Adhesion, resin-modified glass-ionomers

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]. 

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]. 

Resin-modified glass-ionomers are adhesive to both enamel and dentine. 

A wide range of repairs is possible with resin-modified glass-ionomers, and they can also be used as hners and bases, and as orthodontic adhesives. 

P. Wangpermtam, M.G. Botelho, J.E. Dyson, Effect of contamination and decontamination on adhesion of a resin-modified glass-ionomer cement to bovine dentin, J. Adhes. Dent. 13 (2011)445 53. 

V.V. Gordan, D. Bover, K. Soderhohn, Enamel and dentine shear bond strength of two resin modified glass ionomers and two resin based adhesives, J. Dent. 26 (1998)... 

L. Wang, V.T. Sakai, E.S. Kawai, M.A. Buzalaf, M.T. Atta, Effect of adhesive systems associated with resin-modified glass ionomer cements, J. Oral Rehahil. 33 (2006) 110-116. 

P.N.R. Periera, T. Yamada, S. Inokoshi, M.F. Burrow, H. Sano, J. Tagami, Adhesion of resin-modified glass ionomer cements using resin bonding systems, J. Dent. 26 (1998) 479-486. 

S.B. Mitra, C.-Y. Ling, H.T. Bui, D. Tantbiroin, R.P. Rusin, Long-term adhesion and mechanism of bonding of a paste-liquid resin-modified glass-ionomer. Dent. Mater. 25 (2009) 459-466. 

The enhanced performance resin-modified glass-ionomers are high in resin, and as a result appear to have somewhat compromised adhesion. Their bioactivity appears very good. Considerable further work is required to know whether or not these materials represent a significant advance in glass-ionomer technology and restorative dentistry. 

One of the key features of polyacid-modified composite resins is their lack of adhesion to tooth tissnes [5]. This is a feature that they share with conventional dental composite resins, and the contrasts with the behaviour of the glass-ionomer cement. It is further evidence that these materials are essentially composite resins, and have very little of the anticipated hybrid character of composites and glass-ionomers. Bonding therefore reqnires the type of bespoke bonding agents used for conventional composite resins, together with the appropriate preparation of the freshly cut tooth surface [6]. 

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