A Novel Nano-Ionomeric Restorative with Improved Polish and Wear-Resistance

Objective:  The goal of this study was to compare the polish and wear properties of Ketac Nano, a nano-ionomeric glass ionomer, with several commercial resin-modified glass ionomeric (RMGI) and hybrid composite restorative products.  The restoratives evaluated included three commercial RMGI materials: Fuji II LC (FIILC, GC), Fuji Filling LC (FFLC, GC), Ketac Nano (KN, 3M ESPE), and a hybrid composite Tetric Evo Ceram (TEC, Ivoclar Vivadent).  FIILC is a powder/liquid-based system while FPP and KN are paste/paste.  Method:  All materials were mixed and light-cured per manufacturers' recommendation. Samples were polished per a clinically relevant procedure using commercial finishing/polishing systems.  The gloss of multiple samples was measured immediately after polishing using a gloss meter at 60 degrees.  Three-body wear depth was measured after 80,000 cycles according to ACTA Protocol.  Multiple specimens of each material per test protocol were prepared and immersed in 37C deionized water for 24 h before testing.  Results:  Atomic Force Microscopy (AFM) pictures of polished samples will be presented.  The mean values including their standard deviations in the parentheses are summarized in the following table:

Restorative	Chemistry	Format	Wear Depth after 80k cycles, micron	Initial Polish Number
Ketac Nano (KN)	RMGI	Paste/Paste            hand-mixed	21.8(1.3)	36.5(1.3)
Fuji II LC (FIILC)	RMGI	Powder/Liquid    capsule & hand-mixed	32.6(0.8)	3.4(0.6)
Fuji Filling LC (FFLC)	RMGI	Paste/Paste             hand-mixed	52.7(1.2)	2.4(0.4)
Tetric Evo Ceram (TEC)	Hybrid Composite	One part Paste	6.8(0.4)	64.2(11)

Conclusions:  ANOVA with Tukey's comparison was performed at p < 0.05.  Ketac Nano paste/paste nano-ionomeric restorative (KN) showed significantly higher gloss compared to other RMGIs, closer to that of a hybrid composite.  Ketac Nano paste/paste nano-ionomer (KN) had significantly lower wear rate compared to other RMGIs.