| 4083 Effect of Loading on Teeth Restored with Post/Core Systems | ||
|
A.A. XIBLE, Sr.1, C.D.R.P.D. ARAUJO2, P.C.R. CONTI2, and D. NATHANSON3, 1Bauru Dental School, Boston University, Brazil, 2Bauru Dental School, Brazil, 3Boston University, USA Objectives: This study compared the residual strength of teeth restored with post systems subjected to thermal and mechanical fatigue. Methods:Sixty extracted canines were endodontically treated with non-eugenol cement (Sealapex – Kerr), and prepared(1.0mm in BL;0.8mm in MD direction; rounded shoulder and 1.5mm dentin ferrule). Teeth were stratified distributed as follow: Groups 1 and 2 were restored with 1.7mm in diameter zirconia posts(Cosmopost–Ivoclar Vivadent) and heat pressed glass-ceramic cores (Empress Cosmo– Ivoclar Vivadent); groups 3 and 4 were restored with 1.5mm in diameter glass fiber posts (FibreKor–Pentron); group 5 and 6 were restored with 1.6mm in diameter titanium posts(AZthec Anchor – Dentatus). Direct resin core build-ups(Build It FR-Pentron) were used for the last four groups. Specimens were restored with all-ceramic crowns(Empress 2–Ivoclar). A resin cement&adhesive system(Cement It&Bond 1 Primer A+B, Pentron) were used to lute the posts and the porcelain crowns. Twenty-four hours after cementing the crowns, the specimens were subjected to 300x thermal cycles, 5 to 550C with 30sec dwell time. Specimens were then embedded with resin acrylic in aluminum blocks. Groups 2, 4 and 6 were subjected to 500.000 cycles of mechanical loading of 250N at a frequency of 1.7Hz. Specimens were subjected to static load in an Instron machine and failure loads were recorded. Data were analyzed using ANOVA and Tukey tests. Results: Group 1(1165,7±210,95 N) was higher than Group 2(886,50±170,62 N);Group 3 (1041,50±231,20 N) was higher than Group 4 (762,20±113,63 N);group 5 (985,40±99,89 N) was higher than group 6 (768,90±72,95 N); Group 1 was higher than the other groups (P<.05). Conclusion:1-Teeth restored with zirconia posts/glass-ceramic cores and not subjected to cyclic fatigue showed the highest resistance to fracture; 2- The fatigue treatment lowered the fracture resistance of all groups tested. Supported by CAPES-Brazil | ||
| Seq #420 - Post/Core Studies, Preparations, Impression Materials, Biomechanics 12:30 PM-2:30 PM, Saturday, 13 March 2004 Hawaii Convention Center 321-B | ||
|
Back to the Prosthodontics Research Program
| ||