title: Osseointegration of two different phosphate ion-containing titanium oxide surfaces in rabbit cancellous bone.
abstract: OBJECTIVE
  This study assessed the osseointegration of grit-blasted titanium (Ti) implants with a hydrophilic phosphate ion-incorporated oxide surface in rabbit cancellous bone, and compared its bone healing with commercially available phosphate-incorporated clinical implants obtained by micro-arc oxidation (TiUnite, TU implant).
  
  
  METHODS
  The hydrophilic phosphate-incorporated Ti surface (P implant) was produced by hydrothermal treatment on grit-blasted moderately rough-surfaced clinical implant. The TU surface was used as a control. The surface characteristics were evaluated by field emission-scanning electron microscopy, X-ray photoelectron spectroscopy, optical profilometry, and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Thirty-two threaded implants with lengths of 10 and 3.3 mm diameter (16 P implants and 16 TU implants) were placed in the femoral condyles of 16 New Zealand White rabbits. Histomorphometric analysis, removal torque tests, and surface analysis of the torque-tested implants were performed 4 weeks after implantation.
  
  
  RESULTS
  The P and TU implants displayed micro-rough surface features with similar Ra values at the micron-scale. ICP-AES analysis revealed that both the P and TU implants released phosphate ions into the solution. The torque-tested P and TU implants exhibited a considerable quantity of bone attached to the surface. The P implants exhibited significantly higher bone-implant contact percentages, both in terms of the all threads region and the total lateral length of implants compared with the TU implants (P < 0.01), but no statistical difference was found for the removal torque values.
  
  
  CONCLUSIONS
  These results suggest that the phosphate-incorporated Ti oxide surface obtained by hydrothermal treatment achieves rapid osseointegration in cancellous bone by increasing the degree of bone-implant contact.
authors.affiliation: Department of Periodontology, School of Dentistry, Kyungpook National University, Daegu, Republic of Korea. jinwoo@knu.ac.kr
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Park
mesh_terms: D000818:Animals; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D020007:Implants, Experimental; D007477:Ions; D008297:Male; D008855:Microscopy, Electron, Scanning; D016348:Osseointegration / Q000502:physiology*; D010027:Osteotomy; D056951:Photoelectron Spectroscopy; D011817:Rabbits; D013054:Spectrophotometry, Atomic; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D019415:Torque
chemical_list: D015921:Dental Implants; D007477:Ions; C009495:titanium dioxide; C036532:titanium phosphate; D014025:Titanium