IADR Abstract Archives

A novel indentation approach for mechanical characterization of dental composites

Objectives: The aim of this research was to determine the elastic (modulus, E), plastic (hardness, H) and fracture toughness (K1c) of resin-based dental composite restoratives using a single test platform based on the depth-sensing indentation technique. Materials: The materials investigated were from the same manufacturer (3M ESPE) and included minifill (Z100 and Filtek Z250), microfill (A110), poly-acid modified (F2000), and flowable (Filtek Flow [FF]) composites. Methods: Seven specimens (3 x 3 x 2 mm3) were prepared for each material. They were polished to 1 µm finishes and conditioned in distilled water at 37 °C for one week prior to the indentation testing. Corner cube (54.7° face angle) indenter was employed and a peak indentation load of 5 N was used to determine the E and H of the materials. A higher indentation fracture load of between 20 N to 100 N was used to initiate the crack in calculating the K1c. Data was analyzed using ANOVA/post-hoc Scheffe's tests at a significance level of 0.05. Results: The E and H of the materials ranged from 5.16 to 13.27 GPa and 0.58 to 1.02 GPa respectively. Ranking for E and H were Z100 & F2000 > Z250 > FF & A110 and Z100 > Z250 & F2000 > A110 > FF respectively. The rankings were in agreement with results using conventional test methods. K1c of the materials ranged from 0.56 to 0.94 MPa.m1/2. Ranking of fracture resistance to crack propagation was as follows: Z250 > F2000, Z100 & FF > A110. Conclusions: Due to its simplicity and good reproducibility, the indentation technique is as a more time and cost effective method for the screening of resin-based dental composite restoratives. This study was supported by NUS Research Grant R-224-000-014-112.


Division: Southeast Asian Division Meeting
Meeting: 2004 Southeast Asian Division Meeting (Koh Samui, Thailand)
Location: Koh Samui, Thailand
Year: 2004
Final Presentation ID: 63
Abstract Category|Abstract Category(s): Scientific Groups
Authors
  • Chung, Sew Meng  ( National University of Singapore, Singapore, N/A, Singapore )
  • Yap, Adrian U Jin  ( National University of Singapore, Singapore, N/A, Singapore )
  • SESSION INFORMATION
    Oral Session
    Dental Materials: V - Polymer Materials
    09/05/2004