Initially, micro-dissection needle tips were all made out of stainless steel. The manufacturing process for stainless steel surgical needles has been known for centuries. The needle tip geometry is achieved by running multiple passes on point grinding machines. (See: Taper point grinding machine)
Due to the grinding process of the stainless steel needle tip, sharpness can be inconsistent. Stainless steel material has a fairly low melting point (1,400 – 1,500° C). The heat generated at the tip during surgery quickly dulls the sharp point, making the instrument unusable.
In contrast, tungsten material has a very high melting point of 3,422° C, keeping the micro-dissection needle point sharp even after extensive use.
The high melting point of tungsten combined with an ultra-sharp tip allows the instrument to not only be more durable but reduces the electric power required for surgery.
Plus, the highly polished tip prevents sticking and wipes easily.
The radius of tungsten tips is produced within a very small tolerance range (+/- 0.5 my), impossible with stainless steel. This allows needle types to be changed during surgery without the need to adjust power settings of the RF generator.