He spent twenty years filming the inside of people's mouths through a microscope. Then he handed them the camera.
Craig S. Kohler, DDS, MBA, MAGD. He kept the same office for forty years and expanded it five times - restless in place.
Craig Kohler runs ONVI, and ONVI is trying to do something odd: make you look before you brush. Most of oral care happens blind. You scrub for two minutes over a sink, guessing. Kohler's company builds tools that turn on the lights - literally, in the case of an LED brush called MOTSY Light, and literally again in the case of Prophix, a toothbrush with a camera in the head that streams a live feed of your gumline to your phone.
In August 2025 ONVI announced a $25 million Series A to commercialize the whole family at once: the connected Prophix brush, the LED manual line, and ONView - a HIPAA-compliant platform meant to carry that data from the bathroom to the dental office. The framing Kohler uses is deliberately un-dental. He does not talk about plaque. He talks about visibility, behavior, and data. "At ONVI," he says, "we believe better health starts with better visibility."
It is a big claim from a small operation - the kind of company where the founder is also the inventor listed on the patents. But the claim has a decade of stubborn engineering behind it. ONVI counts 39 issued patents and roughly $4 million of private R&D poured in before a single product went wide. Kohler did not arrive at the connected toothbrush through a whiteboard brainstorm. He arrived through a chair, a microscope, and a couple of thousand patients.
As I used intraoral cameras and monitors to treat my patients, I saw how it helped them better understand their oral health - and in turn, adopt better cleaning habits.
Craig Kohler, on the observation that became a companyIllustrative - based on Kohler's stated clinical experience, not a published study.
Kohler is among a small group of American dentists who, for more than twenty years, ran live video and surgical microscopes during procedures. Extreme magnification is a specialist's habit - it lets you catch a problem while it is still small enough to fix cheaply. He got good enough at it to train more than 500 other dentists in what the field calls micro aesthetic dentistry, and to speak about it on stages here and abroad.
Somewhere in those thousands of appointments he noticed the thing that would not leave him alone. When a patient could actually see the inside of their own mouth on a monitor, they brushed better afterward. Not because he lectured them. Because they had looked. The screen did the persuading.
That is a small observation with a large door behind it. If seeing changes behavior, and behavior is most of oral health, then the highest-leverage move is not a better bristle - it is a better view. In 2013 he founded ONVI to drag that clinical monitor out of the office and into the home.
The early Prophix prototypes were 3D printed. A reporter who handled one at a trade show guessed selective laser sintering and admired the finish. It took another decade of patents and private capital before the vision looked like a lineup instead of a curiosity.
An LED-illuminated modular toothbrush. The lights turn the mirror into a diagnostic surface.
Enhanced-visibility variant - Kohler's first consumer invention to leave the practice.
An ergonomic one-handed flossing tool built for the parts you never quite reach.
Rechargeable model with airflow defogging - because a fogged lens sees nothing.
Smartphone-connected brush with embedded video. Watch the spots you miss, live.
A clinical-grade diagnostic platform version for the practitioner's side of the chair.
The connective tissue: a HIPAA-compliant SaaS layer for teledentistry, behavior tracking, and payer integration. The hardware collects the picture. ONView is where the picture becomes a record - the piece that makes "operating system for oral health" more than a slogan.
Opens a dental practice on Chicago's North Shore in Wilmette. He will expand the same office five separate times over the years - growth without ever moving.
Adopts surgical microscopes and live intraoral video, joining a small national cohort recording procedures at high magnification.
Founds ONVI to bring the clinical monitor home. The thesis: people change habits when they can see.
ONVI debuts Prophix, billed as the first-ever smart video toothbrush that streams to a mobile app.
Shows Prophix at CES in Las Vegas - years before teledentistry became a mainstream phrase.
Invents MOTSY Light, the LED manual system, and builds out the ONView data platform.
Launches a $25M Series A to commercialize the full stack - hardware, powered brushes, and software - at once.
With today's advancements in technology, it is finally possible to bring this never-before-seen dental solution into the home.
Craig Kohler, at the launch of ProphixHis toothbrush is also a camera. It streams live footage from inside your mouth to an app.
He earned a Mastership in the Academy of General Dentistry - 1,600+ hours of advanced training.
Same office for 40 years, expanded five times. Ambition can be a homebody.
The first prototypes came off a 3D printer - a founder building his own future by hand.
The dental business model has an awkward truth at its center: it makes most of its money when things go wrong. Cavities, crowns, root canals, extractions - the invasive end of the trade. Kohler's whole wager runs the other way. If people can see problems early, at home, most of the expensive drama never happens.
That is why ONView matters more than any single brush. A camera in a toothbrush is a gadget. A camera feeding a HIPAA-compliant record that a hygienist can review, that a payer can price, that tracks whether your habits are trending better or worse - that is infrastructure. Kohler is not really selling toothbrushes. He is selling a feedback loop and betting the health system eventually pays for the version that keeps you out of the chair.
It is an unglamorous, patient bet from someone who has been patient for forty years. Whether the market rewards prevention as generously as it rewards repair is the open question ONVI's Series A is designed to answer.