For oil companies with difficult-to-drill assets, here is some good news. PDTI Holdings (dba Particle Drilling Technologies) is developing an advanced drilling technology it hopes will provide a dramatic increase in penetration rates for drilling oil and gas wells. Its Particle Impact Drilling System advanced drilling technology is designed to drill through deep, hard, and abrasive zones or other difficult-to-drill geologic formations. The Particle Impact Drilling System uses a custom-built drill bit fitted with jetting nozzles and polycrystalline diamond compact cutting structures. Never able to make the technology profitable, the company filed for and emerged from Chapter 11 bankruptcy protection in 2009.