The human bone-oxidized titanium implant interface: A light microscopic, scanning electron microscopic, back-scatter scanning electron microscopic, and energy-dispersive x-ray study of clinically retrieved dental implants.
BACKGROUND
Surface modification of titanium implants by anodic oxidation may lead to enhanced bone integration. For instance, in vivo studies have demonstrated formation of more bone contacts in less time than for turned control implants. In addition, oxidized implants have shown a higher resistance to torque forces, indicating a strong interlock between bone and the oxide layer. However, the structure of the oxidized titanium-bone interface in high resolution is not known.


OBJECTIVE
The aim of the study was to analyze the human bone-oxidized titanium interface at a high-resolution level. Of particular interest was the relationship between bone tissue and the pores of the surface oxide.


METHODS
Twelve clinically retrieved implants with an oxidized surface (TiUnite, Nobel Biocare AB, Göteborg, Sweden) were used. Seven were regular dental implants and five were experimental mini-implants and had been subjected to immediate, early, or no loading. They were retrieved after 5 to 9 months of healing and were processed and analyzed using light microscopy, scanning electron microscopy (SEM) in normal and back-scatter (BS-SEM) modes, and energy-dispersive x-ray (EDX) analysis techniques.


RESULTS
Bone formation was observed to occur from adjacent bone structures toward the implant surface, and it was evident that bone formation had occurred at the implant surface. SEM, BS-SEM, and EDX revealed that mineralized bone had grown into the pores of the surface oxide layer, including pores with small diameters (< 2 microm).


CONCLUSIONS
The clinically retrieved oxidized implants showed evidence of bone growth into the pores of the surface oxide layer. The findings indicate the establishment of a strong interlock between the bone and the oxidized titanium implant, which is suggested to be beneficial for clinical performance.
Schüpbach
Peter
P
Peter Schüpbach Ltd, Laboratory for Microscopic Analysis, Horgen, Switzerland. pmsch@bluewin.ch
Glauser
Roland
R
Rocci
Antonio
A
Martignoni
Massimiliano
M
Sennerby
Lars
L
Lundgren
AnnaKarin
A
Gottlow
Jan
J
D020099:Coated Materials, Biocompatible; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D017267:Dental Prosthesis Design; D020878:Device Removal; D006801:Humans; D008853:Microscopy / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D016348:Osseointegration; D016062:Porosity; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties; D014025:Titanium
D020099:Coated Materials, Biocompatible; D015921:Dental Implants; C009495:titanium dioxide; D014025:Titanium