Disclosed is a composition and method for the treatment and prevention of bad breath, halitosis, gingivitis, and / or periodontitis that contains one or more varieties of probiotic bacteria from the groups Lactobacillus, Bacillus, Escherichia, Enterococcus, Streptococcus, and Bifidobacterium, and / or a species of the yeast genus Saccharomyces. The composition may be in a variety of forms, such as a toothpaste, mouthwash, oral spray, oral cream or gel, chewing gum, candy, lozenges, dissolvable pill or strip, or powder that may be sprinkled directly into the oral cavity.