**9. Probiotics and periodontal disease**

Periodontal diseases include gingivitis and periodontitis. They are manifested by bleeding on probing, swelling, color alterations, pain, and tooth mobility in

advanced stages. Scaling and root planning and deep pocket debridement are usual treatments [10]. Periodontal pathogens could be regulated by means of antagonistic interactions. According to the results of studies probiotics have been shown to reduce the number of the most frequently isolated pathogens such as *Bacteroides* sp., *Actinomyces* sp., *Staphylococcus intermedius*, and *Candida albicans* at optimal concentrations of 108 cfu/ml [23].
