Table 2.

Studies examining tip-to-apex distance (TAD) and screw placement

Study	Recommended TAD	Position with ↑ cut-out	Optimum position
Hseuh et al. 2010	< 15 mm	Superior and inferior/posterior	Middle/middle or inferior/middle
Pervez et al. 2004	< 20 mm	Superior and anterior
Gundle et al. 1995		Superior and posterior
Baumgaertner 1995	< 25 mm	Superior and posterior
Parker 1992		Superior and posterior	Central and inferior
Davis et al. 1990		Posterior	Central
Mainds and Newman 1989		Superior	Central and inferior