The administration of micro-organisms to improve the human health was already promoted by the Nobel prizewinning scientist Eli Metchnikoff in the beginning of the 20th century. However, it took several decades for this subject to become a topic of interest in medicine. At this moment these micro-organisms are called "probiotics" and defined as "living microorganisms which, when administered in adequate amounts, confer a health benefit for the host" (http://www.who.int/foodsafety/publications/fs_management/en/probiotics.pdf). Over the past decade probiotics have been extensively investigated from the perspective of oral health. It was shown that probiotics have the capacity to reduce mutans streptococci counts in saliva and/or plaque during their usage, that they have a positive influence on bad breath and that they can improve the results of scaling and root planing in periodontitis patients. A positive effect of probiotic usage on plaque accumulation and gingivitis measurements in gingivitis patients was also shown.To the investigators knowledge, at this moment no trials are available describing the effect of other probiotic genera on gingivitis. Since it is clear that probiotic effects are strain, dosage and mode of application dependent, the aim of this study was to evaluate the use of a probiotic toothpaste, mouthwash and toothbrush cleaner with Bacillus subtilis, Bacillus megaterium, and Bacillus pumulus versus a placebo in patients with generalized gingivitis.