Organic leachables from dental materials

Organic leachables from resin-based dental restorative and prosthetic materials.

Main content

During the last decade resin-based dental restorative materials has replaced amalgam as the first choice dental filling material. The resin-based dental restorative materials are complex polymers containing a variety of monomers, inorganic filler particles as well as initiators, activators, stabilizers, plasticizers and other additives. The polymerization is found to be incomplete and several studies have shown that many of the ingredients are leaching from the filling materials even after adequate polymerization. It is known from in vitro studies that some of the ingredients in the resin-based materials have cytotoxic, genotoxic or estrogenic potential. Allergenic effects in patients and dental personal has also been reported.
The aim of the study is to identify and quantify substances released from several resin-based dental restorative materials. Specimens made from the materials are cured according to the producers and immersed in different immersion media. To characterize a maximum elution potential ethanol is used as an immersion media. Furthermore, immersion in water, Ringer's solution and saliva is used to mimic more realistic elution conditions.
For identification and quantification of the eluates we use a gas chromatograph (GC) combined with a mass spectrometer (MS). The majority of the eluting substances from the polymeric phase are organic substances with low molecular weight, which are well suited for analysis by GC-MS. Tailor-made internal standards have been synthesized for the quantification procedure of the eluates.
We have identified and quantified a number of compounds from several materials. Significant differences regarding type and amount of leachables between the materials are observed.
Further studies will address the in vivo situation by collecting samples of saliva from patients who receive resin-based fillings, and identify and quantify eluted substances.

Vibeke Barman Michelsen