Four PC replacement resins (Tritan™ and PS) released chemicals having EA.
We emphasize that the results for the EA-free replacement resins reported herein do not imply that products made from such resins will always be EA-free, but rather they can be EA-free if the apprropriate additives and manufacturing processes are used.
[Only one resin, PS, was a PC-replacement resin].
However, none of these previous studies identified the possible origin for the release of chemicals having EA at the most basic level, i.e., the BPA-replacement resin itself or chemicals added to the BPA-free resin during the processes used to manufacture the finished product.
There are no studies of which we are aware examining the EA of extracts of any BPA-free PC-replacement resin (or product) using an in vivo assay (i.e. measurement of the ability of an extract to stimulate uterine growth or ER-dependent gene expression).
Also, tooth replacements were recorded, including type of replacements (resin bonded FDP, conventional FDP, partial RDP and complete dentures) and location in the dental arch.
However, ten other PC-replacement resins did not leach chemicals having EA (EA-free-resins).
All products transmitted UV radiation over a range of wavelengths typical for each respective class of PC-replacement resins.
However, aging or stress per se did not always increase release of chemicals having EA from PC-replacement resins.
We noted no consistent cost differential between PC-replacement resins having or lacking EA assayed in this paper, or for PC-replacement products made from such resins analyzed in our previous paper [ 17].
Figure 2 presents data obtained at CCi for the total EA (%RME2) of chemicals extracted from eleven BPA-free PC-replacement resins, stressed or unstressed, sorted first by type of assay, type of extract, and type of stress.
