Dental insurance continues to be the king of the voluntary benefits hill.

The Wellesley, Mass., employee benefits group at Sun Life Financial Inc., Toronto (NYSE:SLF), has published that finding in a summary of results from a recent online survey of 2,800 U.S. employees working full-time or part-time for employers with at least 25 workers.

About 86% of the participants cited dental insurance as a highly valued voluntary worksite benefit.

The percentage of participants who place a high value on a benefit was 77% for vision benefits and 401(k) plans, 62% for life insurance, 60% for long-term disability insurance, 56% for short-term disability insurance and 46% for long term care insurance.

Asked about how they prefer to get information about employers’ benefits, 84% said they like printed materials and 68% said they like getting information online. Just 24% said they like getting benefits information through toll-free telephone numbers.

Sun Life also found a possible decrease in the percentage of employers paying the full cost of certain benefits.

Only 13% of survey participants said their employers were paying the full cost of vision benefits, down from 18% in 2009, and only 13% said employers were paying the full cost of medical insurance, down from 17%.