Abstract
OBJECTIVE: To assess the mechanical properties of discrete filler particles representative of several inorganic fillers in modern dental resin-based composites (RBCs) and to assess the validity of a novel micromanipulation technique. METHOD: RBCs with microhybrid (Filtek Z250), 'nanohybrid' (Grandio) and 'nanofilled' (Filtek Supreme), filler particle morphologies were investigated. Filler particles were provided by the manufacturer or separated from the unpolymerized resin using a dissolution technique. Filler particles (n=30) were subjected to compression using a micromanipulation technique between a descending glass probe and a glass slide. The number of distinct fractures particles underwent was determined from force/displacement and stress/deformation curves and the force at fracture and pseudo-modulus of stress was calculated. RESULTS: Agglomerated fillers ('nanoclusters') exhibited up to four distinct fractures, while spheroidal and irregular particles underwent either a single fracture or did not fracture following micromanipulation. Z-tests highlighted failure of nanoclusters to be significant compared with spheroidal and irregular particles (P
Original language | English |
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Pages (from-to) | 180-7 |
Number of pages | 8 |
Journal | Dental Materials |
Volume | 25 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1 Feb 2009 |
Keywords
- Nanofillers
- Micromanipulation
- Filler particle
- Resin-based composite