Aim: To provide scientific background from animal model for implant application in patients under immunosuppression.

Materials and methods: Forty eight Wistar male rats in six groups were receiving: (1) ( n = 12): Cyclosporine A (CsA) + Mycophenolic acid (MPA) + Glikocorticosteroids (GS), (2) ( n = 12): Tacrolimus (Fk-506) + Mycophenolic acid (MPA) + Glikocorticosteroids (GS), (3) ( n = 6): Cyclosporine A (CsA) + Rapamycin (RAPA) + Glikocorticosteroids (GS), (4) ( n = 6): Tacrolimus (Fk-506) + Rapamycin (RAPA) + Glikocorticosteroids (GS), (5) ( n = 6): Rapamycin (RAPA) + Mycophenolic acid (MPA) + Glikocorticosteroids (GS), (6) ( n = 6) no treatment. After three months, titanium miniscrews were placed in their tibias. Then, subgroups ( n = 6) from two first groups were converted to Rapamycin. Three months later the animals were sacrificed and their left tibias and femoral bones were used to measure bone bending strength and range as well as strength of osteointegration. The values received were compared using Kruskal–Wallis and Mann–Whitney tests ( p < 0.05).

Results: Screw removal strength was from 27 N for CsA/MPA/GS converted to RAPA to 43.9 N for CsA/MPA/GS, however no statistically significant differences were found between study and control groups. Femoral bone breaking force was from 160.18 N for Fk-506/RAPA/GS to 884.65 N for CsA/MPA/GS, significantly lower in the treated comparing to control groups, except for the group taking CsA/MPA/GS, where it was higher. The range of bone bending was reduced in all groups treated comparing to control.

Conclusion: Despite a reduced bone bending strength, implant osteointegration was not compromised by immunosuppression.

Conflict of interest: None declared.