Section 43A. The following words shall have the following meanings wherever used in this chapter or in any rules and regulations promulgated by the board in accordance with the provisions of chapter thirty A:—

''Aid or assist the dentist'', working simultaneously in conjoined manipulation with a dentist who is rendering treatment, as opposed to the performance of ''delegated procedures'' which does not require the immediate presence of a dentist.

''Appropriate supervision'', the type of supervision, whether direct or general, which the board specifies by rules and regulations as necessary for the performance of various procedures delegated by the board to dental hygienists or dental assistants.

''Delegated procedures'', those procedures performed under the direct supervision or the general supervision of a licensed dentist.

''Dental assistant'', a person registered by the board or authorized under section 511/2 and working under the supervision of a licensed dentist, whose purpose is to aid or assist a dentist in the delivery of patient care, or perform such delegated procedures under the supervision of a licensed dentist as determined by the board as may be authorized by rules and regulations of the board.

''Dental hygienist'', a person registered and licensed by the board, pursuant to the provisions of section 51.

''Direct supervision'', a dentist shall be physically present in a dental facility.

''Full time faculty member'', a dentist who devotes at least four full working days per week in teaching-patient care, research or administrative duties in the dental educational or research institution where he is employed.

''General supervision'', supervision of dental procedures based on instructions given by a licensed dentist but not requiring the physical presence of a supervising dentist during the performance of those procedures.

''Intramural group dental practice'', a dental practice comprised of full time faculty members under the auspices of the dental educational or research institution where they are employed.

''Placement of a restoration'', a procedure for the reconstruction of a tooth, or portion of a tooth, to its anatomical and functional integrity or the replacement of a tooth or teeth using those materials designed for the purpose which are accepted by the American Dental Association Council on Dental Materials and Devices.

''Public health dental hygienist'', a dental hygienist with at least 3 years of full-time clinical experience who is practicing full or part time in a public health setting pursuant to section 51 and who has received appropriate training as determined by the department of public health.