Novel tightness-adjustable and noise-reducing dental handpiece

The invention discloses a novel tightness-adjustable and noise-reducing dental handpiece which comprises a handpiece head and a handle; the handpiece head comprises a shell and a clamping shaft, the two ends of the shell are detachably connected with a front cover assembly and a rear cover assembly, the clamping shaft penetrates through the front cover assembly, the front cover assembly and the rear cover assembly are each provided with a first threaded groove, the shell is provided with a second threaded groove, and the front cover assembly is fixedly connected with a water spraying assembly and an illumination assembly; a turbine mechanism is installed in the shell and comprises a turbine assembly and two bearings, clamping assemblies are fixedly connected to the outer side walls of the bearings, the clamping assemblies are in threaded connection with the first threaded groove and the second threaded groove correspondingly, a noise reduction assembly is fixedly connected to the turbine assembly, and a noise