Probiotics are dietary supplements containing potentially beneficial bacteria or yeasts. They are administered in different quantities that allow for colon colonization. These products help in stimulating health promoting flora and also suppressing the pathologic colonization and disease spread. The use of probiotic plays an important aspect in dentistry too ever since the oral infections occupied the prime space among the other infections effecting the humans. This concept of microbial ecologic change both for medical and dental changes has accumulated a lot of evidence in recent times. But to date, no substantial literature and use has been postulated. There are claims that probiotics strengthen the immune system to combat allergies, stress, exposure to toxic substances and other diseases. There are reports of their beneficial use in HIV infection and cancers, mostly, the colo-rectal carcinomas. Their use in pre malignant and malignant oral disorders is yet to be probed. Strains of genera lactobacillus and bifidobacterium are the most widely used probiotic bacteria. This review is an attempt to discuss briefly the role of probiotics in medicine and dentistry.