Mass. Gen. Laws ch. 112, § 48

The board may, without examination upon payment of a fee determined annually by the commissioner of administration under the provision of section three B of chapter seven, register, and issue a certificate to, a dentist who has been lawfully in practice for at least five years in another state, if he presents to the board a certificate of registration, and duration of practice, from the board of dental examiners or other like board of said state; provided, that such other state shall require a degree of competency equal to that required of applicants in this commonwealth. Subject hereto, the board may waive written examination with respect to a dentist who has received a certificate of qualification from the National Board of Dental Examiners.