The board shall consist of five professional members and one public member appointed pursuant to section 38-158. Members shall meet the requirements of sections 38-164 and 38-165. The professional members shall consist of three licensed hearing instrument specialists, at least one of whom does not hold a license as an audiologist, one otolaryngologist, and one audiologist. At the expiration of the four-year terms of the members serving on December 1, 2008, successors shall be appointed for five-year terms.