I'll preface this by saying that yes there are unethical dentists out there and clearly this Lund guy is one of them and patients should never hesitate to get a second opinion if they feel uncertain.
However, this whole thing would be more informative and impressive if they had gone after the elephant in the room. Aspen Dental overtreats more than the rest of the dentists in USA put together. They are a "large health-care organization with substantial oversight... and standardized treatment regimens", but that oversight and standardization is geared entirely toward convincing every patient to get at least ten crowns. Aspen Dental are also large enough to hire lots of lawyers, so Atlantic isn't going to touch that with a ten-foot pole.