The unusually shaped pair of cranium forceps were invented in the early 18th century by Samuel Sharp (1700 – 1788).
These were designed to grasp and lift out a disk of bone from the skull after trepanning.
Centrally under the brace there is another instrument for elevating a bone plate. A small loop screwed into the bone would to act as an anchor through which the arm of this instrument could apply leverage.
The two curved elevators (top right) would have been used to raise a bone flap. Once removed, the sharp blade of the lenticular (bottom right) was used to smooth the rough edges of the bone ends. The distal part of the blade ends in a circular button and this round smooth surface would protect the dura mater and the surface of the brain from damage.
The bone brush was used to clear away bone chips and shavings. The defect was nearly always closed and over the years there were a variety of materials used from metals (gold, silver and aluminium) to organic material, periosteal and skin flaps or bone homo, hetero and xeno-grafts.