Okla. Stat. tit. 59, § 59-887.14
Titles and abbreviations
Any person holding a license pursuant to the provisions of the
Physical Therapy Practice Act as a physical therapist may use the
title "Physical Therapist", "Registered Physical Therapist", or
"Licensed Physical Therapist", or the letters "P.T.", "R.P.T.", or
"L.P.T.", as authorized by the license obtained from the State Board
of Medical Licensure and Supervision. Any person holding a license
pursuant to the provisions of the Physical Therapy Practice Act as a
physical therapist who has earned a Doctor of Physical Therapy
degree from a program approved by a national accrediting body
recognized by the Board may use the title "Doctor of Physical
Therapy" or the letters "D.P.T.".