All board action on rules, regulations and policy matters, such as required to be by vote, shall be by roll call or mail ballot in which the vote of each member shall be recorded whether for, against or otherwise. The dental hygienist member of the board shall only vote on rules, regulations, policy and administrative matters relating to the licensing, qualifications and practice of dental hygiene. The results of the vote shall be a public record except that information pertaining to investigations or examinations shall be confidential unless waived by the persons investigated or examined.