The effects of saliva on the erosive potential of three different wines

The erosive potential of wine on teeth may be modified by the buffering capacity of saliva. This potential effect was studied for three different wines in vitro and in vivo.

The buffering capacity was studied in vitro by stepwise addition of small volumes of a dry white wine, a medium sweet white wine and a red wine to collected stimulated saliva. In vivo, this was studied by six volunteers vigorously rinsing 5 mL of each wine in their mouth for 15 to 45 seconds. Changes in salivary flow rate and pH were measured during a period of 10 minutes after rinsing with 5 mL wine.

pH values < 5.5 were observed in vitro after addition of 0.2 mL dry white wine and medium sweet wine and after 0.3 mL red wine to 1 mL saliva. During rinsing with all wines, the intra-oral pH decreased to below 4 within 15 seconds and remained below this value for at least 45 seconds. After expectoration, the salivary pH remained significantly low for two to six minutes, despite a doubling of the flow rate observed during the first two minutes.

Vigorously rinsing wine induced a decrease in intra-oral pH of significant degree and duration, which increases the risk of developing dental erosion.