In your letter of January 10,1940, you request us to furnish you with an answer to the following question:
Do the provisions of The Dental Law of April 30,1937, P. L. 554, 63 PS §121, require that each dental hygienist employed in the school districts of this Commonwealth shall be under the immediate supervision of some licensed or registered dentist practicing within the district, or are the provisions of this act met through the supervision provided by the Chief of the Dental Division in the Department of Health?
*158This inquiry arises by reason of the need of an interpretation of section 2 of the Act of 1937, supra, which is an amendment to The Dental Law of May 1, 1933, P. L. 216.
You have also informed us that for some time prior to the passage of this particular amendment, supervision of the vario.us “dental hygienists” employed by different school districts in this Commonwealth has been, and still is, exercised by the Chief of the Dental Division of the Health Department in Harrisburg, who is a licensed and registered dentist. You have also furnished us with the information that there are many school districts in this Commonwealth where there are no practicing dentists.
The provisions of the law referred to are a part of section 2 of the Act of April 30, 1937, P. L. 554, 63 PS §121, which reads as follows:
“A ‘Dental Hygienist’ is one who is legally licensed as such by the said dental council and examining board to remove tarter deposits, accretions, and stains from the exposed surfaces of the teeth and directly beneath the free margin of the gums, in the office of a dentist or any 'public or private institutions such as schools, hospitals, orphan asylums, and sanitoriums or State health cars, under the general supervision of a licensed and registered dentist, and not otherwise, and who does not perform any other operation or work on the teeth, jaws, gums or mouth whatever,” (Italics supplied.)
It has been urged by the Department of Public Instruction that unless the Chief of the Dental Division in the Health Department, located in Harrisburg, is permitted to provide that “general supervision” required by the provisions of the act, it means the breaking down of the dental hygienic program now in effect throughout our Commonwealth, inasmuch as many school districts have no practicing licensed and registered dentists, either because there is no dentist in the school district, or because the school district cannot afford to pay for the services of one.
*159The words “general supervision” at the most as used by the legislature in this statute are but a relative term. Neither the meaning of these words, nor any other provisions of the act, limit or require that the “licensed and registered dentist” be practicing in the same, or a near, school district where the dental hygienist is employed. While it may he argued that “general supervision” by a registered and licensed dentist of the same, or a near, school district would be more preferable than the “general supervision” exercised by the Chief of the Dental Division in the Department of Health, yet it is clear that the legislature did not see fit to adopt this point of view. We may not, therefore, read more into the law than was intended by the legislature.
“It is a fundamental rule of statutory construction that courts in seeking for the legislative intent must find it in the statute itself; that unless good grounds can be found in the statute for restraining or enlarging the meaning of its words, the court cannot subtract therefrom or add thereto. Where the words of a statute are plain and clearly define its scope and limit, construction cannot extend it”: Grayson v. Aiman, Inc., 252 Pa. 461.
It appears, theref.ore, that the answer to your question is that a dental hygienist may practice under the “general supervision” of a licensed and registered dentist regardless of whether the dentist is practicing in the same school district or is located in some other near-by school district within this Commonwealth.
It is our opinion, and you are therefore advised, that a dental hygienist may perform the operation and work permitted by the law for a school district as long as these services are performed under the “general supervision” of a licensed and registered dentist, who need not be a practicing dentist in the same, or a near-by school district. This “general supervision” may be exercised by the Chief of the Dental Division in the Department of Health, as long as he is a licensed and registered dentist in this Commonwealth.