Journal of Dental Research, Vol 76, 1405-1411, Copyright © 1997 by International & American Associations for Dental Research Online Journals

ARTICLES

In vitro wear of composite with varied cure, filler level, and filler treatment

J. R. Condon and J. L. Ferracane
Department of Biomaterials and Biomechanics, School of Dentistry, Oregon Health Sciences University, Portland 97201, USA.

For the clinical wear of composite filing materials to be reduced, compositional factors such as degree of cure, filler level, and silanation level should be optimized. An oral-wear-stimulating machine was used to explore the effects of these factors on abrasion and attrition wear as well as on opposing enamel wear. The composites were made from Sr glass (1-2 micron avg) and a 50/50 Bis-GMA/TEGDMA resin. Series I (A-D, E) were light-cured (Triad II) for 9, 12, 25, and 40 sec/side to produce degree of cure (DC) as measured by FTIR of 56, 60, 61, and 63%, respectively. E received an additional heat cure (120 degrees C for 10 min) to reach a DC of 66%. Series II (D, F-I) were filled to 62, 53, 48, 37, and 28 vol%, respectively. In series III (D, J-M), the portion of fillers treated with a silane coupler (MPS) was 100, 80, 60, 40, and 20%, respectively. Samples were cycled 50,000 times against an enamel antagonist in a poppy seed/PMMA slurry in the oral wear simulator to produce abrasion (load = 20 N) and attrition (load = 70 N) simultaneously. Wear depth (micron: n = 5) was measured by profilometry. Results for each series were analysed by ANOVA/Turkey's (p < or = 0.05). The wear depths did reflect cure values, though only the abrasion difference for E < A was significant. Greater wear was correlated with lower filler levels (r2 = 0.88; p < 0.05), significantly increasing below 48 vol% (G). Wear increased linearly as the percent of silane-treated fillers was reduced (r2 = 0.99; p < 0.05). Abrasion and attrition did not differ significantly for any composite. Wear of the opposing enamel was largely unchanged by these factors. Compositional factors including degree of cure, filler level, and silanation directly affected the wear resistance of dental composites evaluated in an oral wear simulator.

This article has been cited by other articles:

				J.L. Drummond Degradation, Fatigue, and Failure of Resin Dental Composite Materials J. Dent. Res., August 1, 2008; 87(8): 710 - 719. [Abstract] [Full Text] [PDF]

				A. Faltermeier, M. Rosentritt, R. Faltermeier, and D. Mussig Influence of fibre and filler reinforcement of plastic brackets: an in vitro study Eur J Orthod, June 1, 2007; 29(3): 304 - 309. [Abstract] [Full Text] [PDF]

				J.P. Matinlinna, L.V.J. Lassila, I. Kangasniemi, and P.K. Vallittu Isocyanato- and Methacryloxysilanes Promote Bis-GMA Adhesion to Titanium J. Dent. Res., April 1, 2005; 84(4): 360 - 364. [Abstract] [Full Text] [PDF]

				H.H. K. Xu, J.B. Quinn, and A.A. Giuseppetti Wear and Mechanical Properties of Nano-silica-fused Whisker Composites J. Dent. Res., December 1, 2004; 83(12): 930 - 935. [Abstract] [Full Text] [PDF]

				R. R. BRAGA, T. J. HILTON, and J. L. FERRACANE Contraction stress of flowable composite materials and their efficacy as stress-relieving layers J Am Dent Assoc, June 1, 2003; 134(6): 721 - 728. [Abstract] [Full Text] [PDF]

				J. R. CONDON and J. L. FERRACANE ASSESSING THE EFFECT OF COMPOSITE FORMULATION ON POLYMERIZATION STRESS J Am Dent Assoc, April 1, 2000; 131(4): 497 - 503. [Abstract] [Full Text] [PDF]