Evaluation of a predictive model for implant surface topography effects on early osseointegration in the rat tibia model.
BACKGROUND
Alterations in commercially pure titanium (cp Ti) implant surface topography can be made to increase bone formation or the interfacial shear strength of bone at the functioning implant. It is not known whether these 2 goals are congruent or mutually exclusive.


OBJECTIVE
The aim of this study was to determine the effect of implant surface topography parameters of calculated biomechanical significance on the process of bone formation in a rat tibia model of osseointegration.


METHODS
Implants (cp Ti grade IV) were machined and subsequently treated by grit blasting or grit blasting and 6.4 mol/L HCl. Measurements of surface roughness were made by atomic force microscopic analysis of similarly treated titanium disks. Cleaned and sterilized implants (12 machined, 12 with nonideal pit morphology, 12 with ideal pit morphology) were placed into the tibiae of 400-g male Wistar rats by using a series of drills, irrigation, and a self-tapping procedure. After 3 weeks, tibiae were harvested and processed and embedded in methyl methacrylate resin. Polished sections were examined by backscatter electron microscopy, and the percentage implant surface contacting bone was measured with the Scionics PC image analysis program. RESULTS. The implants possessing a proposed ideal pit morphology supported significantly greater bone formation at the implant surface (54% +/- 7% bone-to-implant contact [P<.003]) than the nonideal pit morphology (40% +/- 15%) or machined surfaces (34% +/- 6%).


CONCLUSIONS
Implant surfaces with a proposed ideal pit morphology (which possess a calculated biomechanical significance) enhanced bone formation at early periods after placement in the rat tibia model.
Abron
A
A
The Dental Research Center and School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Hopfensperger
M
M
Thompson
J
J
Cooper
L F
LF
D000818:Animals; D001696:Biomechanical Phenomena; D003775:Dental Polishing; D005544:Forecasting; D020007:Implants, Experimental; D008297:Male; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D016348:Osseointegration; D010012:Osteogenesis; D051381:Rats; D017208:Rats, Wistar; D013499:Surface Properties; D013977:Tibia; D014025:Titanium / Q000737:chemistry
D014025:Titanium