Resin-modified glass-ionomers

Resin-Modified Glass—Ionomer Cements. Resin-modified glass—ionomer cements are based on poly(alkeonic acid) systems that have... 

Resin-modified glass—ionomer lining and restorative materials add a multifunctional acidic monomer to the poly(acryhc acid) [9003-01 Hquid component of the system. Once the glass powder and Hquid are mixed, setting can proceed by the acid—glass—ionomer reaction or the added monomer can be polymerized by a free-radical mechanism to rapidly fix the material in place (74,75). The cured material stiH retains the fluoride releasing capabiHties of a glass—ionomer. 

Antonucci, J. M., McKinney, J. E. Stansbury, J. W. (1988). Resin-modified glass-ionomer cement. US Patent Application 160,856. 

Wilson, A. D. (1990). Resin modified glass-ionomer cements. International Journal of Prosthodontics, 3, 425-46. 

Resin-modified glass—ionomer dental cements, 8 283... 

J.F. McCabe, Resin-modified glass ionomers. Biomaterials 19 (1998) 521-527. 

Resin-modified glass-ionomers, like their conventional counterparts, are capable of releasing fluoride [224,264,265], and in greater amounts under acid conditions than neutral ones [265], Release rates and release profiles have been shown to be comparable with those from conventional glass-ionomer cements [264,265], Other ions have also been shown to be released by these materials and, as for fluoride, these ions show a greater release under low pH conditions [265], However, the level of phosphorus released has been shown to be much lower from resin-modified glass-ionomers than from conventional ones [263], This suggests that there is little or no possibility of association of fluoride as monofluorophosphate, but rather that almost all of the fluoride is released either as the free fluoride ion or as alumino-fluoride complex ions. 

R.M.H. Verbeeck, E.A.P. De Maeyer, L.A.M. Marks, R.G.J. De Moor, A.M.C.J. De Witte, L.M. Trimpeneers, Fluoride release process of (resin-modified) glass-ionomer cements versus (polyacid-modified) composite resins. Biomaterials 19 (1998) 509-519. 

J.A. Williams, R.W. Billington, G.J. Pearson, A long term study of fluoride release from metal containing conventional and resin modified glass ionomer cements, J. Oral Rehabil. 28 (2001) 41 7. 

B. Czarnecka, J.W. Nicholson, Ion release by resin-modified glass-ionomer cements into water and lactic acid solutions, J. Dent. 34 (2006) 539-543. 

Glas-ionomer cements are acid-based materials (using, e.g., polyacrylic acid), whose setting reaction involves neutralization of the acid groups by powdered solid bases (calcium fluoro-aluminosilicate glasses). Resin-modified glass ionomer cements are hybrid materials prepared by the incorporation of polymerizable components such as 2-hydroxyethyl methacrylate. ... 

Use of resin-modified glass-ionomers has grown considerably since their introduction in 1991, and versions are available that are suitable for use as full restorations [34]. However, because of limited penetration by light, deep cavities may need to be filled using the incremental build-up technique usually associated with composite resins. Resin-modified glass-ionomers show good adhesion to dentine [31] and also release useful amounts of fluoride [31,35]. 

Despite these occasional alternative names for these materials, the term resin-modified glass-ionomer seems to have become the most widely used of them all. It is the one that most manufacturers favour in describing their products, and is also the one used most extensively in the scientific and clinical literature. Because of its scientific accuracy [6], it is our preferred term and the one we apply to these materials throughout the current book. 

This means that polyacid-modified composites are essentially composite resins. As such, they must be bonded to the tooth with appropriate bonding agents, applied in increments, and show no ion-exchange properties, though they will release fluoride [38]. Similarly, resin-modified glass-ionomers are very similar to conventional glass-ionomers. They show inherent adhesion to the tooth [30], long-term fluoride release [31] and ion-release under neutral and acidic conditions [59]. 

S.K. Sidhu, Clinical evaluations of resin-modified glass-ionomer restorations. Dent. Mater. 26 (2010) 7-12. 

The amount of fluoride released by composites tends to be much lower than that released by either conventional or resin-modified glass-ionomer. It is also lower than the level released by polyacid-modified composite resins. The reason for this is not... 

As with glass-ionomer cements, flnoride release from polyacid-modified composite resins is snstained for long periods of time [23] and is enhanced by placing the polyacid-modified composite resin in acidic storage media [25,36]. This property has been snggested to be beneficial in the case of resin-modified glass-ionomers [37], since it wonld lead to enhanced release of protective fluoride ion under the very conditions that promote dental caries. A similar argnment can be advanced for polyacid-modified composite resins, and it may be that this ability to release extra fluoride under conditions of low pH is beneficial clinically. 

V. Qvist, L. Laurheig, A. Poulsen, P.T. Teglers, Class II restorations in primary teeth 7-year study on three resin-modified glass ionomer cements and a compomer. Fur. J. Oral Sci. 112(2004) 188-196. 

M. A. Chinelatti, R.P. Ramos, D.T. ChimeUo, R.G. Pahna-Dibb, Clinical performance of a resin-modified glass-ionomer and two polyacid-modified resin composites in cervical lesions restorations 1-year follow-up, J. Oral Rehabil. 31 (2004) 1-7. 

A.D. Lognercio, A. Reis, A.N. Barbosa, J.F. Ronlet, Five-year double-blind randomized clinical evaluation of a resin-modified glass ionomer and a polyacid-modified resin in noncarious cervical lesions, J. Adhes. Dent. 5 (2003) 323-332. 

R.J. Smales, K.K.W. Ng, Longevity of a resin-modified glass ionomer cements and a polyacid-modified resin composite restoring non-carious cervical lesions in general dental practice, Aust. Dent. J. 49 (2004) 196-200. 

M. Folwaczy, A. Mehl, K.H. Knnzelmann, R. Hickel, Chnical performance of a resin-modified glass-ionomer and a compomer in restoring non-carious cervical lesions. 5-year results. Am. J. Dent 13 (2001) 153-156. 

W. Gao, R.J. Smales, Fluoride release/uptake of conventional and resin-modified glass-ionomers and compomers, J. Dent. 29 (2001) 301-306. 

B. Van Meerbeek, Y. Yoshida, S. Inoue, R. Fukada, M. Okazaki, P. Lambrechts, G. Vanherle, Interfacial characterization of resin-modified glass-ionomers to dentin,... 

Having established the essential features of resin-modified glass-ionomers, in the rest of the chapter we consider their composition, properties and clinical applications in modem clinical practice. 

The essential feature of resin-modified glass-ionomers is that they include polymerizable components with an acid-base system [2-4]. They therefore comprise a complex blend of components, as follows ... 

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