The science of a healthy smile

Our mouths are home to trillions of microbes, known as our oral microbiome

These microbes include a variety of bacteria, viruses, and fungi. Decades of research have shown that most are beneficial and keep us healthy, but others are harmful and cause diseases like cavities and gum disease.

We use genomics to measure the good and harmful bacteria in your saliva

Using a saliva sample, we analyze the DNA of every microbe to identify which species are present in your mouth and in what quantity. Higher levels of harmful bacteria indicate a high risk for disease.

We match your unique risk profile with our recommendations to help optimize your health

We've compiled research and consulted with a team of oral health experts to curate the most effective diet, lifestyle, hygiene, and oral care product recommendations for improving your overall health.


The good, the bad, and the ugly.

There are different types of bacteria in our mouth that play critical roles in keeping us healthy and functioning at our best— these are the "good" ones.

How do good bacteria help us?

Digesting food

Good bacteria help to break down proteins and sugars in the foods we eat.

Stimulating saliva

Spit is our body's natural healer and cleanser. It (1) washes away the food that bacteria feed on, (2) contains calcium, fluoride, and other minerals that help repair the protective surface of teeth through remineralization, and (3) covers our teeth acting as a barrier against bad bacteria.

Maintaining oral health

Examples of beneficial bacteria include Lactobacillus reuteri, Neisseria mucosa, and Streptococcus sanguinis. It's important to nurture good bacteria so they keep fighting the good fight, and keep our oral microbiome and smiles thriving!

Bad bacteria in our mouths convert sugar from the foods and drinks we consume into acid that erodes our teeth and the surrounding gums. An acidic environment in our mouth supports plaque buildup, a sticky coating on our teeth called biofilm. As plaque hardens on and around our teeth, it becomes tartar, weakening our teeth and gums.

What is the result of bad bacteria?

Tooth decay & cavities

The acids produced by these bad bacteria eat away at our enamel, leading to decay and cavities (tiny holes in our teeth).

Gum disease

Bad bacteria built up around our gum line convert into plaque and infect the surrounding tissue, causing bleeding, swelling, inflammation, and recession of our gums.

Bad breath

Bad bacteria produce odorous compounds called volatile sulfur compounds  (VSCs), which cause bad breath (halitosis).

The connection between our mouths and the rest of our bodies go far beyond chewing, swallowing, and digesting food. The bad bacteria in our oral cavity can travel throughout the rest of our body.

The downstream effects of poor oral health?

Damaged salivary glands

Oral health status can be a manifestation of systemic disease: an example is patients with Sjögren's syndrome experiencing destruction of salivary glands and reduced salivary flow.

Cardiovascular disease & diabetes

Oral disease can increase risk or signal the worsening of systemic disease: an example is individuals with periodontal disease having increased risk for cardiovascular disease and diabetes.

High levels of bacteria

Oral microbiome can signal the presence of systemic disease: an example is colorectal cancer patients having certain oral bacteria in distinctively abundant levels from individuals with cancer.

Spit happens.

What can we do about it?


By measuring the number of good and bad bacteria we have in our oral microbiome, we can gain insights into our unique microbiome and understand our oral health status.


Poor oral health can be the result of diet, poor hygiene, medications, and other lifestyle decisions. Once we understand our oral health we can create a plan to optimize it.


Not all oral health tips and products are effective at fighting off bad bacteria. With Bristle, you can measure your risk for disease over time and see what actually works.

Good health starts with ahealthy mouth

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