Bone Formation of Titanium Implant Surfaces Treated with Submicron Poly(lactide-co-glycolide)/Recombinant Human Transforming Growth Factor- beta2 Particles by the Electrospray Method: An In Vivo Study.

PURPOSE: This study evaluated the effect of anodized titanium implants coated with submicron-sized poly(lactide-co-glycolide) (PLGA)/recombinant human transforming growth factor- beta2 (rhTGF- beta2) particles via electrospray on osseointegration in an in vivo model. MATERIALS AND METHODS: An experimental group of anodized titanium implants coated with submicron PLGA/rhTGF-beta2 particles by electrospray was compared topographically and histomorphometrically to noncoated anodized implants. Forty-eight anodized titanium implants were inserted into the tibias of 12 New Zealand rabbits. The histomorphometric specimens were prepared after sacrificing at 3 and 6 weeks after implant placement. Bone-to-implant contact percentage (BIC%) and bone area percentage (BA%) were calculated. The surface roughness and histomorphometric values were statistically analyzed, with a P value < .05 defined as statistically significant. RESULTS: The implant surfaces showed a uniform submicron-sized coating of PLGA/rhTGF-beta2 particles. There was no significant difference in surface roughness between the groups. Both BIC% and BA% of the three best consecutive threads in the experimental group (3 weeks postplacement) were significantly higher than those of the control group (P = .045 and P = .048, respectively), whereas only the BIC% of the three best consecutive threads of the experimental group (6 weeks postplacement) was higher than that of the control group (P = .033). None of the groups tested showed any statistically significant differences in these metrics along the total length of the implant. CONCLUSION: Within the limitations of this study, coating rhTGF-beta2 on implants with the help of PLGA carriers by electrospray may have enhanced osseointegration during the early stage of implant healing period in in-vivo rabbit tibia model.