Ultrasound surgical apparatus are disclosed, including: medical ultrasound handpieces with proximally mounted ultrasound radiators configured to create a distally-focused beam of ultrasound energy, in combination with distal guide members for control of focal point depth; medical ultrasound handpieces with proximally mounted ultrasound radiators configured to create a distally-focused beam of ultrasound energy, in combination with distal rolling members for manipulability and control of focal point depth; medical ultrasound handpiece assemblies with coupled end effectors providing a probe with a probe dilation region configured to have an average outside diameter that is equal to or greater than the average outside diameter of a probe tip and neck; as well as junctions to an ultrasonically inactive probe sheath; medical ultrasound handpiece assemblies with coupled end effectors having positionable, ultrasonically inactive probe sheath ends slidably operable to both cover and expose at least a probe tip; and ultrasound transducer cores including a transducing structure affixed to a longitudinally elongated, generally planar, single crystal or polycrystalline material waveguide.