Eluted substances from unpolymerized and polymerized dental restorative materials and their Nernst partition coefficient.

OBJECTIVES

Components released from resin-based dental materials are important factors in the assessment of the biocompatibility of these materials. The study was performed to investigate the elution of substances from unpolymerized and polymerized composites (Tetric=TET; Arabesk=ARA), ormoceres (Admira)=ADM; Definite=DEF) and the compomere (Hytac=HYT).

METHODS

Specimens were polymerized and immersed in either water or methanol. Besides the unpolymerized specimens were dissolved in methanol. Eluted substances were detected by gas chromatography/mass spectroscopy. The Nernst partition coefficient (DC) of 64 substances, eluted from various resin-based dental materials was determined.

RESULTS

Only in methanolic and aqueous eluates from unpolymerized and polymerized specimens of DEF and ADM, the comonomere 1,2/1,3-glycerol dimethacrylate was measured. Triethylene glycol dimethacrylate was eluted into the aqueous and methanolic phase from polymerized specimens from TET and ARA. 2-Hydroxyethyl methacrylate was eluted into the methanolic phase from polymerized specimen from TET and HYT. Residuals of monomer synthesis like triphenyl stibane were found in unpolymerized specimens of TET and ARA. Camphorquinone was eluted into the methanolic eluate from polymerized and unpolymerized specimens from all tested dental materials. Highest DC of 20.8 was found for 1/2-cyclohexene methacrylate. DC of urethane dimethacrylate and bisphenol-A-glycidyldimethacrylate varies from different manufacturers.

SIGNIFICANCE

Impurities from manufacturing process were found in some resin-based materials. Various well-known substances causing allergic reactions were found in aqueous or methanolic elutes. Patients, dental and manufacturing personnel are exposed to these substances.