Adsorption from black tea and red wine onto in vitro salivary pellicles studied by ellipsometry

Abstract

The adsorption of black tea and red wine components onto a pellicle-like protein layer formed in vitro by adsorption from whole unstimulated saliva on hydroxyapatite discs were studied by in situ ellipsometry. It was found that components from black tea readily adsorbed to the pellicle. Subsequent exposure to saliva led to further adsorption of salivary components to give an overall increase in the amounts adsorbed. The amounts adsorbed increased still further following a third tea and saliva exposure. Components of red wine gave significantly greater amounts of adsorption to the pellicle than black tea. The adsorption of components of black tea gave a concomitant increase in colour or stain as measured by a reflectance chromameter. In all cases, the black tea- and red wine-modified pellicles were not eluted by either phosphate buffer or sodium dodecyl sulphate (SDS) rinses. Thus, black tea and red wine components have been shown to have a profound effect on in vitro pellicle maturation, causing thickened layers of stained material to build up, which are not readily removed.

Risk Factors Associated with Black Tooth Stain

“…Statistically signifi cant diff erence was only found for red wine intake. Patients with tooth discolorations consumed less red wine than patients without discolorations, which is contrary to the previously mentioned studies reporting that highly pigmented beverages such as black tea and red wine cause extrinsic tooth discoloration [23][24][25] . Our fi ndings might be explained by the fact that wine stays in the oral cavity shorter than vegetables and therefore there is less opportunity for pigment formation 10 .…”

“…Other similar investigations pointed out that highly pigmented, acidic beverages not only caused tooth discoloration but also dissolution of the enamel [27][28][29][30] . Joiner et al also showed that black tea and red wine components had a profound eff ect on in vitro pellicle maturation while causing thickened layers of stained material to build up 23 . Extrinsic tooth staining can be caused by compounds that are incorporated into the pellicle and produce a stain consequently to their basic color (chromogen), or those that lead to staining caused by chemical interaction at the tooth surface, which is usually associated with cationic antiseptics and metal salts.…”

“…Costa et al 44 and Li et al 40 report on a similar prevalence of S. mutans in dental biofi lms of patients with and without black stain. Th e presence of black stain has been reported to be associated with a low frequency of caries, but the reasons are still unknown 23 . Finally, all the above studies indicate a unique microbiological composition of dental plaque with black stain; however, with only a few selected species evaluated, the relationship between microorganisms and black stain still remains uncertain and incomplete.…”

“…It is interesting to notice that Coca-Cola, red juices, coff ee and tea in this experiment did not show any signifi cant diff erence. However, most of the studies assume these drinks as the main factors in tooth discoloration development 26,23 . Other similar investigations pointed out that highly pigmented, acidic beverages not only caused tooth discoloration but also dissolution of the enamel [27][28][29][30] .…”

The relevance of alcohol to dental practice

“…It is thought that dietary chromogens in the drink are adsorbed to the pellicle, leading to a layer of stained material, which is not easily removed. 28 It has been shown that post bleaching, the susceptibility of enamel to red wine staining increases and post bleaching red wine causes greater staining than coffee. 29,30 Red wine also stains composite more than tea or coffee.…”