Down-coding is a process that insurance uses to attempt to dictate the type of treatment that is offered to patients. This is most typically utilized on dental procedures such as fillings and crowns. There are a number of different materials that can be used when filling a tooth or restoring a tooth with a crown.
Fillings can be done with the silver/mercury amalgam, dental composite (a type of plastic), ceramic or gold. The cheapest option is the amalgam restoration. Generally patients do not want the silver/mercury in their mouths and opt for the more esthetic composite (white) fillings that match their teeth better. There are a number of reasons why we don't use the silver fillings in our office , but the main one is that I believe the composite (white) fillings are currently better restorations, less prone to fracture and have better margins (where the filing and tooth meet). They also have little concern about safety, being that there is no mercury vapor released during mixture as there is with amalgam restorations. Even with all these concerns Dental Insurance companies many times will only pay their portion of amalgam restorations since they are much cheaper to place. Because they do this the patient is left to make up the difference in the cost of a composite filling and an amalgam filling.
For example: Lets say a composite filling costs $100 as negotiated by your insurance company. If the insurance coverage is 80% you would expect the insurance to cover $80 and you would be left with a copay of $20... easy enough to follow!
But, if your insurance down codes a composite filling to an amalgam filling we begin to have issues. If an amalgam filling is valued at $75 by your insurance company then they say they will only cover 80% of that amount or $60.