The title “Doctor”, “Doctor of Chiropractic” or its abbreviation “D.C.” shall not be used unless the chiropractic physician is the holder of an earned degree of Doctor of Chiropractic from an educational institution duly recognized by the Board, and the designation of “Chiropractic Physician,” “Doctor of Chiropractic,” or “Chiropractor” must appear immediately after the name. The name and designation “D.C.” may be used by the holder of an earned degree recognized by the Board.