Biomechanical finite element analysis of self-tapping implants with different dimensions inserted in two bone qualities.

Self-tapping dental implants offer the advantage of shortening the surgical insertion time of the implants and improve primary stability in poor bone quality. Using finite element analysis, a series of self-tapping implants with different diameters and lengths have been analysed with respect to their load transfer to the alveolar bone under axial and 45° loading conditions with a total force of 300 N. The implants were inserted in idealised bone beds with cortical thicknesses of 2 and 3 mm. The implants were considered to have osseointegrated condition. A linear decrease of the maximum stresses and strains in the bone around the implants was observed by increasing the diameter of the implants from 3.7 to 5.5 mm regardless of the length of these implants. Lateral loading of the implants caused a critical increase of the stresses and strains in the bone, in particular with the thin cortical layer of 2 mm. The determined biomechanical characteristics of the self-tapping implants showed their applicability in different bone qualities even with extreme reduced length of 7 mm.