Biomechanical and histomorphometric evaluation of a thin ion beam bioceramic deposition on plateau root form implants: An experimental study in dogs

The aim of this study was to evaluate the biomechanical fixation, bone‐to‐implant contact, and bone morphology of an ion beam assisted deposition of a 300–500 nm thick Ca‐ and P‐based bioceramic surface on a previously alumina‐blasted/acid‐etched Ti‐6Al‐4V implant surface in a dog model. Materials and Methods: Thirty‐six 4.5 × 11 mm plateau root form implants, control (alumina‐blasted/acid‐etched‐AB/AE) and test groups (AB/AE+300–500 nm bioceramic coating, Nanotite™) were placed along a proximal tibia of six beagle dogs remaining for 2 and 4 weeks ( n = 3 animals per implantation time). Following euthanization, the implants were torqued to interface fracture at ∼0.196 radians/sec until a 10% maximum load drop was detected. The implants in bone were nondecalcified processed to ∼30 μm thickness slides for histomorphologic and bone‐to‐implant contact (BIC) assessment. Statistical analyses for torque to interface fracture were performed using a mixed model ANOVA, and BIC was evaluated by the χ2 test at 95% level of significance. Results: At 4 weeks, significantly higher torque to interface fracture was observed for the Test implant surface. Histomorphologic analysis showed higher degrees of bone organization for test implants compared to control at 2 and 4 weeks. Significantly higher BIC was observed at 4 weeks compared to 2 weeks (no statistical differences between control and test implants). Conclusion: The higher torque to interface fracture and increased bone maturity obtained in this study support that the surface modification comprising a 300–500 nm Ca‐ and P‐based bioceramic coating positively influenced healing around pleateau root form implants. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009