California Code
ARTICLE 9 - Dental Hygienists
Section 1959.

1959. A person who holds a valid, unrevoked, and unsuspended license as a registered dental hygienist, registered dental hygienist in alternative practice, or registered dental hygienist in extended functions under this article may append the letters “R.D.H.,” “R.D.H.A.P.,” or “R.D.H.E.F.,” respectively, to his or her name.

(Amended by Stats. 2011, Ch. 350, Sec. 13. (SB 943) Effective January 1, 2012.)