GB/T 9937 specifies oral terms. This part is about terminology related to oral appliances. The basic and clinical terms of oral cavity, dental instruments and dental equipment, and the terms of tests related to these products are included in the other 4 parts of GB/T 9937. The purpose of this part is to provide some recognized oral terms and definitions for the formulation and implementation of standards, so as to facilitate the understanding of the document, and to promote mutual exchange.