Fused silica shows three distinct regimes during nanoindentation, i.e. plastic deformation, inelastic densification and cracking. Cohesive zone FEM is used to study these regimes for different indenter geometries. In a three dimensional model, the median/radial cracking is considered by introducing cohesive element planes. In addition to comparing indentation cracking data with experimental data, the role of densification on indentation crack growth is critically examined using a pressure independent Von Mises and a pressure dependent Drucker-Prager-Cap constitutive model. The results show that the Drucker-Prager-Cap model delivers an accurate description of the elastic-plastic deformation conditions for all examined indenter geometries. Material densification leads to shorter crack lengths and thus larger fracture toughness values. Once the crack was initiated its propagation is comparable for blunt indenter geometries (Berkovich), while densification leads to a slower crack propagation for sharper indenter geometries.