Fatigue life of bioactive titanium dental implants treated by means of grit-blasting and thermo-chemical treatment.
OBJECTIVE
This study focuses on the fatigue behavior of titanium dental implants as-received, with a grit-blasted surface and with a new bioactive surface treatment (2Steps).


BACKGROUND
The 2Step process consists of (1) an initial grit-blasting process to produce a micro-rough surface, followed by (2) a combined thermo-chemical treatment that produces a potentially bioactive surface, that is, that can form an apatitic layer when exposed to biomimetic conditions in vitro. The 2Step treatment produced micro-rough and apatitic coating implants.


METHODS
Residual stresses were determined by means of X-ray diffraction. The fatigue tests were carried out at 37°C on 500 dental implants, and the S-N curve was determined. The fatigue-crack nucleation for the different treatments was analyzed.


RESULTS
The fatigue tests show that the grit-blasting process improves the fatigue life. This is a consequence of the layer of compressive residual stresses that the treatment generates in titanium surfaces. Dental implants that had its surfaced prepared with the 2Step procedure (grit-blasting and thermo-chemical treatment) had its fatigue life decreased by 10% due to the incorporation of oxygen to the surface and the relaxation of the compressive residual stress produced by the heat treatment.


CONCLUSIONS
Thermo-chemical treatment is an excellent compromise between the improvement of bioactive and mechanical long-life behaviors.
Bioengineering Research Center (CREB), Department of Materials Science and Metalurgical Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain; Facultad de Odontología, Universidad de Sevilla, Sevilla, Spain.
F Javier
FJ
Gil
Eduardo
E
Espinar
Jose Maria
JM
Llamas
Pablo
P
Sevilla
D001672:Biocompatible Materials; D015921:Dental Implants; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D014025:Titanium; D014961:X-Ray Diffraction
D001672:Biocompatible Materials; D015921:Dental Implants; D014025:Titanium
bioactivity; dental implants; fatigue; titanium