The Influence of Black Tea on Secretory IgA from Saliva in Caries and Caries-Free Subjects

Abstract

The crucial role of saliva in the prevention of dental caries is associated with the regulation of its flow rate as well as salivary protein. Black tea, derived from the plant Camellia sinensis, contains catechins and has been shown to have a beneficial effect on saliva in preventing tooth decay. Nevertheless, research on the oral health benefits of black tea is still limited. This study aimed to investigate the effects of black tea (Camellia sinensis) on salivary pH (potential hydrogen), salivary flow rate, lysozyme, and sIgA levels in caries and caries-free patients. The study used a quasi-experimental design with a pre-test and a post-test. Twenty six subjects (male or female) were selected and divided into two groups (caries and caries free), thirteen subjects for each. Saliva samples were obtained before and thirty minutes after tea consumption. The flow rate of saliva was measured by dividing the weight of saliva collected by the time. At the same time, secretory immunoglobulin A (sIgA) levels were analyzed by enzyme-linked immunosorbent assay (ELISA). The t-dependent and t-independent tests and Mann-Whitney tests were selected to evaluate the effect of drinking black tea on salivary flow rate and sIgA value. The results showed that black tea significantly increased salivary flow rate but did not significantly affect the concentration of sIgA. No statistically significant differences in salivary flow rate and sIgA were observed between patients with and without caries after tea consumption. Although the concentration of sIgA did not demonstrate a significant change, however, the salivary flow rate was significantly enhanced. Therefore, drinking black tea did not negatively affect the saliva in the oral cavity, suggesting it can be a good option for daily consumption due to its protective role against dental caries.