The fastener is also easily removed, for example, by inserting an instrument into recess 64 of cap 60 and rotating the cap off of the fastener, to allow the bone flap to be subsequently removed if a follow-up neurosurgical procedure is required. [0068] The fastener 10 is made of any biocompatible material, including stainless steel, titanium alloy, polyglycolic acid, silicone rubber, teflon or nyl