Light-Cured Dimethacrylate-Based Resins and Their Composites: Comparative Study of Mechanical Strength,Water Sorption,and Ion Release

Abstract

This study explores how resin type affects selected physicochemical properties of complex methacrylate copolymers and their amorphous calcium phosphate (ACP)-filled and glass-filled composites. Two series of photo-polymerizable resin matrices are formulated employing 2,2-bis[p-(2'hydroxy-3'-methacryloxypropoxy)phenyl]propane (Bis-GMA) or an ethoxylated bisphenol A dimethacrylate (EBPADMA) as the base monomer, unfilled copolymers and composites filled with a mass fraction with 40, 35, and 30%, respectively, of ACP or the un-silanized glass were assessed for biaxial flexure strength (BFS), water sorption (WS), and mineral ion release upon immersion in HEPES-buffered saline solution for up to six months. Substituting EBPADMA for Bis-GMA significantly reduced the WS while only marginally affected the BFS of both dry and wet copolymers. Independent of the filler level, both dry and wet ACP composites formulated with either BTHM or ETHM resins were mechanically weaker than the corresponding copolymers. The BFS of ACP composite specimens after 1 month in saline did not further decrease with further aqueous exposure. The BFS of glass-filled composites decreased with the increased level of the glass filler and the time of aqueous exposure. After 6 months of immersion, the BFS of glass-filled BTHM and ETHM composites, respectively, remained 58 and 41% higher than that of the corresponding ACP composites. Ion release data indicated that a minimum mass fraction of 35% ACP was required to attain the desired solution supersaturation with respect to hydroxyapatite for both the BTHM and ETHM derived composites.

Keywords

amorphous calcium phosphate composites dimethacrylate resins dimethacrylate composites mechanical strength ion release photopolymerization water sorption.

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References

Morgan, D.R. , Kalachandra, S. , Shobha , S. , Gunduz, N. and Stjskal, E.O. (2000). Analysis of a Dimethacrylate Copolymer (Bis-GMA and TEGDMA) Network by DCS and 13C Solution and Solid State NMR Spectroscopy, Biomaterials , 21(18): 1897-1903.

Antonucci, J.M. and Stansbury, J.W. (1997). Molecularly Designed Dental Polymers, Desk Reference of Functional Syntheses and Applications, pp. 719-738, American Chemical Society, Washington DC.

Antonucci, J.M. , Liu, D.W. and Stansbury , J.W. (1993). Synthesis of Hydrophobic Oligomeric Polymers for Dental Applications , J. Dent. Res., 72(IADR Abstracts): 369.

Skrtic, D. , Antonucci, J.M. and Liu, D.W. (2006). Ethoxylated Bisphenol A Methacrylate-based Amorphous Calcium Phosphate Composites, Acta Biomaterialia, 2(1): 85-94.

Skrtic, D. , Antonucci, J.M. and Eanes, E.D. (2003). Amorphous Calcium Phosphate-based Bioactive Polymeric Composites for Mineralized Tissue Regeneration, J. Res. Natl. Inst. Stands. Technol., 108(3): 167-182.

Skrtic, D. , Antonucci, J.M. , Eanes, E.D. , Eichmiller, F.C. and Schumacher, G.E. (2000). Physicochemical Evaluation of Bioactive Polymeric Composites Based on Hybrid Amorphous Calcium Phosphates , J. Biomed. Mater. Res. (Appl. Biomater.), 53B(4): 381-391.

Lee, S.Y. , Regnault, W.F. , Antonucci , J.M. and Skrtic, D. (2007). Effect of Particle Size of an Amorphous Calcium Phosphate Filler on the Mechanical Strength and Ion Release of Polymeric Composites, J. Biomed. Mater. Res., 80B(1): 11-17.

O'Donnell, J.N.R. , Antonucci, J.M. and Skrtic, D. (2006). Amorphous Calcium Phosphate Composites with Improved Mechanical Properties , J. Bioact. Comp. Polym., 21(3): 169-184.

Skrtic, D. and Antonucci, J.M. (2003). Effect of Bifunctional Co-monomers on Mechanical Strength and Water Sorption of Amorphous Calcium Phosphate- and Silanized Glass-filled Bis-GMA-based Composites, Biomaterials, 24(17): 2881-2888.

10.

Antonucci, J.M. , McDonough, W.G. , Liu , D.W. and Skrtic, D. (2002). Effect of Polymer Matrices on Methacrylate Conversion and Mechanical Strength of Bioactive Composites Based on Amorphous Calcium Phosphate, Polymer Preprints, 43(2): 741-742.

11.

Antonucci, J.M. , McDonough, W.G. , Liu , D.W. and Skrtic, D. (2003). Effect of Acidic Comonomers on Methacrylate Conversion and Mechanical Strength of Bioactive Composites Based on Amorphous Calcium Phosphate, Polymeric Materials: Science & Engineering, 88: 50-51.

12.

Skrtic, D. , Antonucci, J.M. , Eanes, E.D. and Eidelman, N. (2004). Dental Composites Based on Hybrid and Surface-modified Amorphous Calcium Phosphates - A FTIR Microspectroscopic Study, Biomaterials, 25(27): 1141-1150.

13.

ASTM F394-78 (re-approved 1996). Standard Test Method for Biaxial Strength (Modulus of Rupture) of Ceramic Substrates.

14.

Nakayama, W.T. , Hall, D.R. , Grenoble , D.E. and Katz, J.L. (1974). Elastic Properties of Dental Resin Restorative Materials, J. Dent. Res., 53(5): 1121-1126.

15.

Vieth, W.R. (1991). Diffusion in and Through Polymers: Principles and Applications, Hanser, Munich .

16.

Soderholm, K.J. (1984). Water Sorption in Bis(GMA)/TEGDMA Resin, J. Biomed. Mater. Res., 18: 271-279.

17.

Kanchanavasita, W. , Anstice, H.M. and Pearson, G.J. (1997). Water Sorption Characteristics of Resin-modified Glass Ionomer Cements, Biomaterials, 18(4): 343-349.

18.

Santos, C. , Clarke, R.L. , Braden, M. , Guitian, F. and Davy, K.W.M. (2002). Water Absorption Characteristics of Dental Composites Incorporating Hydroxyapatite Filler, Biomaterials, 23(8): 1897-1904.

19.

Asaoka, K. and Hirano, S. (2003). Diffusion Coefficient of Water Through Dental Composite Resin, Biomaterials, 24(6): 975-979.

20.

Sideriou, I. , Achilias, D. , Spyroudi , C. and Karabela, M. (2004). Water Sorption Characteristics of Light-cured Dental Resins Based on Bis-EMA/ PCDMA, Biomaterials , 25(2): 367-376.

21.

Palin, W.M. , Fleming, G.J.P. , Burke, F.J.T. , Marquis, P.M. and Randall, R.C. (2005). The Influence of Short and Medium-term Water Immersion on the Hydrolytic Stability of Novel Low-shrink Dental Composites, Dent. Mater., 21(9): 852-863.

22.

Bosh, P. , Fernandez, A. , Salvador, E.F. , Corrales, T. , Catalina, F. and Peinado, C. (2005). Polyurethane-acrylate Based Films as Humidity Sensors, Polymer, 46(26): 12200-12209.

23.

Jacob, M. , Varughese, K.T. and Thomas, S. (2005). Water Sorption of Hybrid Biofiber-reinforced Natural Rubber Biocomposites, Biomacromolecules, 6(6): 2969-2979.

24.

Vogel, G.L. , Chow, L.C. and Brown, W.E. (1983). A Microanalytical Procedure for the Determination of Calcium, Phosphate and Fluoride in Enamel Biopsy Samples, Caries Res., 7: 23-31.

25.

Murphy, J. and Riley, J.P. (1962). Single Solution Method for the Determination of Phosphate in Natural Waters, Anal. Chim. Acta, 27: 31-36.

26.

Antonucci, J.M. and Skrtic, D. (2007). Physicochemical Properties of Bioactive Polymeric Composites: Effects of Resin Matrix and the Type of Amorphous Calcium Phosphate Filler, In: Shalaby, W.S. and Salz, U. (eds), Polymers for Dental and Orthopedic Applications, pp. 217-242, CRC Press, Boca Raton.

27.

Antonucci, J.M. and Skrtic, D. (2005). Matrix Resin Effects on Selected Physicochemical Properties of Amorphous Calcium Phosphate Composites , J. Bioact. Comp. Polym., 20(1): 29-49.

28.

Skrtic, D. and Antonucci, J.M. (2007). Dental Composites Based on Amorphous Calcium Phosphate - Resin Composition/Physicochemical Properties Study, J. Biomat. Appl., 21(4): 375-393.