One or more chapters on dental hygiene is required in all textbooks on physiology used in the public schools of the state of Missouri. The chapters shall convey the proper knowledge to the pupil on the care, function and relation of the teeth to the general health. Such chapters in the textbooks shall be edited or approved by a competent committee composed of five members, three of whom are selected by the state dental society, one by the director of the department of social services, and one by the state board of education, and they shall serve without compensation. The sale or offer for sale of any textbook which does not contain the chapter on dental hygiene required by this section is a misdemeanor.