There are disclosed various embodiments of surgical tacks for use in surgical procedures. The tacks generally include a head and a barrel portion extending distally from the head. Preferably, the head and the barrel portion define a throughbore for receipt of a drive instrument. A thread on the head is provided to engage threads in the installation tool. A tissue thread is provided on the barrel portion to engage tissue. Distal and proximal surfaces of the tissue thread may be oriented at various angles relative to the barrel portion. There is also disclosed an insertion instrument to insert one or more tacks as well as a method of use. There is further disclosed a model device for use in explaining the operation of the instrument.