BACKGROUND/PURPOSE: Our previous study revealed that probiotic SD1 could reduce mutans streptococci as evaluated by cultivation-method as well as stimulate innate immunity. This study aimed to further investigate the effect of the probiotic on various oral bacteria by real-time PCR and salivary IgA levels.

MATERIALS AND METHODS

Forty children were included by randomization from either probiotic or control group in the previous study. The probiotic or control received milk-powder with or without . SD1, respectively once daily for 6 months. Saliva were collected at baseline 3-, 6-, and 12-months and were evaluated for total bacteria, total lactobacilli (TL), (LP/LC), total streptococci (TS) and using the real-time PCR. The salivary IgA (sIgA) was examined using the ELISA method.

RESULTS

All target bacterial levels were not significantly different at baseline in both groups. After milk-powder consumption, TL and LP/LC levels were significantly increased in the probiotic group, whereas TS and levels were significantly decreased compared to baseline. TS and levels were significantly lower, while the sIgA was greater in the probiotic compared to the control group. In the probiotic group, a positive correlation was found between LP/LC and sIgA, while negative correlations were observed between TS or levels and sIgA.

CONCLUSION

SD1 could control level and could stimulate sIgA. Results indicate that the SD1 strain may have a benefit for prevention of dental caries.