A licensed speech-language pathologist or audiologist who holds a doctoral degree in speech-language pathology or audiology or a related field may use the title “Doctor” or “Dr.” on written materials only if the earned doctoral designation abbreviation accompanies the licensee's name. A licensee who is not also licensed to practice medicine or osteopathy in this Commonwealth may not attach to his name or use as a title the words or abbreviations “Doctor” or “Dr.” in contravention of this section, “M.D.,” “physician,” “surgeon,” “D.O.” or any word or abbreviation that suggests that the licensee practices medicine or osteopathy.