By the time you reach adulthood, roughly 100 trillion microscopic organisms will have taken up residence in and on your body, outnumbering your own cells 10 to 1. Most are bacteria, a domain of the animal kingdom considered synonymous with disease. But only a few of the thousands of bacterial species cause us harm; the rest are either benign or actually beneficial to our health, including in our mouths.
Dentistry pioneered much of our knowledge about bacteria, developing processes used to identify, classify and understand those species inhabiting our mouths. Science as a whole is catching up with the Human Microbiome Project (HMP) begun in 2007. Through HMP, researchers have catalogued and begun to study more than 10,000 bacterial species.
We’re finding that our bodies develop a symbiotic relationship with many of these creatures invisible to the naked eye. During our infancy the bacteria we ingest from birth and breast feeding begin to interact with our body’s immune system, “teaching” it to refrain from attacking friendly organisms that contribute to health and searching and destroying enemy species that cause disease.
We’re also learning that an imbalance with our individual population of bacteria has links with disease. Our digestive system is a prime example: bacteria related to obesity can overpopulate our digestive tract, while malnutrition can create an environment that produces too many bacteria that inhibit digestion of vitamins and other nutrients.
The same microbial imbalance can occur in the mouth. For example, our typical Western diet encourages the growth of bacteria most associated with tooth decay (Streptococcus mutans). We’re also finding that tobacco smoking creates a mouth environment more conducive to the bacteria that cause gum disease. Just by quitting smoking you can alter that environment to encourage growth of health-promoting bacteria and inhibit growth of malevolent species.
The desired outcome of this knowledge is to develop treatments that target disease-causing bacteria without harming those beneficial to us (as often occurs with traditional antibiotics). In dentistry, such possibilities could help stop the spread of tooth decay, gum disease or similar bacterial infections, while fostering a healthier oral environment that prevents disease and protects health.