A Southwest Virginia dentist has pled not guilty to defrauding Medicaid by performing unnecessary dental work on children and the poor. Roy Silas Shelburne of Pennington Gap initially was charged in October in U.S. District Court in Abingdon with racketeering, fraud and money laundering. On Tuesday, a charge of structuring transactions in a way to avoid federal reporting requirements was added. The original indictment said Shelburne had been committing fraud since 1998 by either billing for unnecessary dental work he performed, doing one procedure but billing for another or by double billing for some procedures. U-S Attorney John Brownlee said some services performed by Shelburne were detrimental to the health of his patients. Shelburne remains free on bond. His federal trial is scheduled to begin October 22nd.