The effect of various restoration materials on enamel and dentin of deciduous teeth after long periods in the mouth.

Objectives: Dental restorative materials contain ions that can be released to the surrounding tissues and change the mineral content of enamel and dentin. Glass-ionomer release fluoride to the environment but little is known regarding the effect of amalgam and composite based materials on tooth components.
The objectives of the research were to examine the interactions between different restorative materials and the tooth enamel and dentin in deciduous molars after long periods of function in the mouth.
Methods: 16 normally exfoliated deciduous molars with restorations of amalgam (SDI)- 6 teeth , compomer (Dyract, 3M/ESPE, Germany)- 5 teeth and glass-ionomers (Fuji 9, GC Co., Japan)- 5 teeth were collected . The period that the restorations functioned in the mouth was between 2-5 years (mean 3.82). The teeth were embedded in epoxy and cut bucco-lingually through the occlusal part of the restorations. Using the SEM energy dispersive X-ray spectrometer program, the mineral content of the restorative material, the dentin and the enamel in close contact with the restoration was determined.
Results: Amalgam released significant amount of silver, mercury and copper to the dentin, and less to the enamel. The copper caused color change of the dentin tubules, up to the pulp ceiling. The Dyract had minimal interaction with the enamel or dentin and the amount of fluoride released was minimal. Glass-ionomer released silica, alumina, strontium and fluoride to the enamel and dentin and absorbed calcium and phosphate from the tooth.
Conclusions: Various restorative materials interact differently with the enamel and dentin. Amalgam release metal ions that can reach the pulp through the dentin tubules. Compomers have very small interaction with the tooth components. Glass-ionomers release caries protecting ions to enamel and dentin and absorb calcium and phosphate from the tooth. Regarding the biocompatibility on the restorative materials, glass-ionomers have the best impact on tooth components.