post recorded, statistical significance differences among analyzed 1-way ANOVA followed by Fischer LSD test (α=.05). variability using Weibull statistics. Results Load values all depended primarily on diameter. Mean loads (SD) Newtons 518.4 (±101.3), 993.6 (±224.1), 622.7 (±110.3) Groups through 3, respectively, thicker posts, 385.9 (±110.3), 627.0 (±115.1), 451.2 (±81.4) thinner posts. Airborne-particle-abraded exhibited significantly higher ( P Conclusion Within limitations this study, results suggest that grinding leads significant drop whereas abrasion increased load.