Variability in Cytotoxicity and Fluoride Release of Resin-modified Glass-ionomer Cements

Abstract

New-generation glass-ionomer cements contain resin to improve their restorative properties. These resin-modified glass-ionomer cements vary considerably in their chemistry, which could result in corresponding variability in their physical and biological properties. This study investigated the cytotoxicity and the fluoride release of two resin-modified glass ionomers, a conventional glass-ionomer cement, and a resin composite. Samples were prepared and extracted in distilled water for 1, 4, and 7 days; eluates were filtered and tested by means of 3T3 mouse fibroblasts. Cytotoxicity (MTT assay) values were low for all materials and extraction times, indicating minimal cytotoxicity of all materials (less than 30% inhibition). Cytotoxicity of one resin-modified glass ionomer was significantly higher than for the other materials (p < 0.001). One resin-modified glass ionomer and the conventional glass-ionomer cement released significantly more fluoride at each time interval (p < 0.001) than the other resin-modified glass-ionomer cement and the resin composite. Fluoride release and cytotoxicity were correlated (r ² = 0.60; p < 0.001), although the fluoride release does not account for the cytotoxicity observed. Cytotoxicity and fluoride release suggest that one hybrid behaved more like a conventional glass ionomer, and the other like a resin composite. These differences may have implications for material selection in specific clinical situations.

Keywords

in vitro cytotoxicity fluoride release glass-ionomer cements.

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References

Bapna MS , Mueller HJ (1994). Leaching from glass-ionomer cements. J Oral Rehabil 21:577-583.

Cao DS , Hollis RA , Hicken CB , Christensen RP (1994). Fluoride release from glass ionomers, glass iono-mer/resins and composites (abstract). J Dent Res 73:657.

Caughman WF , Caughman GB , Dominy WT , Schuster GS (1990). Glass ionomer and composite resin cements: Effects on oral cells. J Prosthet Dent 63:513-521.

Chadwick SM , Gordon PH (1995). An investigation into the fluoride release of a variety of orthodontic bonding agents. Br J Ortho 22:29-33.

Edmondson JM , Armstrong LS , Martinez AO (1988). A rapid and simple MTT-based spectrophotometric assay for determining drug sensitivity in monolayer cultures. J Tissue Cult Meth 11(1):15-17.

Fischman SA , Tinanoff N. (1994). The effect of acid and fluoride release on the antimicrobial properties of four glass ionomer cements. Pediatr Dent 16:368-370.

Forsten L. (1995). Resin-modified glass ionomer cements: fluoride release and uptake. Acta Odontol Scand 53:222-225.

Hanks CT , Strawn SE , Wataha JC , Craig RG (1991). Cytotoxic effects of resin components on cultured mammalian fibroblasts. J Dent Res 70:1450-1455.

Hatibovic-Kofman S. , Koch G. ( 1991). Fluoride release from glass ionomer cement in vivo and in vitro. Swed Dent J 15:253-258.

10.

Kasugai S. , Hasegawa N. , Ogura H. (1990). A simple in vitro

11.

cytotoxicity test using the MTT (3-(4,5)-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) colorimetric assay: analysis of eugenol toxicity on dental pulp cells (RPC-C2A). Jpn J Pharmacol 52:95-100.

12.

Kasugai S. , Hasegawa N. , Ogura H. (1991). Application of the MTT colorimetric assay to measure cytotoxic effects of phenolic compounds on established rat dental pulp cells . J Dent Res 70:127-130.

13.

Kawahara H. , Imanishi Y. , Oshima H. (1979). Biological evaluation on glass ionomer cement . J Dent Res 58:1080-1086.

14.

Lefebvre CA , Schuster GS (1994). Biocompatibility of visible light-cured resin systems in prosthodontics. J Prosthet Dent 71:178-185.

15.

Loyola-Rodriguez JP , Garcia-Godoy F. , Lindquist R. (1994). Growth inhibition of glass-ionomer cements on mutans streptococci. Pediatr Dent 16:346-349.

16.

Matsuya S. , Matsuya Y. , Yamamoto Y. , Yamane M. (1984). Erosion process of a glass ionomer cement in organic acids. Dent Mater J 3:210-219.

17.

McKnight-Hanes C. , Whitford GM (1992). Fluoride release from three glass ionomer materials and the effects of varnishing with or without finishing. Caries Res 26:345-350.

18.

Miller BH , Komatsu H. , Nakajima H. , Okabe T. (1995). Effect of glass ionomer manipulation on early fluoride release. Am J Dent 8:182-186.

19.

Mitra S. (1994). Curing reactions of glass ionomer materials. In: Glass ionomers: The next generation. Proceedings of the Second International Symposium on Glass Ionomers, June, 1994, Philadelphia, PA. Hunt PR, editor. International Symposia in Dentistry, PC, pp. 13-22.

20.

Momoi Y. , McCabe JF (1993). Fluoride release from light-activated glass ionomer restorative cements. Dent Mater 9:151-154.

21.

Mosmann T. (1983). Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays. J Immunol Meth 65:55-63.

22.

Muller J. , Bruckner G. , Kraft E. , Horz W. ( 1990). Reaction of cultured pulp cells to eight different cements based on glass ionomers. Dent Mater 6:172-177.

23.

Musa A. , Pearson GJ , Gelbier M. (1996). In vitro investigation of fluoride ion release from four resin-modified glass polyalkenoate cements. Biomaterials 17:1019-1023.

24.

Peltola M. , Salo T. , Oikarinen K. (1992). Toxic effects of various retrograde root filling materials on gingival fibroblasts and rat sarcoma cells. Endod Dent Traumatol 8:120-124.

25.

Ratanasathien S. , Wataha JC , Hanks CT , Dennison JB (1995). Cytotoxic interactive effects of dentin bonding components on mouse fibroblasts. J Dent Res 74:1602-1606.

26.

Takahashi K. , Emilson CG , Birkhed D. (1993). Fluoride release in vitro from various glass-ionomer cements and resin composites after exposure to NaF solutions. Dent Mater 9:350-354.

27.

Wilson AD (1990). Resin-modified glass-ionomer cements. Int J Prosthodont 3:425-429.

28.

Wilson AD , Groffman DM , Kuhn AT ( 1985). The release of fluoride and other chemical species from a glass-ionomer cement. Biomaterials 6:431-433.