Fixed seat. The other end of the pneumatic control pipeline is connected to the chip blowing gas pipeline of the dental comprehensive treatment machine controlled by the chip blowing gas pedal button of the foot-controlled gas switch, and the fixed seat is respectively provided with a water valve, an air valve and a power switch. Oral instruments refer to all kinds of small portable tools specially used in stomatology, which are called oral instruments internationally. Oral instruments include dental mobile phones, oral mobile phone sterilizers, tooth extraction forceps, dental tappets, dental excavators and so on.