Osseointegration of anodized titanium implants coated with fibroblast growth factor-fibronectin (FGF-FN) fusion protein.
OBJECTIVE
The synergistic effect of fibroblast growth factor (FGF) and human fibronectin fragment (hFNIII9-10) on osteoblast cell adhesion has been demonstrated in vitro. The purpose of this study was to evaluate the bone response around anodized titanium implants treated with FGF-FN fusion protein using the histomorphometric analysis and the removal torque test.


METHODS
Threaded implants were manufactured by machining a commercially pure titanium (grade 4). Two different groups of samples were prepared: Group 1 samples were anodized under a constant voltage of 300 V, and group 2 samples were anodized under a constant voltage of 300 V and then soaked in a solution containing fusion protein (65 microg/mL) for 24 hours. Ten implants from each group were placed in rabbit tibiae (1 implant per group per rabbit; each rabbit served as its own control). After a 3-month healing period, the animals were sacrificed. Removal torque testing and histomorphometric analysis was then carried out.


RESULTS
The mean removal torque value of group 2 (44.8 Ncm) was greater than that of group 1 (37.6 Ncm). The percentages of bone-implant contact of the best 3 consecutive threads were 76.37% for group 1 and 88.02% for group 2. The percentage of bone-implant contact for the total length of the implant was higher for group 2 (36.91%) than for group 1 (29.47%). However, the percentage of the area inside the threads that consisted of bone did not differ significantly for the 2 groups.


CONCLUSIONS
This study demonstrated that the FGF-FN fusion protein coating on anodized implants may enhance osseointegration. However, the influence of fibronectin- and FGF-treated rough surfaces on long-term prognosis and the propagation of inflammation are subjects for further study.
Park
Ji-Man
JM
Department of Prosthodontics & Dental Research Institute, College of Dentistry, Seoul National University, Seoul, South Korea.
Koak
Jai-Young
JY
Jang
Jun-Hyeog
JH
Han
Chong-Hyun
CH
Kim
Seong-Kyun
SK
Heo
Seong-Joo
SJ
D000818:Animals; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design; D005346:Fibroblast Growth Factors / Q000737:chemistry*; D005353:Fibronectins / Q000737:chemistry*; D006801:Humans; D016348:Osseointegration / Q000502:physiology*; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013977:Tibia / Q000502:physiology / Q000648:ultrastructure*; D014025:Titanium / Q000737:chemistry*; D019415:Torque; D014945:Wound Healing / Q000502:physiology
D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D003764:Dental Materials; D005353:Fibronectins; D011993:Recombinant Fusion Proteins; C501364:fibronectin type III like peptide, human; D005346:Fibroblast Growth Factors; D014025:Titanium