Dr Joyce Trail has been found guilty of conspiracy to defraud the NHS out of £1.4 million, in one of the biggest ever frauds in the history of the health service.
It's after she submitted up to 5,000 bogus patient invoices when working from a dental practice in Birmingham.
Her sister Fiona Trail and daughter Nyri Sterling were also standing trial at Birmingham Crown Court.
Nyri Sterling was found guilty for conspiracy to defraud. Fiona Trail was found not guilty.
The dentist and her sister were also found not guilty on charges of perverting the course of justice.