Determination of leachable compoments from dual-cured resin luting cements

Objectives:

The purpose of this study was to determine the quality and quantity of leachable residual monomers from three various commercial dual cured resin luting cements after polymerization.

Methods:

Dual-cured resin luting cements, obtained from different manufacturers and containing a variety of monomers, were chosen for this investigation ( Panavia F 2, - Kuraray Medical Tokyo, Japan, Variolink 2 - Ivoclar, Vivadent Lichtenstein and Nexus 2 - (Kerr Corporation).

The five specimens of each material were prepared in accordance with manufacturers instructions

After mixing luting cements were placed into stainless steel ring mould ( thickness 1mm, diameter 8mm) and were hardened by an external light sours in five sections for 20 sec .During polymerization all specimens were fully covered by transparent plastic matrix strips, in order to prevent the formation an air – inhibited surface layer. Immediately after curing, the samples were stored in water for 24 hours at 37°C.After extraction the resulting solutions were analyzed by HPLC.

Results:

The monomer TEGDMA was the main substance found in storage water for the materials Nexus 2 and Variolink 2. The highest amount of estrogenic compound Bisphenol A was released from Panavia F2. Significant concentrations of HEMA were eluted from Nexus 2. The monomer UDMA could not be detected in the storage water for the material Panavia F2. There is statistically high significant difference in values of leachable monomers between the examined materials (p< 0,001).

Conclusion:

From the results of this experiment it can be concluded that resin luting cements can release a high quantity of monomer in aqueous environment.