Objective: This in vitro study was to test and compare the effects of two post designs (Flexi-Post and Vlock) in combination with two restorative core materials (silver amalgam (Tytin) and a titanium reinforced composite resin (Ti-Core)) with a metal crown. In vitro fracture loading testing has been a common method of testing a post-core combination. However, there have been limited studies investigating the effects of a crown on the fracture strength of a prefabricated post and core. Methods: This in vitro study consisted of the preparation of 32 tooth/post and core/crown specimens. The specimens were divided into 4 groups and separated according to post and core material used. Metal cast crowns Midas gold (Au)-palladium (Pd) alloy were fabricated for each tooth/post and core combination. Each tooth/post and core/crown combination was placed in a special jig on a 45 degree angle on the buccal/lingual axis and subjected to a load on a universal testing machine (MTS Systems Corp) with a crosshead speed of 0.25 in/min (0.635 cm/min). Results: The values for fractural strength for each group were: group 1=Vlock/Ti-Core 140.8 ± 63.6 pounds; group 2=Flexi-Post/Ti-Core 137.0 ± 59.3 pounds; group 3=Vlock/Tytin 74.1 ± 30.0 pounds; and group 4=Flexi-Post/Tytin 138.8 ± 39.7 pounds. A 2 X 2 factorial two-way analysis of variance (ANOVA) was used to test effects of core material and post type on fracture resistance. All results were considered statistically significant if p < 0.05. Group 3 had statistically lower fractural resistance than groups 1-2 and 4. Groups 1-2 and 4 were all similar to one another. Conclusions: The results for this study were in the same range as other in vitro studies where post and core/crowns were tested for fractural strength.

Back to the Dental Materials: VIII - Others-Non-metallic Program
Back to the 81st General Session of the International Association for Dental Research (June 25-28, 2003)

Top Level Search