On a 1,000 point scale, UnitedHealthcare's vision plan scored 729, ahead of second-place EyePlan, which scored 712. The company's dental plans scored 754, followed by DentaQuest, which scored 736. It was the second year in a row that the carrier's dental plans received first place in the J.D. Power survey.

In a statement, the company attributed its high marks from customers to its investments in new mobile technology that helps members locate nearby providers on their smart phones. Philip Kaufman, president of the company's specialty benefits division, framed the ranking as evidence that the company's enormous size did not prevent it from tailoring its benefits to match needs specific to certain areas.

“Every employer and community we serve has unique health care needs, so that requires a commitment from our entire organization to deliver superior service,” he said. “UnitedHealthcare's local-market focus and national resources enable us to meet the oral and visual health needs and enhance the well-being of the more than 20 million people enrolled in our vision and dental plans.”

The J.D. Power reports displayed a greater divide between dental plans than vision plans, largely because most vision plans were grouped together at lower scores, on average. The lowest performing vision carrier was Davis Vision, which scored 698. Cigna, the lowest-scoring health carrier according to the ASCI, also had the worst-ranked dental plan according to J.D Power, coming in at 701.

The report showed that most customers do not feel particularly loyal to their dental or vision carrier, with only 40% of vision beneficiaries saying they will definitely pick their current insurer in the future and only 43% of dental plan members saying they were committed to their current carrier.