Police say Kestler was doing his drilling and filling out of a car.
The Santa Fe New Mexican reports that Kestler, also known as Eliver Lopez, was arrested Saturday following a tip from a former customer.
According to police, investigators discovered Kestler with a portable drill machine and other dental equipment in a small, red Chevrolet sedan.
Authorities say Kestler told police that he had a dentistry license in Mexico but not in the U.S.
Kestler, who was wearing blue hospital scrubs when he met with police, was arrested on a number of charges, including practicing dentistry without a license.
It was unclear if he had an attorney (not to mention a hygenist).