Stomatologic materials biotesting in vitro

Aim. To clarify the specific influence of an adhesive system («Single Bond Universal») on contents, physical and chemical parameters of oral liquid to confirm its safety for use in common dental practice. Methods. A series of in vitro experiments of 5 and 20 seconds of 3 ml oral liquid photopolymerization of 23 dentally and generally healthy subjects aged 18-25 years were performed. Salivary acidity (pH), redox potential, structure, absorption specters, membrane toxicity parameters were assessed. Results. An adhesive system shifted the pH to 6.02±0.21, changed the balance of oxidized and reduced substances with redox potential shift without influencing on salivary structuring. «Filtek Ultimate» and «Filtek Bulk Fill» nanocomposites did not altered the acid-base balance, pH was stable and within the control ranges, redox potential was significantly reduced, mainly by «Filtek Ultimate» (3.6 times lower compared to control parameters), it has also increased the oral liquid structuring by 22,7%. Adhesive and nanocomposites had different effect on the contents of nucleated cells materials (nucleotides, nucleosides, purine catabolites) in oral fluid, decreasing the contents of thymine, cytosine nucleotides and their derivatives, confirmed by absorption characteristics of oral fluid after the incubation. It was found that «Single Bond Universal» adhesive system, «Filtek Ultimate» and «Filtek Bulk Fill» nanocomposites also change the physical and chemical parameters of oral liquid and have a membrane-toxic effect on red blood cells. Conclusion. Biotesting of specified stomatologic materials showed that they are not completely bioinert.

stomatologic adhesives, nanocomposites, oral liquid