Flexural Strengths of Implant-Supported Zirconia Based Bridges in Posterior Regions Publisher



Rismanchian M¹ ; Shafiei S² ; Nourbakhshian F³ ; Davoudi A³
Source: Journal of Advanced Prosthodontics Published:2014

Abstract

Purpose: Impact forces in implant supported FDP (fixed dental prosthesis) are higher than that of tooth supported FDPs and the compositions used in frameworks also has a paramount role for biomechanical reasons. The aim of this study was to evaluate the flexural strength of two different zirconia frameworks. Materials and methods: Two implant abutments with 3.8 mm and 4.5 mm platform were used as premolar and molar. They were mounted vertically in an acrylic resin block. A model with steel retainers and removable abutments was fabricated by milling machine; and 10 FDP frameworks were fabricated for each Biodenta and Cercon systems. All samples were thermo-cycled for 2000 times in 5-55°C temperature and embedded in 37°C artificial saliva for one week. The flexural test was done by a rod with 2 mm ending diameter which was applied to the multielectromechanical machine. The force was inserted until observing fracture. The collected data were analyzed with SPSS software ver.15, using Weibull modulus and independent t-test with the level of significance at α=.05. Results: The mean load bearing capacity values were higher in Biodenta but with no significant differences (P > .05). The Biodenta frameworks showed higher load bearing capacity (F0=1700) than Cercon frameworks (F0=1520) but the reliability (m) was higher in Cercon (m=7.5). Conclusion: There was no significant difference between flexural strengths of both zirconia based framework systems; and both Biodenta and Cercon systems are capable to withstand biting force (even parafunctions) in posterior implant-supported bridges with no significant differences. © 2014 The Korean Academy of Prosthodontics.