There are conflicts of interest in dentistry (as with most medical practices) that arise in fee-for-service models of health care where the expert making a treatment recommendation is the same person who will be paid to provide the treatment. In other words, dentists are incentivized to find problems when they are paid for finding them.
Researchers from the Center for Advanced Hindsight looked at claims data from Delta Dental (the largest dental plan system in the United States) to understand whether different dentists were in agreement about identifying cavities from x-rays. The research also examined differences between claim costs from patients who had been to the same dentist for many years in comparison to new patients.
When two different dentists look at the same set of teeth, they are both likely to find issues, but there is only a 50 percent chance that the two dentists will come to the same clinical conclusion in terms of what the problem is and on which teeth. In addition, the longer someone has been seeing a dentist, the more they pay for the same treatment.