Fine grained osseointegrative coating improves biocompatibility of PEEK in heterotopic sheep model.
OBJECTIVE
Polyetheretherketone (PEEK) materials already have been used successfully in orthopedic and especially spine surgery. PEEK is radiolucent and comparable with bone regarding elasticity. However, PEEK is inert and the adhesion of PEEK implants to bone tissue proceeds slowly because of their relatively low biocompatibility. The aim of the study is to evaluate the effect of titanium and CaP coating on the adhesion of bone tissue.


METHODS
Six adult sheep (body weight 57.6 ± 3.9 kg) were included in this study. Three different types of cylindrical dowels (12 mm length x 8 mm diameter) were implanted in long bones (tibia and femur): PEEK dowels without coating (the control group), and PEEK dowels with a nanocoating of calcium phosphate (CaP group) or titanium (titanium group). Animals were sacrificed after 6, 12 and 26 weeks. Dowels were explanted for micro CT and histology.


RESULTS
Bone implant contact (BIC) ratio was significantly higher in the titanium versus control groups in the 6 to 12 weeks period (p = 0.03). The ratio between bone volume and tissue volume (BV/TV) was significantly higher in titanium versus control in the 6 to 12 weeks period (p = 0.02). A significant correlation between BIC and BV/TV was seen (r = 0.85, p < 0.05).


CONCLUSIONS
Coating of PEEK dowels with a nanocoating of titanium has beneficial effects on adhesion of bone tissue.
Medanex Clinic, Diest, Belgium.
Caroline M F
CM
Meers
Social Sciences Department, Ghent University, Ghent, Belgium.
Gino B M
GB
Verleye
IcoMetrix, Leuven, Belgium.
Dirk
D
Smeets
Medanex Clinic, Diest, Belgium.
Hadewych Y R
HY
Van Hauwermeiren
IcoMetrix, Leuven, Belgium.
Dirk
D
Loeckx
Department of Orthopaedic Surgery, AZ Delta, Roeselare, Belgium.
Karel
K
Willems
Orthobion GmbH Konstanz, Germany.
Vincent G M G G B
VG
Siau
Department of Morphology, Hasselt University, Diepenbeek, Belgium.
Philippe J M E
PJ
Lauweryns
Bone ingrowth; In vivo test; Nanotopography; Polyetheretherketone; spinal surgery; titanium