In terms of hygiene and environmental protection: According to epidemiological data, there is a serious problem of cross-infection in oral diagnosis and treatment in China. Hepatitis B infection rate of dentists is 3-6 times higher than that of the general public, the HBV positive rate of dentists is 25.8%, and the total positive rate of HBV contamination of dental handpieces is 62%. Therefore, preventing cross-infection of dental equipment is an important factor to be considered in the design of dental chairs. Handpiece is the most basic and important configuration of dental chair equipment. At present, the domestic use of high-speed imported turbine handpiece brand NSK, DN, Bien Air and W&H, etc., the speed up to 350,000r/min (0.25Mpa when), generally can withstand conventional 120 ℃ and rapid 135 ℃ high temperature, high pressure sterilization. Needle loading and unloading methods are divided into wrenches to change the needle and press the button to change the needle of two kinds; the interface is divided into international standard two-hole, four-hole type. The low-speed handpiece is generally divided into two kinds of straight and elbow, and the pneumatic motor for 1:1 equal speed rotation. When the handpiece stops rotating, due to inertia, it will produce a suction back airflow, resulting in broken chippings and pollutants inhaled into the handpiece, which is an important way of cross-infection in oral health care. Therefore, the anti-suckback handpiece device has become an important configuration of high-grade products. At present, the anti-suckback handpiece in high-grade chairs mainly adopts the patented technology of Japan and Germany. In the middle and high-grade products are equipped with replaceable discrete water supply, disinfection and timed rinsing of the automatic health system, in the PU elastomer frame, paint using nano-antibacterial technology, mouthwash pelvis, oral lamp and lamp shade also has antibacterial health care functions.