Effect of particle variation on wear rates of posterior composites.
OBJECTIVE
To evaluate the relationship between filler size, shape, mechanical properties and wear resistance of posterior resin composite was evaluated.


METHODS
Six UDMA/TEGDMA-based experimental resin composites consisting of different types of filler particles were investigated. These included four sized spherical fillers, (9.88 microns, 2.01 microns, 0.62 micron, 0.20 micron) and two irregular, (9.46 microns, 1.97 microns). Property measurements consisted of hardness and compressive strength. Wear resistance was evaluated by a three-bodied in vitro wear test.


RESULTS
The composites containing the smallest sized spherical particle exhibited maximum mechanical strength and maximum wear resistance. The composites containing the largest spherical particle exhibited minimum wear resistance. There were no significant differences amongst those containing similar sized fillers regardless of particle shape. However, differences between the 0.20 microns spherical filled composite and other composites were statistically significant. SEM analysis showed that only the larger sized filler exhibited some exfoliation after wear testing. The smaller size spherical filler exhibited better mechanical strength and substantially higher wear resistance.
Suzuki
S
S
Department of Biomaterials, UAB School of Dentistry, Birmingham 35294-0007, USA.
Leinfelder
K F
KF
Kawai
K
K
Tsuchitani
Y
Y
D000704:Analysis of Variance; D001641:Bicuspid; D003188:Composite Resins / Q000737:chemistry*; D003793:Dental Restoration, Permanent; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D008963:Molar; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D013499:Surface Properties
D003188:Composite Resins; D008689:Methacrylates; D011109:Polymethacrylic Acids; D011140:Polyurethanes; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols