The Influence Of Three Type Of Toothpastes On Metal Element Released From Non-precious Dental Casting Alloys:an In Vitro Study

Objective The release of elements from dental casting alloys has been linked to alloy biocompatibility. This in vitro study was to measure elemental release from three types of commonly used dental non-precious casting alloys into toothpaste slurries of different functional toothpastes and artificial saliva after30minutes period brushing by Oral-B electric toothbrush or only immersed in the solution. Further to evaluate the Corrosion resistance of these alloys under the effect of different type of functional toothpastes. To provide a suggestion of the choice of functional toothpastes for the people who carrying dental non-precious casting alloys.Method75homemade wax pattern were prepared from silicone rubber, wax blocks were made by the method of wax dripping,75samples of three commercially available alloys (BevErox,Wirobond280BEGO,NEO TITAN) were casted in the form of13mm diameter discs,3mm in thickness by the method of lost wax casting, and were polished by a conventional technique. The number of each type of alloy was25, and was divided into five groups:Sensitive resistant toothpaste, Whitening toothpaste, Herbal toothpaste, ASB brushed without any toothpastes, and ASA only immersed in the artificial saliva without brushing as a control. There were five samples in each group. Each sample was placed into the solution and was brushed by Oral-B electrical toothbrush or only immersed for30min. In the end, Inductive Coupled Plasma Atomic Emission Spectrometry(ICP-MS) was used to determine the release of elements from the alloys into all collected medium. Statistical analysis were assessed with one-way ANOVA by SPSS17.0.Result1.More metal elements release were detected in ASB which brushed by an electrical toothbrush than in ASA which only immersed in Artificial Saliva for30minutes. More metal elements release were detected by ICP-MS in3functional toothpaste slurries than which in the two artificial saliva groups. Brush without toothpastes only leads to small amount of metal elements. The whitening toothpaste leads to the most metal elements release, following by sensitive resistant toothpaste, herbal toothpaste leads the least.2.Ni-Cr alloy releases the least amount of metal elements in ASA, ASB, Whitening toothpaste and Herbal toothpaste, following by Ni-Ti alloy, while Co-Cr alloy releases the least. But in Sensitive resistant toothpaste, Ni-Ti alloy releases the most, following by Ni-Cr alloy, Co-Cr alloy also releases the least.Conclusion1.Among three kinds of dental casting non-precious alloys, Co-Cr alloy shows the best corrosion resistance.2. The stress of brush increases the amount of the released metal elements. Brushed with functional toothpastes significantly reduce the corrosion resistance of all three kind of alloys, the Whiting toothpastes reduces the most, following by the Sensitive resistant toothpaste, Herbal toothpaste reduces the least.